/* * Copyright (C) 2013 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef ANDROID_INCLUDE_CAMERA3_H #define ANDROID_INCLUDE_CAMERA3_H #include #include "camera_common.h" /** * Camera device HAL 3.4 [ CAMERA_DEVICE_API_VERSION_3_4 ] * * This is the current recommended version of the camera device HAL. * * Supports the android.hardware.Camera API, and as of v3.2, the * android.hardware.camera2 API as LIMITED or above hardware level. * * Camera devices that support this version of the HAL must return * CAMERA_DEVICE_API_VERSION_3_4 in camera_device_t.common.version and in * camera_info_t.device_version (from camera_module_t.get_camera_info). * * CAMERA_DEVICE_API_VERSION_3_3 and above: * Camera modules that may contain version 3.3 or above devices must * implement at least version 2.2 of the camera module interface (as defined * by camera_module_t.common.module_api_version). * * CAMERA_DEVICE_API_VERSION_3_2: * Camera modules that may contain version 3.2 devices must implement at * least version 2.2 of the camera module interface (as defined by * camera_module_t.common.module_api_version). * * <= CAMERA_DEVICE_API_VERSION_3_1: * Camera modules that may contain version 3.1 (or 3.0) devices must * implement at least version 2.0 of the camera module interface * (as defined by camera_module_t.common.module_api_version). * * See camera_common.h for more versioning details. * * Documentation index: * S1. Version history * S2. Startup and operation sequencing * S3. Operational modes * S4. 3A modes and state machines * S5. Cropping * S6. Error management * S7. Key Performance Indicator (KPI) glossary * S8. Sample Use Cases * S9. Notes on Controls and Metadata * S10. Reprocessing flow and controls */ /** * S1. Version history: * * 1.0: Initial Android camera HAL (Android 4.0) [camera.h]: * * - Converted from C++ CameraHardwareInterface abstraction layer. * * - Supports android.hardware.Camera API. * * 2.0: Initial release of expanded-capability HAL (Android 4.2) [camera2.h]: * * - Sufficient for implementing existing android.hardware.Camera API. * * - Allows for ZSL queue in camera service layer * * - Not tested for any new features such manual capture control, Bayer RAW * capture, reprocessing of RAW data. * * 3.0: First revision of expanded-capability HAL: * * - Major version change since the ABI is completely different. No change to * the required hardware capabilities or operational model from 2.0. * * - Reworked input request and stream queue interfaces: Framework calls into * HAL with next request and stream buffers already dequeued. Sync framework * support is included, necessary for efficient implementations. * * - Moved triggers into requests, most notifications into results. * * - Consolidated all callbacks into framework into one structure, and all * setup methods into a single initialize() call. * * - Made stream configuration into a single call to simplify stream * management. Bidirectional streams replace STREAM_FROM_STREAM construct. * * - Limited mode semantics for older/limited hardware devices. * * 3.1: Minor revision of expanded-capability HAL: * * - configure_streams passes consumer usage flags to the HAL. * * - flush call to drop all in-flight requests/buffers as fast as possible. * * 3.2: Minor revision of expanded-capability HAL: * * - Deprecates get_metadata_vendor_tag_ops. Please use get_vendor_tag_ops * in camera_common.h instead. * * - register_stream_buffers deprecated. All gralloc buffers provided * by framework to HAL in process_capture_request may be new at any time. * * - add partial result support. process_capture_result may be called * multiple times with a subset of the available result before the full * result is available. * * - add manual template to camera3_request_template. The applications may * use this template to control the capture settings directly. * * - Rework the bidirectional and input stream specifications. * * - change the input buffer return path. The buffer is returned in * process_capture_result instead of process_capture_request. * * 3.3: Minor revision of expanded-capability HAL: * * - OPAQUE and YUV reprocessing API updates. * * - Basic support for depth output buffers. * * - Addition of data_space field to camera3_stream_t. * * - Addition of rotation field to camera3_stream_t. * * - Addition of camera3 stream configuration operation mode to camera3_stream_configuration_t * * 3.4: Minor additions to supported metadata and changes to data_space support * * - Add ANDROID_SENSOR_OPAQUE_RAW_SIZE static metadata as mandatory if * RAW_OPAQUE format is supported. * * - Add ANDROID_CONTROL_POST_RAW_SENSITIVITY_BOOST_RANGE static metadata as * mandatory if any RAW format is supported * * - Switch camera3_stream_t data_space field to a more flexible definition, * using the version 0 definition of dataspace encoding. * * - General metadata additions which are available to use for HALv3.2 or * newer: * - ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL_3 * - ANDROID_CONTROL_POST_RAW_SENSITIVITY_BOOST * - ANDROID_CONTROL_POST_RAW_SENSITIVITY_BOOST_RANGE * - ANDROID_SENSOR_DYNAMIC_BLACK_LEVEL * - ANDROID_SENSOR_DYNAMIC_WHITE_LEVEL * - ANDROID_SENSOR_OPAQUE_RAW_SIZE * - ANDROID_SENSOR_OPTICAL_BLACK_REGIONS */ /** * S2. Startup and general expected operation sequence: * * 1. Framework calls camera_module_t->common.open(), which returns a * hardware_device_t structure. * * 2. Framework inspects the hardware_device_t->version field, and instantiates * the appropriate handler for that version of the camera hardware device. In * case the version is CAMERA_DEVICE_API_VERSION_3_0, the device is cast to * a camera3_device_t. * * 3. Framework calls camera3_device_t->ops->initialize() with the framework * callback function pointers. This will only be called this one time after * open(), before any other functions in the ops structure are called. * * 4. The framework calls camera3_device_t->ops->configure_streams() with a list * of input/output streams to the HAL device. * * 5. <= CAMERA_DEVICE_API_VERSION_3_1: * * The framework allocates gralloc buffers and calls * camera3_device_t->ops->register_stream_buffers() for at least one of the * output streams listed in configure_streams. The same stream is registered * only once. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * camera3_device_t->ops->register_stream_buffers() is not called and must * be NULL. * * 6. The framework requests default settings for some number of use cases with * calls to camera3_device_t->ops->construct_default_request_settings(). This * may occur any time after step 3. * * 7. The framework constructs and sends the first capture request to the HAL, * with settings based on one of the sets of default settings, and with at * least one output stream, which has been registered earlier by the * framework. This is sent to the HAL with * camera3_device_t->ops->process_capture_request(). The HAL must block the * return of this call until it is ready for the next request to be sent. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * The buffer_handle_t provided in the camera3_stream_buffer_t array * in the camera3_capture_request_t may be new and never-before-seen * by the HAL on any given new request. * * 8. The framework continues to submit requests, and call * construct_default_request_settings to get default settings buffers for * other use cases. * * <= CAMERA_DEVICE_API_VERSION_3_1: * * The framework may call register_stream_buffers() at this time for * not-yet-registered streams. * * 9. When the capture of a request begins (sensor starts exposing for the * capture) or processing a reprocess request begins, the HAL * calls camera3_callback_ops_t->notify() with the SHUTTER event, including * the frame number and the timestamp for start of exposure. For a reprocess * request, the timestamp must be the start of exposure of the input image * which can be looked up with android.sensor.timestamp from * camera3_capture_request_t.settings when process_capture_request() is * called. * * <= CAMERA_DEVICE_API_VERSION_3_1: * * This notify call must be made before the first call to * process_capture_result() for that frame number. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * The camera3_callback_ops_t->notify() call with the SHUTTER event should * be made as early as possible since the framework will be unable to * deliver gralloc buffers to the application layer (for that frame) until * it has a valid timestamp for the start of exposure (or the input image's * start of exposure for a reprocess request). * * Both partial metadata results and the gralloc buffers may be sent to the * framework at any time before or after the SHUTTER event. * * 10. After some pipeline delay, the HAL begins to return completed captures to * the framework with camera3_callback_ops_t->process_capture_result(). These * are returned in the same order as the requests were submitted. Multiple * requests can be in flight at once, depending on the pipeline depth of the * camera HAL device. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * Once a buffer is returned by process_capture_result as part of the * camera3_stream_buffer_t array, and the fence specified by release_fence * has been signaled (this is a no-op for -1 fences), the ownership of that * buffer is considered to be transferred back to the framework. After that, * the HAL must no longer retain that particular buffer, and the * framework may clean up the memory for it immediately. * * process_capture_result may be called multiple times for a single frame, * each time with a new disjoint piece of metadata and/or set of gralloc * buffers. The framework will accumulate these partial metadata results * into one result. * * In particular, it is legal for a process_capture_result to be called * simultaneously for both a frame N and a frame N+1 as long as the * above rule holds for gralloc buffers (both input and output). * * 11. After some time, the framework may stop submitting new requests, wait for * the existing captures to complete (all buffers filled, all results * returned), and then call configure_streams() again. This resets the camera * hardware and pipeline for a new set of input/output streams. Some streams * may be reused from the previous configuration; if these streams' buffers * had already been registered with the HAL, they will not be registered * again. The framework then continues from step 7, if at least one * registered output stream remains (otherwise, step 5 is required first). * * 12. Alternatively, the framework may call camera3_device_t->common->close() * to end the camera session. This may be called at any time when no other * calls from the framework are active, although the call may block until all * in-flight captures have completed (all results returned, all buffers * filled). After the close call returns, no more calls to the * camera3_callback_ops_t functions are allowed from the HAL. Once the * close() call is underway, the framework may not call any other HAL device * functions. * * 13. In case of an error or other asynchronous event, the HAL must call * camera3_callback_ops_t->notify() with the appropriate error/event * message. After returning from a fatal device-wide error notification, the * HAL should act as if close() had been called on it. However, the HAL must * either cancel or complete all outstanding captures before calling * notify(), so that once notify() is called with a fatal error, the * framework will not receive further callbacks from the device. Methods * besides close() should return -ENODEV or NULL after the notify() method * returns from a fatal error message. */ /** * S3. Operational modes: * * The camera 3 HAL device can implement one of two possible operational modes; * limited and full. Full support is expected from new higher-end * devices. Limited mode has hardware requirements roughly in line with those * for a camera HAL device v1 implementation, and is expected from older or * inexpensive devices. Full is a strict superset of limited, and they share the * same essential operational flow, as documented above. * * The HAL must indicate its level of support with the * android.info.supportedHardwareLevel static metadata entry, with 0 indicating * limited mode, and 1 indicating full mode support. * * Roughly speaking, limited-mode devices do not allow for application control * of capture settings (3A control only), high-rate capture of high-resolution * images, raw sensor readout, or support for YUV output streams above maximum * recording resolution (JPEG only for large images). * * ** Details of limited mode behavior: * * - Limited-mode devices do not need to implement accurate synchronization * between capture request settings and the actual image data * captured. Instead, changes to settings may take effect some time in the * future, and possibly not for the same output frame for each settings * entry. Rapid changes in settings may result in some settings never being * used for a capture. However, captures that include high-resolution output * buffers ( > 1080p ) have to use the settings as specified (but see below * for processing rate). * * - Limited-mode devices do not need to support most of the * settings/result/static info metadata. Specifically, only the following settings * are expected to be consumed or produced by a limited-mode HAL device: * * android.control.aeAntibandingMode (controls and dynamic) * android.control.aeExposureCompensation (controls and dynamic) * android.control.aeLock (controls and dynamic) * android.control.aeMode (controls and dynamic) * android.control.aeRegions (controls and dynamic) * android.control.aeTargetFpsRange (controls and dynamic) * android.control.aePrecaptureTrigger (controls and dynamic) * android.control.afMode (controls and dynamic) * android.control.afRegions (controls and dynamic) * android.control.awbLock (controls and dynamic) * android.control.awbMode (controls and dynamic) * android.control.awbRegions (controls and dynamic) * android.control.captureIntent (controls and dynamic) * android.control.effectMode (controls and dynamic) * android.control.mode (controls and dynamic) * android.control.sceneMode (controls and dynamic) * android.control.videoStabilizationMode (controls and dynamic) * android.control.aeAvailableAntibandingModes (static) * android.control.aeAvailableModes (static) * android.control.aeAvailableTargetFpsRanges (static) * android.control.aeCompensationRange (static) * android.control.aeCompensationStep (static) * android.control.afAvailableModes (static) * android.control.availableEffects (static) * android.control.availableSceneModes (static) * android.control.availableVideoStabilizationModes (static) * android.control.awbAvailableModes (static) * android.control.maxRegions (static) * android.control.sceneModeOverrides (static) * android.control.aeState (dynamic) * android.control.afState (dynamic) * android.control.awbState (dynamic) * * android.flash.mode (controls and dynamic) * android.flash.info.available (static) * * android.info.supportedHardwareLevel (static) * * android.jpeg.gpsCoordinates (controls and dynamic) * android.jpeg.gpsProcessingMethod (controls and dynamic) * android.jpeg.gpsTimestamp (controls and dynamic) * android.jpeg.orientation (controls and dynamic) * android.jpeg.quality (controls and dynamic) * android.jpeg.thumbnailQuality (controls and dynamic) * android.jpeg.thumbnailSize (controls and dynamic) * android.jpeg.availableThumbnailSizes (static) * android.jpeg.maxSize (static) * * android.lens.info.minimumFocusDistance (static) * * android.request.id (controls and dynamic) * * android.scaler.cropRegion (controls and dynamic) * android.scaler.availableStreamConfigurations (static) * android.scaler.availableMinFrameDurations (static) * android.scaler.availableStallDurations (static) * android.scaler.availableMaxDigitalZoom (static) * android.scaler.maxDigitalZoom (static) * android.scaler.croppingType (static) * * android.sensor.orientation (static) * android.sensor.timestamp (dynamic) * * android.statistics.faceDetectMode (controls and dynamic) * android.statistics.info.availableFaceDetectModes (static) * android.statistics.faceIds (dynamic) * android.statistics.faceLandmarks (dynamic) * android.statistics.faceRectangles (dynamic) * android.statistics.faceScores (dynamic) * * android.sync.frameNumber (dynamic) * android.sync.maxLatency (static) * * - Captures in limited mode that include high-resolution (> 1080p) output * buffers may block in process_capture_request() until all the output buffers * have been filled. A full-mode HAL device must process sequences of * high-resolution requests at the rate indicated in the static metadata for * that pixel format. The HAL must still call process_capture_result() to * provide the output; the framework must simply be prepared for * process_capture_request() to block until after process_capture_result() for * that request completes for high-resolution captures for limited-mode * devices. * * - Full-mode devices must support below additional capabilities: * - 30fps at maximum resolution is preferred, more than 20fps is required. * - Per frame control (android.sync.maxLatency == PER_FRAME_CONTROL). * - Sensor manual control metadata. See MANUAL_SENSOR defined in * android.request.availableCapabilities. * - Post-processing manual control metadata. See MANUAL_POST_PROCESSING defined * in android.request.availableCapabilities. * */ /** * S4. 3A modes and state machines: * * While the actual 3A algorithms are up to the HAL implementation, a high-level * state machine description is defined by the HAL interface, to allow the HAL * device and the framework to communicate about the current state of 3A, and to * trigger 3A events. * * When the device is opened, all the individual 3A states must be * STATE_INACTIVE. Stream configuration does not reset 3A. For example, locked * focus must be maintained across the configure() call. * * Triggering a 3A action involves simply setting the relevant trigger entry in * the settings for the next request to indicate start of trigger. For example, * the trigger for starting an autofocus scan is setting the entry * ANDROID_CONTROL_AF_TRIGGER to ANDROID_CONTROL_AF_TRIGGER_START for one * request, and cancelling an autofocus scan is triggered by setting * ANDROID_CONTROL_AF_TRIGGER to ANDROID_CONTRL_AF_TRIGGER_CANCEL. Otherwise, * the entry will not exist, or be set to ANDROID_CONTROL_AF_TRIGGER_IDLE. Each * request with a trigger entry set to a non-IDLE value will be treated as an * independent triggering event. * * At the top level, 3A is controlled by the ANDROID_CONTROL_MODE setting, which * selects between no 3A (ANDROID_CONTROL_MODE_OFF), normal AUTO mode * (ANDROID_CONTROL_MODE_AUTO), and using the scene mode setting * (ANDROID_CONTROL_USE_SCENE_MODE). * * - In OFF mode, each of the individual AE/AF/AWB modes are effectively OFF, * and none of the capture controls may be overridden by the 3A routines. * * - In AUTO mode, Auto-focus, auto-exposure, and auto-whitebalance all run * their own independent algorithms, and have their own mode, state, and * trigger metadata entries, as listed in the next section. * * - In USE_SCENE_MODE, the value of the ANDROID_CONTROL_SCENE_MODE entry must * be used to determine the behavior of 3A routines. In SCENE_MODEs other than * FACE_PRIORITY, the HAL must override the values of * ANDROId_CONTROL_AE/AWB/AF_MODE to be the mode it prefers for the selected * SCENE_MODE. For example, the HAL may prefer SCENE_MODE_NIGHT to use * CONTINUOUS_FOCUS AF mode. Any user selection of AE/AWB/AF_MODE when scene * must be ignored for these scene modes. * * - For SCENE_MODE_FACE_PRIORITY, the AE/AWB/AF_MODE controls work as in * ANDROID_CONTROL_MODE_AUTO, but the 3A routines must bias toward metering * and focusing on any detected faces in the scene. * * S4.1. Auto-focus settings and result entries: * * Main metadata entries: * * ANDROID_CONTROL_AF_MODE: Control for selecting the current autofocus * mode. Set by the framework in the request settings. * * AF_MODE_OFF: AF is disabled; the framework/app directly controls lens * position. * * AF_MODE_AUTO: Single-sweep autofocus. No lens movement unless AF is * triggered. * * AF_MODE_MACRO: Single-sweep up-close autofocus. No lens movement unless * AF is triggered. * * AF_MODE_CONTINUOUS_VIDEO: Smooth continuous focusing, for recording * video. Triggering immediately locks focus in current * position. Canceling resumes cotinuous focusing. * * AF_MODE_CONTINUOUS_PICTURE: Fast continuous focusing, for * zero-shutter-lag still capture. Triggering locks focus once currently * active sweep concludes. Canceling resumes continuous focusing. * * AF_MODE_EDOF: Advanced extended depth of field focusing. There is no * autofocus scan, so triggering one or canceling one has no effect. * Images are focused automatically by the HAL. * * ANDROID_CONTROL_AF_STATE: Dynamic metadata describing the current AF * algorithm state, reported by the HAL in the result metadata. * * AF_STATE_INACTIVE: No focusing has been done, or algorithm was * reset. Lens is not moving. Always the state for MODE_OFF or MODE_EDOF. * When the device is opened, it must start in this state. * * AF_STATE_PASSIVE_SCAN: A continuous focus algorithm is currently scanning * for good focus. The lens is moving. * * AF_STATE_PASSIVE_FOCUSED: A continuous focus algorithm believes it is * well focused. The lens is not moving. The HAL may spontaneously leave * this state. * * AF_STATE_PASSIVE_UNFOCUSED: A continuous focus algorithm believes it is * not well focused. The lens is not moving. The HAL may spontaneously * leave this state. * * AF_STATE_ACTIVE_SCAN: A scan triggered by the user is underway. * * AF_STATE_FOCUSED_LOCKED: The AF algorithm believes it is focused. The * lens is not moving. * * AF_STATE_NOT_FOCUSED_LOCKED: The AF algorithm has been unable to * focus. The lens is not moving. * * ANDROID_CONTROL_AF_TRIGGER: Control for starting an autofocus scan, the * meaning of which is mode- and state- dependent. Set by the framework in * the request settings. * * AF_TRIGGER_IDLE: No current trigger. * * AF_TRIGGER_START: Trigger start of AF scan. Effect is mode and state * dependent. * * AF_TRIGGER_CANCEL: Cancel current AF scan if any, and reset algorithm to * default. * * Additional metadata entries: * * ANDROID_CONTROL_AF_REGIONS: Control for selecting the regions of the FOV * that should be used to determine good focus. This applies to all AF * modes that scan for focus. Set by the framework in the request * settings. * * S4.2. Auto-exposure settings and result entries: * * Main metadata entries: * * ANDROID_CONTROL_AE_MODE: Control for selecting the current auto-exposure * mode. Set by the framework in the request settings. * * AE_MODE_OFF: Autoexposure is disabled; the user controls exposure, gain, * frame duration, and flash. * * AE_MODE_ON: Standard autoexposure, with flash control disabled. User may * set flash to fire or to torch mode. * * AE_MODE_ON_AUTO_FLASH: Standard autoexposure, with flash on at HAL's * discretion for precapture and still capture. User control of flash * disabled. * * AE_MODE_ON_ALWAYS_FLASH: Standard autoexposure, with flash always fired * for capture, and at HAL's discretion for precapture.. User control of * flash disabled. * * AE_MODE_ON_AUTO_FLASH_REDEYE: Standard autoexposure, with flash on at * HAL's discretion for precapture and still capture. Use a flash burst * at end of precapture sequence to reduce redeye in the final * picture. User control of flash disabled. * * ANDROID_CONTROL_AE_STATE: Dynamic metadata describing the current AE * algorithm state, reported by the HAL in the result metadata. * * AE_STATE_INACTIVE: Initial AE state after mode switch. When the device is * opened, it must start in this state. * * AE_STATE_SEARCHING: AE is not converged to a good value, and is adjusting * exposure parameters. * * AE_STATE_CONVERGED: AE has found good exposure values for the current * scene, and the exposure parameters are not changing. HAL may * spontaneously leave this state to search for better solution. * * AE_STATE_LOCKED: AE has been locked with the AE_LOCK control. Exposure * values are not changing. * * AE_STATE_FLASH_REQUIRED: The HAL has converged exposure, but believes * flash is required for a sufficiently bright picture. Used for * determining if a zero-shutter-lag frame can be used. * * AE_STATE_PRECAPTURE: The HAL is in the middle of a precapture * sequence. Depending on AE mode, this mode may involve firing the * flash for metering, or a burst of flash pulses for redeye reduction. * * ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER: Control for starting a metering * sequence before capturing a high-quality image. Set by the framework in * the request settings. * * PRECAPTURE_TRIGGER_IDLE: No current trigger. * * PRECAPTURE_TRIGGER_START: Start a precapture sequence. The HAL should * use the subsequent requests to measure good exposure/white balance * for an upcoming high-resolution capture. * * Additional metadata entries: * * ANDROID_CONTROL_AE_LOCK: Control for locking AE controls to their current * values * * ANDROID_CONTROL_AE_EXPOSURE_COMPENSATION: Control for adjusting AE * algorithm target brightness point. * * ANDROID_CONTROL_AE_TARGET_FPS_RANGE: Control for selecting the target frame * rate range for the AE algorithm. The AE routine cannot change the frame * rate to be outside these bounds. * * ANDROID_CONTROL_AE_REGIONS: Control for selecting the regions of the FOV * that should be used to determine good exposure levels. This applies to * all AE modes besides OFF. * * S4.3. Auto-whitebalance settings and result entries: * * Main metadata entries: * * ANDROID_CONTROL_AWB_MODE: Control for selecting the current white-balance * mode. * * AWB_MODE_OFF: Auto-whitebalance is disabled. User controls color matrix. * * AWB_MODE_AUTO: Automatic white balance is enabled; 3A controls color * transform, possibly using more complex transforms than a simple * matrix. * * AWB_MODE_INCANDESCENT: Fixed white balance settings good for indoor * incandescent (tungsten) lighting, roughly 2700K. * * AWB_MODE_FLUORESCENT: Fixed white balance settings good for fluorescent * lighting, roughly 5000K. * * AWB_MODE_WARM_FLUORESCENT: Fixed white balance settings good for * fluorescent lighting, roughly 3000K. * * AWB_MODE_DAYLIGHT: Fixed white balance settings good for daylight, * roughly 5500K. * * AWB_MODE_CLOUDY_DAYLIGHT: Fixed white balance settings good for clouded * daylight, roughly 6500K. * * AWB_MODE_TWILIGHT: Fixed white balance settings good for * near-sunset/sunrise, roughly 15000K. * * AWB_MODE_SHADE: Fixed white balance settings good for areas indirectly * lit by the sun, roughly 7500K. * * ANDROID_CONTROL_AWB_STATE: Dynamic metadata describing the current AWB * algorithm state, reported by the HAL in the result metadata. * * AWB_STATE_INACTIVE: Initial AWB state after mode switch. When the device * is opened, it must start in this state. * * AWB_STATE_SEARCHING: AWB is not converged to a good value, and is * changing color adjustment parameters. * * AWB_STATE_CONVERGED: AWB has found good color adjustment values for the * current scene, and the parameters are not changing. HAL may * spontaneously leave this state to search for better solution. * * AWB_STATE_LOCKED: AWB has been locked with the AWB_LOCK control. Color * adjustment values are not changing. * * Additional metadata entries: * * ANDROID_CONTROL_AWB_LOCK: Control for locking AWB color adjustments to * their current values. * * ANDROID_CONTROL_AWB_REGIONS: Control for selecting the regions of the FOV * that should be used to determine good color balance. This applies only * to auto-WB mode. * * S4.4. General state machine transition notes * * Switching between AF, AE, or AWB modes always resets the algorithm's state * to INACTIVE. Similarly, switching between CONTROL_MODE or * CONTROL_SCENE_MODE if CONTROL_MODE == USE_SCENE_MODE resets all the * algorithm states to INACTIVE. * * The tables below are per-mode. * * S4.5. AF state machines * * when enabling AF or changing AF mode *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| Any | AF mode change| INACTIVE | | *+--------------------+---------------+--------------------+------------------+ * * mode = AF_MODE_OFF or AF_MODE_EDOF *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | | INACTIVE | Never changes | *+--------------------+---------------+--------------------+------------------+ * * mode = AF_MODE_AUTO or AF_MODE_MACRO *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | AF_TRIGGER | ACTIVE_SCAN | Start AF sweep | *| | | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| ACTIVE_SCAN | AF sweep done | FOCUSED_LOCKED | If AF successful | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| ACTIVE_SCAN | AF sweep done | NOT_FOCUSED_LOCKED | If AF successful | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| ACTIVE_SCAN | AF_CANCEL | INACTIVE | Cancel/reset AF | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Cancel/reset AF | *+--------------------+---------------+--------------------+------------------+ *| FOCUSED_LOCKED | AF_TRIGGER | ACTIVE_SCAN | Start new sweep | *| | | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| NOT_FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Cancel/reset AF | *+--------------------+---------------+--------------------+------------------+ *| NOT_FOCUSED_LOCKED | AF_TRIGGER | ACTIVE_SCAN | Start new sweep | *| | | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| All states | mode change | INACTIVE | | *+--------------------+---------------+--------------------+------------------+ * * mode = AF_MODE_CONTINUOUS_VIDEO *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | HAL initiates | PASSIVE_SCAN | Start AF scan | *| | new scan | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | AF_TRIGGER | NOT_FOCUSED_LOCKED | AF state query | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | HAL completes | PASSIVE_FOCUSED | End AF scan | *| | current scan | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | HAL fails | PASSIVE_UNFOCUSED | End AF scan | *| | current scan | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | AF_TRIGGER | FOCUSED_LOCKED | Immediate trans. | *| | | | if focus is good | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | AF_TRIGGER | NOT_FOCUSED_LOCKED | Immediate trans. | *| | | | if focus is bad | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | AF_CANCEL | INACTIVE | Reset lens | *| | | | position | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_FOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan | *| | new scan | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_UNFOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan | *| | new scan | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_FOCUSED | AF_TRIGGER | FOCUSED_LOCKED | Immediate trans. | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_UNFOCUSED | AF_TRIGGER | NOT_FOCUSED_LOCKED | Immediate trans. | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| FOCUSED_LOCKED | AF_TRIGGER | FOCUSED_LOCKED | No effect | *+--------------------+---------------+--------------------+------------------+ *| FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan | *+--------------------+---------------+--------------------+------------------+ *| NOT_FOCUSED_LOCKED | AF_TRIGGER | NOT_FOCUSED_LOCKED | No effect | *+--------------------+---------------+--------------------+------------------+ *| NOT_FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan | *+--------------------+---------------+--------------------+------------------+ * * mode = AF_MODE_CONTINUOUS_PICTURE *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | HAL initiates | PASSIVE_SCAN | Start AF scan | *| | new scan | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | AF_TRIGGER | NOT_FOCUSED_LOCKED | AF state query | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | HAL completes | PASSIVE_FOCUSED | End AF scan | *| | current scan | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | HAL fails | PASSIVE_UNFOCUSED | End AF scan | *| | current scan | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | AF_TRIGGER | FOCUSED_LOCKED | Eventual trans. | *| | | | once focus good | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | AF_TRIGGER | NOT_FOCUSED_LOCKED | Eventual trans. | *| | | | if cannot focus | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_SCAN | AF_CANCEL | INACTIVE | Reset lens | *| | | | position | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_FOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan | *| | new scan | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_UNFOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan | *| | new scan | | Lens now moving | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_FOCUSED | AF_TRIGGER | FOCUSED_LOCKED | Immediate trans. | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| PASSIVE_UNFOCUSED | AF_TRIGGER | NOT_FOCUSED_LOCKED | Immediate trans. | *| | | | Lens now locked | *+--------------------+---------------+--------------------+------------------+ *| FOCUSED_LOCKED | AF_TRIGGER | FOCUSED_LOCKED | No effect | *+--------------------+---------------+--------------------+------------------+ *| FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan | *+--------------------+---------------+--------------------+------------------+ *| NOT_FOCUSED_LOCKED | AF_TRIGGER | NOT_FOCUSED_LOCKED | No effect | *+--------------------+---------------+--------------------+------------------+ *| NOT_FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan | *+--------------------+---------------+--------------------+------------------+ * * S4.6. AE and AWB state machines * * The AE and AWB state machines are mostly identical. AE has additional * FLASH_REQUIRED and PRECAPTURE states. So rows below that refer to those two * states should be ignored for the AWB state machine. * * when enabling AE/AWB or changing AE/AWB mode *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| Any | mode change | INACTIVE | | *+--------------------+---------------+--------------------+------------------+ * * mode = AE_MODE_OFF / AWB mode not AUTO *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | | INACTIVE | AE/AWB disabled | *+--------------------+---------------+--------------------+------------------+ * * mode = AE_MODE_ON_* / AWB_MODE_AUTO *| state | trans. cause | new state | notes | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | HAL initiates | SEARCHING | | *| | AE/AWB scan | | | *+--------------------+---------------+--------------------+------------------+ *| INACTIVE | AE/AWB_LOCK | LOCKED | values locked | *| | on | | | *+--------------------+---------------+--------------------+------------------+ *| SEARCHING | HAL finishes | CONVERGED | good values, not | *| | AE/AWB scan | | changing | *+--------------------+---------------+--------------------+------------------+ *| SEARCHING | HAL finishes | FLASH_REQUIRED | converged but too| *| | AE scan | | dark w/o flash | *+--------------------+---------------+--------------------+------------------+ *| SEARCHING | AE/AWB_LOCK | LOCKED | values locked | *| | on | | | *+--------------------+---------------+--------------------+------------------+ *| CONVERGED | HAL initiates | SEARCHING | values locked | *| | AE/AWB scan | | | *+--------------------+---------------+--------------------+------------------+ *| CONVERGED | AE/AWB_LOCK | LOCKED | values locked | *| | on | | | *+--------------------+---------------+--------------------+------------------+ *| FLASH_REQUIRED | HAL initiates | SEARCHING | values locked | *| | AE/AWB scan | | | *+--------------------+---------------+--------------------+------------------+ *| FLASH_REQUIRED | AE/AWB_LOCK | LOCKED | values locked | *| | on | | | *+--------------------+---------------+--------------------+------------------+ *| LOCKED | AE/AWB_LOCK | SEARCHING | values not good | *| | off | | after unlock | *+--------------------+---------------+--------------------+------------------+ *| LOCKED | AE/AWB_LOCK | CONVERGED | values good | *| | off | | after unlock | *+--------------------+---------------+--------------------+------------------+ *| LOCKED | AE_LOCK | FLASH_REQUIRED | exposure good, | *| | off | | but too dark | *+--------------------+---------------+--------------------+------------------+ *| All AE states | PRECAPTURE_ | PRECAPTURE | Start precapture | *| | START | | sequence | *+--------------------+---------------+--------------------+------------------+ *| PRECAPTURE | Sequence done.| CONVERGED | Ready for high- | *| | AE_LOCK off | | quality capture | *+--------------------+---------------+--------------------+------------------+ *| PRECAPTURE | Sequence done.| LOCKED | Ready for high- | *| | AE_LOCK on | | quality capture | *+--------------------+---------------+--------------------+------------------+ * */ /** * S5. Cropping: * * Cropping of the full pixel array (for digital zoom and other use cases where * a smaller FOV is desirable) is communicated through the * ANDROID_SCALER_CROP_REGION setting. This is a per-request setting, and can * change on a per-request basis, which is critical for implementing smooth * digital zoom. * * The region is defined as a rectangle (x, y, width, height), with (x, y) * describing the top-left corner of the rectangle. The rectangle is defined on * the coordinate system of the sensor active pixel array, with (0,0) being the * top-left pixel of the active pixel array. Therefore, the width and height * cannot be larger than the dimensions reported in the * ANDROID_SENSOR_ACTIVE_PIXEL_ARRAY static info field. The minimum allowed * width and height are reported by the HAL through the * ANDROID_SCALER_MAX_DIGITAL_ZOOM static info field, which describes the * maximum supported zoom factor. Therefore, the minimum crop region width and * height are: * * {width, height} = * { floor(ANDROID_SENSOR_ACTIVE_PIXEL_ARRAY[0] / * ANDROID_SCALER_MAX_DIGITAL_ZOOM), * floor(ANDROID_SENSOR_ACTIVE_PIXEL_ARRAY[1] / * ANDROID_SCALER_MAX_DIGITAL_ZOOM) } * * If the crop region needs to fulfill specific requirements (for example, it * needs to start on even coordinates, and its width/height needs to be even), * the HAL must do the necessary rounding and write out the final crop region * used in the output result metadata. Similarly, if the HAL implements video * stabilization, it must adjust the result crop region to describe the region * actually included in the output after video stabilization is applied. In * general, a camera-using application must be able to determine the field of * view it is receiving based on the crop region, the dimensions of the image * sensor, and the lens focal length. * * It is assumed that the cropping is applied after raw to other color space * conversion. Raw streams (RAW16 and RAW_OPAQUE) don't have this conversion stage, * and are not croppable. Therefore, the crop region must be ignored by the HAL * for raw streams. * * Since the crop region applies to all non-raw streams, which may have different aspect * ratios than the crop region, the exact sensor region used for each stream may * be smaller than the crop region. Specifically, each stream should maintain * square pixels and its aspect ratio by minimally further cropping the defined * crop region. If the stream's aspect ratio is wider than the crop region, the * stream should be further cropped vertically, and if the stream's aspect ratio * is narrower than the crop region, the stream should be further cropped * horizontally. * * In all cases, the stream crop must be centered within the full crop region, * and each stream is only either cropped horizontally or vertical relative to * the full crop region, never both. * * For example, if two streams are defined, a 640x480 stream (4:3 aspect), and a * 1280x720 stream (16:9 aspect), below demonstrates the expected output regions * for each stream for a few sample crop regions, on a hypothetical 3 MP (2000 x * 1500 pixel array) sensor. * * Crop region: (500, 375, 1000, 750) (4:3 aspect ratio) * * 640x480 stream crop: (500, 375, 1000, 750) (equal to crop region) * 1280x720 stream crop: (500, 469, 1000, 562) (marked with =) * * 0 1000 2000 * +---------+---------+---------+----------+ * | Active pixel array | * | | * | | * + +-------------------+ + 375 * | | | | * | O===================O | * | I 1280x720 stream I | * + I I + 750 * | I I | * | O===================O | * | | | | * + +-------------------+ + 1125 * | Crop region, 640x480 stream | * | | * | | * +---------+---------+---------+----------+ 1500 * * Crop region: (500, 375, 1333, 750) (16:9 aspect ratio) * * 640x480 stream crop: (666, 375, 1000, 750) (marked with =) * 1280x720 stream crop: (500, 375, 1333, 750) (equal to crop region) * * 0 1000 2000 * +---------+---------+---------+----------+ * | Active pixel array | * | | * | | * + +---O==================O---+ + 375 * | | I 640x480 stream I | | * | | I I | | * | | I I | | * + | I I | + 750 * | | I I | | * | | I I | | * | | I I | | * + +---O==================O---+ + 1125 * | Crop region, 1280x720 stream | * | | * | | * +---------+---------+---------+----------+ 1500 * * Crop region: (500, 375, 750, 750) (1:1 aspect ratio) * * 640x480 stream crop: (500, 469, 750, 562) (marked with =) * 1280x720 stream crop: (500, 543, 750, 414) (marged with #) * * 0 1000 2000 * +---------+---------+---------+----------+ * | Active pixel array | * | | * | | * + +--------------+ + 375 * | O==============O | * | ################ | * | # # | * + # # + 750 * | # # | * | ################ 1280x720 | * | O==============O 640x480 | * + +--------------+ + 1125 * | Crop region | * | | * | | * +---------+---------+---------+----------+ 1500 * * And a final example, a 1024x1024 square aspect ratio stream instead of the * 480p stream: * * Crop region: (500, 375, 1000, 750) (4:3 aspect ratio) * * 1024x1024 stream crop: (625, 375, 750, 750) (marked with #) * 1280x720 stream crop: (500, 469, 1000, 562) (marked with =) * * 0 1000 2000 * +---------+---------+---------+----------+ * | Active pixel array | * | | * | 1024x1024 stream | * + +--###############--+ + 375 * | | # # | | * | O===================O | * | I 1280x720 stream I | * + I I + 750 * | I I | * | O===================O | * | | # # | | * + +--###############--+ + 1125 * | Crop region | * | | * | | * +---------+---------+---------+----------+ 1500 * */ /** * S6. Error management: * * Camera HAL device ops functions that have a return value will all return * -ENODEV / NULL in case of a serious error. This means the device cannot * continue operation, and must be closed by the framework. Once this error is * returned by some method, or if notify() is called with ERROR_DEVICE, only * the close() method can be called successfully. All other methods will return * -ENODEV / NULL. * * If a device op is called in the wrong sequence, for example if the framework * calls configure_streams() is called before initialize(), the device must * return -ENOSYS from the call, and do nothing. * * Transient errors in image capture must be reported through notify() as follows: * * - The failure of an entire capture to occur must be reported by the HAL by * calling notify() with ERROR_REQUEST. Individual errors for the result * metadata or the output buffers must not be reported in this case. * * - If the metadata for a capture cannot be produced, but some image buffers * were filled, the HAL must call notify() with ERROR_RESULT. * * - If an output image buffer could not be filled, but either the metadata was * produced or some other buffers were filled, the HAL must call notify() with * ERROR_BUFFER for each failed buffer. * * In each of these transient failure cases, the HAL must still call * process_capture_result, with valid output and input (if an input buffer was * submitted) buffer_handle_t. If the result metadata could not be produced, it * should be NULL. If some buffers could not be filled, they must be returned with * process_capture_result in the error state, their release fences must be set to * the acquire fences passed by the framework, or -1 if they have been waited on by * the HAL already. * * Invalid input arguments result in -EINVAL from the appropriate methods. In * that case, the framework must act as if that call had never been made. * */ /** * S7. Key Performance Indicator (KPI) glossary: * * This includes some critical definitions that are used by KPI metrics. * * Pipeline Latency: * For a given capture request, the duration from the framework calling * process_capture_request to the HAL sending capture result and all buffers * back by process_capture_result call. To make the Pipeline Latency measure * independent of frame rate, it is measured by frame count. * * For example, when frame rate is 30 (fps), the frame duration (time interval * between adjacent frame capture time) is 33 (ms). * If it takes 5 frames for framework to get the result and buffers back for * a given request, then the Pipeline Latency is 5 (frames), instead of * 5 x 33 = 165 (ms). * * The Pipeline Latency is determined by android.request.pipelineDepth and * android.request.pipelineMaxDepth, see their definitions for more details. * */ /** * S8. Sample Use Cases: * * This includes some typical use case examples the camera HAL may support. * * S8.1 Zero Shutter Lag (ZSL) with CAMERA3_STREAM_BIDIRECTIONAL stream. * * For this use case, the bidirectional stream will be used by the framework as follows: * * 1. The framework includes a buffer from this stream as output buffer in a * request as normal. * * 2. Once the HAL device returns a filled output buffer to the framework, * the framework may do one of two things with the filled buffer: * * 2. a. The framework uses the filled data, and returns the now-used buffer * to the stream queue for reuse. This behavior exactly matches the * OUTPUT type of stream. * * 2. b. The framework wants to reprocess the filled data, and uses the * buffer as an input buffer for a request. Once the HAL device has * used the reprocessing buffer, it then returns it to the * framework. The framework then returns the now-used buffer to the * stream queue for reuse. * * 3. The HAL device will be given the buffer again as an output buffer for * a request at some future point. * * For ZSL use case, the pixel format for bidirectional stream will be * HAL_PIXEL_FORMAT_RAW_OPAQUE or HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED if it * is listed in android.scaler.availableInputOutputFormatsMap. When * HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED is used, the gralloc * usage flags for the consumer endpoint will be set to GRALLOC_USAGE_HW_CAMERA_ZSL. * A configuration stream list that has BIDIRECTIONAL stream used as input, will * usually also have a distinct OUTPUT stream to get the reprocessing data. For example, * for the ZSL use case, the stream list might be configured with the following: * * - A HAL_PIXEL_FORMAT_RAW_OPAQUE bidirectional stream is used * as input. * - And a HAL_PIXEL_FORMAT_BLOB (JPEG) output stream. * * S8.2 ZSL (OPAQUE) reprocessing with CAMERA3_STREAM_INPUT stream. * * CAMERA_DEVICE_API_VERSION_3_3: * When OPAQUE_REPROCESSING capability is supported by the camera device, the INPUT stream * can be used for application/framework implemented use case like Zero Shutter Lag (ZSL). * This kind of stream will be used by the framework as follows: * * 1. Application/framework configures an opaque (RAW or YUV based) format output stream that is * used to produce the ZSL output buffers. The stream pixel format will be * HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED. * * 2. Application/framework configures an opaque format input stream that is used to * send the reprocessing ZSL buffers to the HAL. The stream pixel format will * also be HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED. * * 3. Application/framework configures a YUV/JPEG output stream that is used to receive the * reprocessed data. The stream pixel format will be YCbCr_420/HAL_PIXEL_FORMAT_BLOB. * * 4. Application/framework picks a ZSL buffer from the ZSL output stream when a ZSL capture is * issued by the application, and sends the data back as an input buffer in a * reprocessing request, then sends to the HAL for reprocessing. * * 5. The HAL sends back the output YUV/JPEG result to framework. * * The HAL can select the actual opaque buffer format and configure the ISP pipeline * appropriately based on the HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED format and * the gralloc usage flag GRALLOC_USAGE_HW_CAMERA_ZSL. * S8.3 YUV reprocessing with CAMERA3_STREAM_INPUT stream. * * When YUV reprocessing is supported by the HAL, the INPUT stream * can be used for the YUV reprocessing use cases like lucky-shot and image fusion. * This kind of stream will be used by the framework as follows: * * 1. Application/framework configures an YCbCr_420 format output stream that is * used to produce the output buffers. * * 2. Application/framework configures an YCbCr_420 format input stream that is used to * send the reprocessing YUV buffers to the HAL. * * 3. Application/framework configures a YUV/JPEG output stream that is used to receive the * reprocessed data. The stream pixel format will be YCbCr_420/HAL_PIXEL_FORMAT_BLOB. * * 4. Application/framework processes the output buffers (could be as simple as picking * an output buffer directly) from the output stream when a capture is issued, and sends * the data back as an input buffer in a reprocessing request, then sends to the HAL * for reprocessing. * * 5. The HAL sends back the output YUV/JPEG result to framework. * */ /** * S9. Notes on Controls and Metadata * * This section contains notes about the interpretation and usage of various metadata tags. * * S9.1 HIGH_QUALITY and FAST modes. * * Many camera post-processing blocks may be listed as having HIGH_QUALITY, * FAST, and OFF operating modes. These blocks will typically also have an * 'available modes' tag representing which of these operating modes are * available on a given device. The general policy regarding implementing * these modes is as follows: * * 1. Operating mode controls of hardware blocks that cannot be disabled * must not list OFF in their corresponding 'available modes' tags. * * 2. OFF will always be included in their corresponding 'available modes' * tag if it is possible to disable that hardware block. * * 3. FAST must always be included in the 'available modes' tags for all * post-processing blocks supported on the device. If a post-processing * block also has a slower and higher quality operating mode that does * not meet the framerate requirements for FAST mode, HIGH_QUALITY should * be included in the 'available modes' tag to represent this operating * mode. */ /** * S10. Reprocessing flow and controls * * This section describes the OPAQUE and YUV reprocessing flow and controls. OPAQUE reprocessing * uses an opaque format that is not directly application-visible, and the application can * only select some of the output buffers and send back to HAL for reprocessing, while YUV * reprocessing gives the application opportunity to process the buffers before reprocessing. * * S8 gives the stream configurations for the typical reprocessing uses cases, * this section specifies the buffer flow and controls in more details. * * S10.1 OPAQUE (typically for ZSL use case) reprocessing flow and controls * * For OPAQUE reprocessing (e.g. ZSL) use case, after the application creates the specific * output and input streams, runtime buffer flow and controls are specified as below: * * 1. Application starts output streaming by sending repeating requests for output * opaque buffers and preview. The buffers are held by an application * maintained circular buffer. The requests are based on CAMERA3_TEMPLATE_ZERO_SHUTTER_LAG * capture template, which should have all necessary settings that guarantee output * frame rate is not slowed down relative to sensor output frame rate. * * 2. When a capture is issued, the application selects one output buffer based * on application buffer selection logic, e.g. good AE and AF statistics etc. * Application then creates an reprocess request based on the capture result associated * with this selected buffer. The selected output buffer is now added to this reprocess * request as an input buffer, the output buffer of this reprocess request should be * either JPEG output buffer or YUV output buffer, or both, depending on the application * choice. * * 3. Application then alters the reprocess settings to get best image quality. The HAL must * support and only support below controls if the HAL support OPAQUE_REPROCESSING capability: * - android.jpeg.* (if JPEG buffer is included as one of the output) * - android.noiseReduction.mode (change to HIGH_QUALITY if it is supported) * - android.edge.mode (change to HIGH_QUALITY if it is supported) * All other controls must be ignored by the HAL. * 4. HAL processed the input buffer and return the output buffers in the capture results * as normal. * * S10.2 YUV reprocessing flow and controls * * The YUV reprocessing buffer flow is similar as OPAQUE reprocessing, with below difference: * * 1. Application may want to have finer granularity control of the intermediate YUV images * (before reprocessing). For example, application may choose * - android.noiseReduction.mode == MINIMAL * to make sure the no YUV domain noise reduction has applied to the output YUV buffers, * then it can do its own advanced noise reduction on them. For OPAQUE reprocessing case, this * doesn't matter, as long as the final reprocessed image has the best quality. * 2. Application may modify the YUV output buffer data. For example, for image fusion use * case, where multiple output images are merged together to improve the signal-to-noise * ratio (SNR). The input buffer may be generated from multiple buffers by the application. * To avoid excessive amount of noise reduction and insufficient amount of edge enhancement * being applied to the input buffer, the application can hint the HAL how much effective * exposure time improvement has been done by the application, then the HAL can adjust the * noise reduction and edge enhancement paramters to get best reprocessed image quality. * Below tag can be used for this purpose: * - android.reprocess.effectiveExposureFactor * The value would be exposure time increase factor applied to the original output image, * for example, if there are N image merged, the exposure time increase factor would be up * to sqrt(N). See this tag spec for more details. * * S10.3 Reprocessing pipeline characteristics * * Reprocessing pipeline has below different characteristics comparing with normal output * pipeline: * * 1. The reprocessing result can be returned ahead of the pending normal output results. But * the FIFO ordering must be maintained for all reprocessing results. For example, there are * below requests (A stands for output requests, B stands for reprocessing requests) * being processed by the HAL: * A1, A2, A3, A4, B1, A5, B2, A6... * result of B1 can be returned before A1-A4, but result of B2 must be returned after B1. * 2. Single input rule: For a given reprocessing request, all output buffers must be from the * input buffer, rather than sensor output. For example, if a reprocess request include both * JPEG and preview buffers, all output buffers must be produced from the input buffer * included by the reprocessing request, rather than sensor. The HAL must not output preview * buffers from sensor, while output JPEG buffer from the input buffer. * 3. Input buffer will be from camera output directly (ZSL case) or indirectly(image fusion * case). For the case where buffer is modified, the size will remain same. The HAL can * notify CAMERA3_MSG_ERROR_REQUEST if buffer from unknown source is sent. * 4. Result as reprocessing request: The HAL can expect that a reprocessing request is a copy * of one of the output results with minor allowed setting changes. The HAL can notify * CAMERA3_MSG_ERROR_REQUEST if a request from unknown source is issued. * 5. Output buffers may not be used as inputs across the configure stream boundary, This is * because an opaque stream like the ZSL output stream may have different actual image size * inside of the ZSL buffer to save power and bandwidth for smaller resolution JPEG capture. * The HAL may notify CAMERA3_MSG_ERROR_REQUEST if this case occurs. * 6. HAL Reprocess requests error reporting during flush should follow the same rule specified * by flush() method. * */ __BEGIN_DECLS struct camera3_device; /********************************************************************** * * Camera3 stream and stream buffer definitions. * * These structs and enums define the handles and contents of the input and * output streams connecting the HAL to various framework and application buffer * consumers. Each stream is backed by a gralloc buffer queue. * */ /** * camera3_stream_type_t: * * The type of the camera stream, which defines whether the camera HAL device is * the producer or the consumer for that stream, and how the buffers of the * stream relate to the other streams. */ typedef enum camera3_stream_type { /** * This stream is an output stream; the camera HAL device will be * responsible for filling buffers from this stream with newly captured or * reprocessed image data. */ CAMERA3_STREAM_OUTPUT = 0, /** * This stream is an input stream; the camera HAL device will be responsible * for reading buffers from this stream and sending them through the camera * processing pipeline, as if the buffer was a newly captured image from the * imager. * * The pixel format for input stream can be any format reported by * android.scaler.availableInputOutputFormatsMap. The pixel format of the * output stream that is used to produce the reprocessing data may be any * format reported by android.scaler.availableStreamConfigurations. The * supported input/output stream combinations depends the camera device * capabilities, see android.scaler.availableInputOutputFormatsMap for * stream map details. * * This kind of stream is generally used to reprocess data into higher * quality images (that otherwise would cause a frame rate performance * loss), or to do off-line reprocessing. * * CAMERA_DEVICE_API_VERSION_3_3: * The typical use cases are OPAQUE (typically ZSL) and YUV reprocessing, * see S8.2, S8.3 and S10 for more details. */ CAMERA3_STREAM_INPUT = 1, /** * This stream can be used for input and output. Typically, the stream is * used as an output stream, but occasionally one already-filled buffer may * be sent back to the HAL device for reprocessing. * * This kind of stream is meant generally for Zero Shutter Lag (ZSL) * features, where copying the captured image from the output buffer to the * reprocessing input buffer would be expensive. See S8.1 for more details. * * Note that the HAL will always be reprocessing data it produced. * */ CAMERA3_STREAM_BIDIRECTIONAL = 2, /** * Total number of framework-defined stream types */ CAMERA3_NUM_STREAM_TYPES } camera3_stream_type_t; /** * camera3_stream_rotation_t: * * The required counterclockwise rotation of camera stream. */ typedef enum camera3_stream_rotation { /* No rotation */ CAMERA3_STREAM_ROTATION_0 = 0, /* Rotate by 90 degree counterclockwise */ CAMERA3_STREAM_ROTATION_90 = 1, /* Rotate by 180 degree counterclockwise */ CAMERA3_STREAM_ROTATION_180 = 2, /* Rotate by 270 degree counterclockwise */ CAMERA3_STREAM_ROTATION_270 = 3 } camera3_stream_rotation_t; /** * camera3_stream_configuration_mode_t: * * This defines the general operation mode for the HAL (for a given stream configuration), where * modes besides NORMAL have different semantics, and usually limit the generality of the API in * exchange for higher performance in some particular area. */ typedef enum camera3_stream_configuration_mode { /** * Normal stream configuration operation mode. This is the default camera operation mode, * where all semantics of HAL APIs and metadata controls apply. */ CAMERA3_STREAM_CONFIGURATION_NORMAL_MODE = 0, /** * Special constrained high speed operation mode for devices that can not support high * speed output in NORMAL mode. All streams in this configuration are operating at high speed * mode and have different characteristics and limitations to achieve high speed output. * The NORMAL mode can still be used for high speed output if the HAL can support high speed * output while satisfying all the semantics of HAL APIs and metadata controls. It is * recommended for the HAL to support high speed output in NORMAL mode (by advertising the high * speed FPS ranges in android.control.aeAvailableTargetFpsRanges) if possible. * * This mode has below limitations/requirements: * * 1. The HAL must support up to 2 streams with sizes reported by * android.control.availableHighSpeedVideoConfigurations. * 2. In this mode, the HAL is expected to output up to 120fps or higher. This mode must * support the targeted FPS range and size configurations reported by * android.control.availableHighSpeedVideoConfigurations. * 3. The HAL must support HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED output stream format. * 4. To achieve efficient high speed streaming, the HAL may have to aggregate * multiple frames together and send to camera device for processing where the request * controls are same for all the frames in this batch (batch mode). The HAL must support * max batch size and the max batch size requirements defined by * android.control.availableHighSpeedVideoConfigurations. * 5. In this mode, the HAL must override aeMode, awbMode, and afMode to ON, ON, and * CONTINUOUS_VIDEO, respectively. All post-processing block mode controls must be * overridden to be FAST. Therefore, no manual control of capture and post-processing * parameters is possible. All other controls operate the same as when * android.control.mode == AUTO. This means that all other android.control.* fields * must continue to work, such as * * android.control.aeTargetFpsRange * android.control.aeExposureCompensation * android.control.aeLock * android.control.awbLock * android.control.effectMode * android.control.aeRegions * android.control.afRegions * android.control.awbRegions * android.control.afTrigger * android.control.aePrecaptureTrigger * * Outside of android.control.*, the following controls must work: * * android.flash.mode (TORCH mode only, automatic flash for still capture will not work * since aeMode is ON) * android.lens.opticalStabilizationMode (if it is supported) * android.scaler.cropRegion * android.statistics.faceDetectMode (if it is supported) * 6. To reduce the amount of data passed across process boundaries at * high frame rate, within one batch, camera framework only propagates * the last shutter notify and the last capture results (including partial * results and final result) to the app. The shutter notifies and capture * results for the other requests in the batch are derived by * the camera framework. As a result, the HAL can return empty metadata * except for the last result in the batch. * * For more details about high speed stream requirements, see * android.control.availableHighSpeedVideoConfigurations and CONSTRAINED_HIGH_SPEED_VIDEO * capability defined in android.request.availableCapabilities. * * This mode only needs to be supported by HALs that include CONSTRAINED_HIGH_SPEED_VIDEO in * the android.request.availableCapabilities static metadata. */ CAMERA3_STREAM_CONFIGURATION_CONSTRAINED_HIGH_SPEED_MODE = 1, /** * First value for vendor-defined stream configuration modes. */ CAMERA3_VENDOR_STREAM_CONFIGURATION_MODE_START = 0x8000 } camera3_stream_configuration_mode_t; /** * camera3_stream_t: * * A handle to a single camera input or output stream. A stream is defined by * the framework by its buffer resolution and format, and additionally by the * HAL with the gralloc usage flags and the maximum in-flight buffer count. * * The stream structures are owned by the framework, but pointers to a * camera3_stream passed into the HAL by configure_streams() are valid until the * end of the first subsequent configure_streams() call that _does not_ include * that camera3_stream as an argument, or until the end of the close() call. * * All camera3_stream framework-controlled members are immutable once the * camera3_stream is passed into configure_streams(). The HAL may only change * the HAL-controlled parameters during a configure_streams() call, except for * the contents of the private pointer. * * If a configure_streams() call returns a non-fatal error, all active streams * remain valid as if configure_streams() had not been called. * * The endpoint of the stream is not visible to the camera HAL device. * In DEVICE_API_VERSION_3_1, this was changed to share consumer usage flags * on streams where the camera is a producer (OUTPUT and BIDIRECTIONAL stream * types) see the usage field below. */ typedef struct camera3_stream { /***** * Set by framework before configure_streams() */ /** * The type of the stream, one of the camera3_stream_type_t values. */ int stream_type; /** * The width in pixels of the buffers in this stream */ uint32_t width; /** * The height in pixels of the buffers in this stream */ uint32_t height; /** * The pixel format for the buffers in this stream. Format is a value from * the HAL_PIXEL_FORMAT_* list in system/core/include/system/graphics.h, or * from device-specific headers. * * If HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED is used, then the platform * gralloc module will select a format based on the usage flags provided by * the camera device and the other endpoint of the stream. * * <= CAMERA_DEVICE_API_VERSION_3_1: * * The camera HAL device must inspect the buffers handed to it in the * subsequent register_stream_buffers() call to obtain the * implementation-specific format details, if necessary. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * register_stream_buffers() won't be called by the framework, so the HAL * should configure the ISP and sensor pipeline based purely on the sizes, * usage flags, and formats for the configured streams. */ int format; /***** * Set by HAL during configure_streams(). */ /** * The gralloc usage flags for this stream, as needed by the HAL. The usage * flags are defined in gralloc.h (GRALLOC_USAGE_*), or in device-specific * headers. * * For output streams, these are the HAL's producer usage flags. For input * streams, these are the HAL's consumer usage flags. The usage flags from * the producer and the consumer will be combined together and then passed * to the platform gralloc HAL module for allocating the gralloc buffers for * each stream. * * Version information: * * == CAMERA_DEVICE_API_VERSION_3_0: * * No initial value guaranteed when passed via configure_streams(). * HAL may not use this field as input, and must write over this field * with its usage flags. * * >= CAMERA_DEVICE_API_VERSION_3_1: * * For stream_type OUTPUT and BIDIRECTIONAL, when passed via * configure_streams(), the initial value of this is the consumer's * usage flags. The HAL may use these consumer flags to decide stream * configuration. * For stream_type INPUT, when passed via configure_streams(), the initial * value of this is 0. * For all streams passed via configure_streams(), the HAL must write * over this field with its usage flags. * * From Android O, the usage flag for an output stream may be bitwise * combination of usage flags for multiple consumers, for the purpose of * sharing one camera stream between those consumers. The HAL must fail * configure_streams call with -EINVAL if the combined flags cannot be * supported due to imcompatible buffer format, dataSpace, or other hardware * limitations. */ uint32_t usage; /** * The maximum number of buffers the HAL device may need to have dequeued at * the same time. The HAL device may not have more buffers in-flight from * this stream than this value. */ uint32_t max_buffers; /** * A handle to HAL-private information for the stream. Will not be inspected * by the framework code. */ void *priv; /** * A field that describes the contents of the buffer. The format and buffer * dimensions define the memory layout and structure of the stream buffers, * while dataSpace defines the meaning of the data within the buffer. * * For most formats, dataSpace defines the color space of the image data. * In addition, for some formats, dataSpace indicates whether image- or * depth-based data is requested. See system/core/include/system/graphics.h * for details of formats and valid dataSpace values for each format. * * Version information: * * < CAMERA_DEVICE_API_VERSION_3_3: * * Not defined and should not be accessed. dataSpace should be assumed to * be HAL_DATASPACE_UNKNOWN, and the appropriate color space, etc, should * be determined from the usage flags and the format. * * = CAMERA_DEVICE_API_VERSION_3_3: * * Always set by the camera service. HAL must use this dataSpace to * configure the stream to the correct colorspace, or to select between * color and depth outputs if supported. The dataspace values are the * legacy definitions in graphics.h * * >= CAMERA_DEVICE_API_VERSION_3_4: * * Always set by the camera service. HAL must use this dataSpace to * configure the stream to the correct colorspace, or to select between * color and depth outputs if supported. The dataspace values are set * using the V0 dataspace definitions in graphics.h */ android_dataspace_t data_space; /** * The required output rotation of the stream, one of * the camera3_stream_rotation_t values. This must be inspected by HAL along * with stream width and height. For example, if the rotation is 90 degree * and the stream width and height is 720 and 1280 respectively, camera service * will supply buffers of size 720x1280, and HAL should capture a 1280x720 image * and rotate the image by 90 degree counterclockwise. The rotation field is * no-op when the stream type is input. Camera HAL must ignore the rotation * field for an input stream. * * <= CAMERA_DEVICE_API_VERSION_3_2: * * Not defined and must not be accessed. HAL must not apply any rotation * on output images. * * >= CAMERA_DEVICE_API_VERSION_3_3: * * Always set by camera service. HAL must inspect this field during stream * configuration and returns -EINVAL if HAL cannot perform such rotation. * HAL must always support CAMERA3_STREAM_ROTATION_0, so a * configure_streams() call must not fail for unsupported rotation if * rotation field of all streams is CAMERA3_STREAM_ROTATION_0. * */ int rotation; /* reserved for future use */ void *reserved[7]; } camera3_stream_t; /** * camera3_stream_configuration_t: * * A structure of stream definitions, used by configure_streams(). This * structure defines all the output streams and the reprocessing input * stream for the current camera use case. */ typedef struct camera3_stream_configuration { /** * The total number of streams requested by the framework. This includes * both input and output streams. The number of streams will be at least 1, * and there will be at least one output-capable stream. */ uint32_t num_streams; /** * An array of camera stream pointers, defining the input/output * configuration for the camera HAL device. * * At most one input-capable stream may be defined (INPUT or BIDIRECTIONAL) * in a single configuration. * * At least one output-capable stream must be defined (OUTPUT or * BIDIRECTIONAL). */ camera3_stream_t **streams; /** * >= CAMERA_DEVICE_API_VERSION_3_3: * * The operation mode of streams in this configuration, one of the value * defined in camera3_stream_configuration_mode_t. The HAL can use this * mode as an indicator to set the stream property (e.g., * camera3_stream->max_buffers) appropriately. For example, if the * configuration is * CAMERA3_STREAM_CONFIGURATION_CONSTRAINED_HIGH_SPEED_MODE, the HAL may * want to set aside more buffers for batch mode operation (see * android.control.availableHighSpeedVideoConfigurations for batch mode * definition). * */ uint32_t operation_mode; } camera3_stream_configuration_t; /** * camera3_buffer_status_t: * * The current status of a single stream buffer. */ typedef enum camera3_buffer_status { /** * The buffer is in a normal state, and can be used after waiting on its * sync fence. */ CAMERA3_BUFFER_STATUS_OK = 0, /** * The buffer does not contain valid data, and the data in it should not be * used. The sync fence must still be waited on before reusing the buffer. */ CAMERA3_BUFFER_STATUS_ERROR = 1 } camera3_buffer_status_t; /** * camera3_stream_buffer_t: * * A single buffer from a camera3 stream. It includes a handle to its parent * stream, the handle to the gralloc buffer itself, and sync fences * * The buffer does not specify whether it is to be used for input or output; * that is determined by its parent stream type and how the buffer is passed to * the HAL device. */ typedef struct camera3_stream_buffer { /** * The handle of the stream this buffer is associated with */ camera3_stream_t *stream; /** * The native handle to the buffer */ buffer_handle_t *buffer; /** * Current state of the buffer, one of the camera3_buffer_status_t * values. The framework will not pass buffers to the HAL that are in an * error state. In case a buffer could not be filled by the HAL, it must * have its status set to CAMERA3_BUFFER_STATUS_ERROR when returned to the * framework with process_capture_result(). */ int status; /** * The acquire sync fence for this buffer. The HAL must wait on this fence * fd before attempting to read from or write to this buffer. * * The framework may be set to -1 to indicate that no waiting is necessary * for this buffer. * * When the HAL returns an output buffer to the framework with * process_capture_result(), the acquire_fence must be set to -1. If the HAL * never waits on the acquire_fence due to an error in filling a buffer, * when calling process_capture_result() the HAL must set the release_fence * of the buffer to be the acquire_fence passed to it by the framework. This * will allow the framework to wait on the fence before reusing the buffer. * * For input buffers, the HAL must not change the acquire_fence field during * the process_capture_request() call. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * When the HAL returns an input buffer to the framework with * process_capture_result(), the acquire_fence must be set to -1. If the HAL * never waits on input buffer acquire fence due to an error, the sync * fences should be handled similarly to the way they are handled for output * buffers. */ int acquire_fence; /** * The release sync fence for this buffer. The HAL must set this fence when * returning buffers to the framework, or write -1 to indicate that no * waiting is required for this buffer. * * For the output buffers, the fences must be set in the output_buffers * array passed to process_capture_result(). * * <= CAMERA_DEVICE_API_VERSION_3_1: * * For the input buffer, the release fence must be set by the * process_capture_request() call. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * For the input buffer, the fences must be set in the input_buffer * passed to process_capture_result(). * * After signaling the release_fence for this buffer, the HAL * should not make any further attempts to access this buffer as the * ownership has been fully transferred back to the framework. * * If a fence of -1 was specified then the ownership of this buffer * is transferred back immediately upon the call of process_capture_result. */ int release_fence; } camera3_stream_buffer_t; /** * camera3_stream_buffer_set_t: * * The complete set of gralloc buffers for a stream. This structure is given to * register_stream_buffers() to allow the camera HAL device to register/map/etc * newly allocated stream buffers. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * Deprecated (and not used). In particular, * register_stream_buffers is also deprecated and will never be invoked. * */ typedef struct camera3_stream_buffer_set { /** * The stream handle for the stream these buffers belong to */ camera3_stream_t *stream; /** * The number of buffers in this stream. It is guaranteed to be at least * stream->max_buffers. */ uint32_t num_buffers; /** * The array of gralloc buffer handles for this stream. If the stream format * is set to HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED, the camera HAL device * should inspect the passed-in buffers to determine any platform-private * pixel format information. */ buffer_handle_t **buffers; } camera3_stream_buffer_set_t; /** * camera3_jpeg_blob: * * Transport header for compressed JPEG buffers in output streams. * * To capture JPEG images, a stream is created using the pixel format * HAL_PIXEL_FORMAT_BLOB. The buffer size for the stream is calculated by the * framework, based on the static metadata field android.jpeg.maxSize. Since * compressed JPEG images are of variable size, the HAL needs to include the * final size of the compressed image using this structure inside the output * stream buffer. The JPEG blob ID field must be set to CAMERA3_JPEG_BLOB_ID. * * Transport header should be at the end of the JPEG output stream buffer. That * means the jpeg_blob_id must start at byte[buffer_size - * sizeof(camera3_jpeg_blob)], where the buffer_size is the size of gralloc buffer. * Any HAL using this transport header must account for it in android.jpeg.maxSize * The JPEG data itself starts at the beginning of the buffer and should be * jpeg_size bytes long. */ typedef struct camera3_jpeg_blob { uint16_t jpeg_blob_id; uint32_t jpeg_size; } camera3_jpeg_blob_t; enum { CAMERA3_JPEG_BLOB_ID = 0x00FF }; /********************************************************************** * * Message definitions for the HAL notify() callback. * * These definitions are used for the HAL notify callback, to signal * asynchronous events from the HAL device to the Android framework. * */ /** * camera3_msg_type: * * Indicates the type of message sent, which specifies which member of the * message union is valid. * */ typedef enum camera3_msg_type { /** * An error has occurred. camera3_notify_msg.message.error contains the * error information. */ CAMERA3_MSG_ERROR = 1, /** * The exposure of a given request or processing a reprocess request has * begun. camera3_notify_msg.message.shutter contains the information * the capture. */ CAMERA3_MSG_SHUTTER = 2, /** * Number of framework message types */ CAMERA3_NUM_MESSAGES } camera3_msg_type_t; /** * Defined error codes for CAMERA_MSG_ERROR */ typedef enum camera3_error_msg_code { /** * A serious failure occured. No further frames or buffer streams will * be produced by the device. Device should be treated as closed. The * client must reopen the device to use it again. The frame_number field * is unused. */ CAMERA3_MSG_ERROR_DEVICE = 1, /** * An error has occurred in processing a request. No output (metadata or * buffers) will be produced for this request. The frame_number field * specifies which request has been dropped. Subsequent requests are * unaffected, and the device remains operational. */ CAMERA3_MSG_ERROR_REQUEST = 2, /** * An error has occurred in producing an output result metadata buffer * for a request, but output stream buffers for it will still be * available. Subsequent requests are unaffected, and the device remains * operational. The frame_number field specifies the request for which * result metadata won't be available. */ CAMERA3_MSG_ERROR_RESULT = 3, /** * An error has occurred in placing an output buffer into a stream for a * request. The frame metadata and other buffers may still be * available. Subsequent requests are unaffected, and the device remains * operational. The frame_number field specifies the request for which the * buffer was dropped, and error_stream contains a pointer to the stream * that dropped the frame. */ CAMERA3_MSG_ERROR_BUFFER = 4, /** * Number of error types */ CAMERA3_MSG_NUM_ERRORS } camera3_error_msg_code_t; /** * camera3_error_msg_t: * * Message contents for CAMERA3_MSG_ERROR */ typedef struct camera3_error_msg { /** * Frame number of the request the error applies to. 0 if the frame number * isn't applicable to the error. */ uint32_t frame_number; /** * Pointer to the stream that had a failure. NULL if the stream isn't * applicable to the error. */ camera3_stream_t *error_stream; /** * The code for this error; one of the CAMERA_MSG_ERROR enum values. */ int error_code; } camera3_error_msg_t; /** * camera3_shutter_msg_t: * * Message contents for CAMERA3_MSG_SHUTTER */ typedef struct camera3_shutter_msg { /** * Frame number of the request that has begun exposure or reprocessing. */ uint32_t frame_number; /** * Timestamp for the start of capture. For a reprocess request, this must * be input image's start of capture. This must match the capture result * metadata's sensor exposure start timestamp. */ uint64_t timestamp; } camera3_shutter_msg_t; /** * camera3_notify_msg_t: * * The message structure sent to camera3_callback_ops_t.notify() */ typedef struct camera3_notify_msg { /** * The message type. One of camera3_notify_msg_type, or a private extension. */ int type; union { /** * Error message contents. Valid if type is CAMERA3_MSG_ERROR */ camera3_error_msg_t error; /** * Shutter message contents. Valid if type is CAMERA3_MSG_SHUTTER */ camera3_shutter_msg_t shutter; /** * Generic message contents. Used to ensure a minimum size for custom * message types. */ uint8_t generic[32]; } message; } camera3_notify_msg_t; /********************************************************************** * * Capture request/result definitions for the HAL process_capture_request() * method, and the process_capture_result() callback. * */ /** * camera3_request_template_t: * * Available template types for * camera3_device_ops.construct_default_request_settings() */ typedef enum camera3_request_template { /** * Standard camera preview operation with 3A on auto. */ CAMERA3_TEMPLATE_PREVIEW = 1, /** * Standard camera high-quality still capture with 3A and flash on auto. */ CAMERA3_TEMPLATE_STILL_CAPTURE = 2, /** * Standard video recording plus preview with 3A on auto, torch off. */ CAMERA3_TEMPLATE_VIDEO_RECORD = 3, /** * High-quality still capture while recording video. Application will * include preview, video record, and full-resolution YUV or JPEG streams in * request. Must not cause stuttering on video stream. 3A on auto. */ CAMERA3_TEMPLATE_VIDEO_SNAPSHOT = 4, /** * Zero-shutter-lag mode. Application will request preview and * full-resolution data for each frame, and reprocess it to JPEG when a * still image is requested by user. Settings should provide highest-quality * full-resolution images without compromising preview frame rate. 3A on * auto. */ CAMERA3_TEMPLATE_ZERO_SHUTTER_LAG = 5, /** * A basic template for direct application control of capture * parameters. All automatic control is disabled (auto-exposure, auto-white * balance, auto-focus), and post-processing parameters are set to preview * quality. The manual capture parameters (exposure, sensitivity, etc.) * are set to reasonable defaults, but should be overridden by the * application depending on the intended use case. */ CAMERA3_TEMPLATE_MANUAL = 6, /* Total number of templates */ CAMERA3_TEMPLATE_COUNT, /** * First value for vendor-defined request templates */ CAMERA3_VENDOR_TEMPLATE_START = 0x40000000 } camera3_request_template_t; /** * camera3_capture_request_t: * * A single request for image capture/buffer reprocessing, sent to the Camera * HAL device by the framework in process_capture_request(). * * The request contains the settings to be used for this capture, and the set of * output buffers to write the resulting image data in. It may optionally * contain an input buffer, in which case the request is for reprocessing that * input buffer instead of capturing a new image with the camera sensor. The * capture is identified by the frame_number. * * In response, the camera HAL device must send a camera3_capture_result * structure asynchronously to the framework, using the process_capture_result() * callback. */ typedef struct camera3_capture_request { /** * The frame number is an incrementing integer set by the framework to * uniquely identify this capture. It needs to be returned in the result * call, and is also used to identify the request in asynchronous * notifications sent to camera3_callback_ops_t.notify(). */ uint32_t frame_number; /** * The settings buffer contains the capture and processing parameters for * the request. As a special case, a NULL settings buffer indicates that the * settings are identical to the most-recently submitted capture request. A * NULL buffer cannot be used as the first submitted request after a * configure_streams() call. */ const camera_metadata_t *settings; /** * The input stream buffer to use for this request, if any. * * If input_buffer is NULL, then the request is for a new capture from the * imager. If input_buffer is valid, the request is for reprocessing the * image contained in input_buffer. * * In the latter case, the HAL must set the release_fence of the * input_buffer to a valid sync fence, or to -1 if the HAL does not support * sync, before process_capture_request() returns. * * The HAL is required to wait on the acquire sync fence of the input buffer * before accessing it. * * <= CAMERA_DEVICE_API_VERSION_3_1: * * Any input buffer included here will have been registered with the HAL * through register_stream_buffers() before its inclusion in a request. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * The buffers will not have been pre-registered with the HAL. * Subsequent requests may reuse buffers, or provide entirely new buffers. */ camera3_stream_buffer_t *input_buffer; /** * The number of output buffers for this capture request. Must be at least * 1. */ uint32_t num_output_buffers; /** * An array of num_output_buffers stream buffers, to be filled with image * data from this capture/reprocess. The HAL must wait on the acquire fences * of each stream buffer before writing to them. * * The HAL takes ownership of the actual buffer_handle_t entries in * output_buffers; the framework does not access them until they are * returned in a camera3_capture_result_t. * * <= CAMERA_DEVICE_API_VERSION_3_1: * * All the buffers included here will have been registered with the HAL * through register_stream_buffers() before their inclusion in a request. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * Any or all of the buffers included here may be brand new in this * request (having never before seen by the HAL). */ const camera3_stream_buffer_t *output_buffers; } camera3_capture_request_t; /** * camera3_capture_result_t: * * The result of a single capture/reprocess by the camera HAL device. This is * sent to the framework asynchronously with process_capture_result(), in * response to a single capture request sent to the HAL with * process_capture_request(). Multiple process_capture_result() calls may be * performed by the HAL for each request. * * Each call, all with the same frame * number, may contain some subset of the output buffers, and/or the result * metadata. The metadata may only be provided once for a given frame number; * all other calls must set the result metadata to NULL. * * The result structure contains the output metadata from this capture, and the * set of output buffers that have been/will be filled for this capture. Each * output buffer may come with a release sync fence that the framework will wait * on before reading, in case the buffer has not yet been filled by the HAL. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * The metadata may be provided multiple times for a single frame number. The * framework will accumulate together the final result set by combining each * partial result together into the total result set. * * If an input buffer is given in a request, the HAL must return it in one of * the process_capture_result calls, and the call may be to just return the input * buffer, without metadata and output buffers; the sync fences must be handled * the same way they are done for output buffers. * * * Performance considerations: * * Applications will also receive these partial results immediately, so sending * partial results is a highly recommended performance optimization to avoid * the total pipeline latency before sending the results for what is known very * early on in the pipeline. * * A typical use case might be calculating the AF state halfway through the * pipeline; by sending the state back to the framework immediately, we get a * 50% performance increase and perceived responsiveness of the auto-focus. * */ typedef struct camera3_capture_result { /** * The frame number is an incrementing integer set by the framework in the * submitted request to uniquely identify this capture. It is also used to * identify the request in asynchronous notifications sent to * camera3_callback_ops_t.notify(). */ uint32_t frame_number; /** * The result metadata for this capture. This contains information about the * final capture parameters, the state of the capture and post-processing * hardware, the state of the 3A algorithms, if enabled, and the output of * any enabled statistics units. * * Only one call to process_capture_result() with a given frame_number may * include the result metadata. All other calls for the same frame_number * must set this to NULL. * * If there was an error producing the result metadata, result must be an * empty metadata buffer, and notify() must be called with ERROR_RESULT. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * Multiple calls to process_capture_result() with a given frame_number * may include the result metadata. * * Partial metadata submitted should not include any metadata key returned * in a previous partial result for a given frame. Each new partial result * for that frame must also set a distinct partial_result value. * * If notify has been called with ERROR_RESULT, all further partial * results for that frame are ignored by the framework. */ const camera_metadata_t *result; /** * The number of output buffers returned in this result structure. Must be * less than or equal to the matching capture request's count. If this is * less than the buffer count in the capture request, at least one more call * to process_capture_result with the same frame_number must be made, to * return the remaining output buffers to the framework. This may only be * zero if the structure includes valid result metadata or an input buffer * is returned in this result. */ uint32_t num_output_buffers; /** * The handles for the output stream buffers for this capture. They may not * yet be filled at the time the HAL calls process_capture_result(); the * framework will wait on the release sync fences provided by the HAL before * reading the buffers. * * The HAL must set the stream buffer's release sync fence to a valid sync * fd, or to -1 if the buffer has already been filled. * * If the HAL encounters an error while processing the buffer, and the * buffer is not filled, the buffer's status field must be set to * CAMERA3_BUFFER_STATUS_ERROR. If the HAL did not wait on the acquire fence * before encountering the error, the acquire fence should be copied into * the release fence, to allow the framework to wait on the fence before * reusing the buffer. * * The acquire fence must be set to -1 for all output buffers. If * num_output_buffers is zero, this may be NULL. In that case, at least one * more process_capture_result call must be made by the HAL to provide the * output buffers. * * When process_capture_result is called with a new buffer for a frame, * all previous frames' buffers for that corresponding stream must have been * already delivered (the fences need not have yet been signaled). * * >= CAMERA_DEVICE_API_VERSION_3_2: * * Gralloc buffers for a frame may be sent to framework before the * corresponding SHUTTER-notify. * * Performance considerations: * * Buffers delivered to the framework will not be dispatched to the * application layer until a start of exposure timestamp has been received * via a SHUTTER notify() call. It is highly recommended to * dispatch that call as early as possible. */ const camera3_stream_buffer_t *output_buffers; /** * >= CAMERA_DEVICE_API_VERSION_3_2: * * The handle for the input stream buffer for this capture. It may not * yet be consumed at the time the HAL calls process_capture_result(); the * framework will wait on the release sync fences provided by the HAL before * reusing the buffer. * * The HAL should handle the sync fences the same way they are done for * output_buffers. * * Only one input buffer is allowed to be sent per request. Similarly to * output buffers, the ordering of returned input buffers must be * maintained by the HAL. * * Performance considerations: * * The input buffer should be returned as early as possible. If the HAL * supports sync fences, it can call process_capture_result to hand it back * with sync fences being set appropriately. If the sync fences are not * supported, the buffer can only be returned when it is consumed, which * may take long time; the HAL may choose to copy this input buffer to make * the buffer return sooner. */ const camera3_stream_buffer_t *input_buffer; /** * >= CAMERA_DEVICE_API_VERSION_3_2: * * In order to take advantage of partial results, the HAL must set the * static metadata android.request.partialResultCount to the number of * partial results it will send for each frame. * * Each new capture result with a partial result must set * this field (partial_result) to a distinct inclusive value between * 1 and android.request.partialResultCount. * * HALs not wishing to take advantage of this feature must not * set an android.request.partialResultCount or partial_result to a value * other than 1. * * This value must be set to 0 when a capture result contains buffers only * and no metadata. */ uint32_t partial_result; } camera3_capture_result_t; /********************************************************************** * * Callback methods for the HAL to call into the framework. * * These methods are used to return metadata and image buffers for a completed * or failed captures, and to notify the framework of asynchronous events such * as errors. * * The framework will not call back into the HAL from within these callbacks, * and these calls will not block for extended periods. * */ typedef struct camera3_callback_ops { /** * process_capture_result: * * Send results from a completed capture to the framework. * process_capture_result() may be invoked multiple times by the HAL in * response to a single capture request. This allows, for example, the * metadata and low-resolution buffers to be returned in one call, and * post-processed JPEG buffers in a later call, once it is available. Each * call must include the frame number of the request it is returning * metadata or buffers for. * * A component (buffer or metadata) of the complete result may only be * included in one process_capture_result call. A buffer for each stream, * and the result metadata, must be returned by the HAL for each request in * one of the process_capture_result calls, even in case of errors producing * some of the output. A call to process_capture_result() with neither * output buffers or result metadata is not allowed. * * The order of returning metadata and buffers for a single result does not * matter, but buffers for a given stream must be returned in FIFO order. So * the buffer for request 5 for stream A must always be returned before the * buffer for request 6 for stream A. This also applies to the result * metadata; the metadata for request 5 must be returned before the metadata * for request 6. * * However, different streams are independent of each other, so it is * acceptable and expected that the buffer for request 5 for stream A may be * returned after the buffer for request 6 for stream B is. And it is * acceptable that the result metadata for request 6 for stream B is * returned before the buffer for request 5 for stream A is. * * The HAL retains ownership of result structure, which only needs to be * valid to access during this call. The framework will copy whatever it * needs before this call returns. * * The output buffers do not need to be filled yet; the framework will wait * on the stream buffer release sync fence before reading the buffer * data. Therefore, this method should be called by the HAL as soon as * possible, even if some or all of the output buffers are still in * being filled. The HAL must include valid release sync fences into each * output_buffers stream buffer entry, or -1 if that stream buffer is * already filled. * * If the result buffer cannot be constructed for a request, the HAL should * return an empty metadata buffer, but still provide the output buffers and * their sync fences. In addition, notify() must be called with an * ERROR_RESULT message. * * If an output buffer cannot be filled, its status field must be set to * STATUS_ERROR. In addition, notify() must be called with a ERROR_BUFFER * message. * * If the entire capture has failed, then this method still needs to be * called to return the output buffers to the framework. All the buffer * statuses should be STATUS_ERROR, and the result metadata should be an * empty buffer. In addition, notify() must be called with a ERROR_REQUEST * message. In this case, individual ERROR_RESULT/ERROR_BUFFER messages * should not be sent. * * Performance requirements: * * This is a non-blocking call. The framework will return this call in 5ms. * * The pipeline latency (see S7 for definition) should be less than or equal to * 4 frame intervals, and must be less than or equal to 8 frame intervals. * */ void (*process_capture_result)(const struct camera3_callback_ops *, const camera3_capture_result_t *result); /** * notify: * * Asynchronous notification callback from the HAL, fired for various * reasons. Only for information independent of frame capture, or that * require specific timing. The ownership of the message structure remains * with the HAL, and the msg only needs to be valid for the duration of this * call. * * Multiple threads may call notify() simultaneously. * * <= CAMERA_DEVICE_API_VERSION_3_1: * * The notification for the start of exposure for a given request must be * sent by the HAL before the first call to process_capture_result() for * that request is made. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * Buffers delivered to the framework will not be dispatched to the * application layer until a start of exposure timestamp (or input image's * start of exposure timestamp for a reprocess request) has been received * via a SHUTTER notify() call. It is highly recommended to dispatch this * call as early as possible. * * ------------------------------------------------------------------------ * Performance requirements: * * This is a non-blocking call. The framework will return this call in 5ms. */ void (*notify)(const struct camera3_callback_ops *, const camera3_notify_msg_t *msg); } camera3_callback_ops_t; /********************************************************************** * * Camera device operations * */ typedef struct camera3_device_ops { /** * initialize: * * One-time initialization to pass framework callback function pointers to * the HAL. Will be called once after a successful open() call, before any * other functions are called on the camera3_device_ops structure. * * Performance requirements: * * This should be a non-blocking call. The HAL should return from this call * in 5ms, and must return from this call in 10ms. * * Return values: * * 0: On successful initialization * * -ENODEV: If initialization fails. Only close() can be called successfully * by the framework after this. */ int (*initialize)(const struct camera3_device *, const camera3_callback_ops_t *callback_ops); /********************************************************************** * Stream management */ /** * configure_streams: * * CAMERA_DEVICE_API_VERSION_3_0 only: * * Reset the HAL camera device processing pipeline and set up new input and * output streams. This call replaces any existing stream configuration with * the streams defined in the stream_list. This method will be called at * least once after initialize() before a request is submitted with * process_capture_request(). * * The stream_list must contain at least one output-capable stream, and may * not contain more than one input-capable stream. * * The stream_list may contain streams that are also in the currently-active * set of streams (from the previous call to configure_stream()). These * streams will already have valid values for usage, max_buffers, and the * private pointer. * * If such a stream has already had its buffers registered, * register_stream_buffers() will not be called again for the stream, and * buffers from the stream can be immediately included in input requests. * * If the HAL needs to change the stream configuration for an existing * stream due to the new configuration, it may rewrite the values of usage * and/or max_buffers during the configure call. * * The framework will detect such a change, and will then reallocate the * stream buffers, and call register_stream_buffers() again before using * buffers from that stream in a request. * * If a currently-active stream is not included in stream_list, the HAL may * safely remove any references to that stream. It will not be reused in a * later configure() call by the framework, and all the gralloc buffers for * it will be freed after the configure_streams() call returns. * * The stream_list structure is owned by the framework, and may not be * accessed once this call completes. The address of an individual * camera3_stream_t structure will remain valid for access by the HAL until * the end of the first configure_stream() call which no longer includes * that camera3_stream_t in the stream_list argument. The HAL may not change * values in the stream structure outside of the private pointer, except for * the usage and max_buffers members during the configure_streams() call * itself. * * If the stream is new, the usage, max_buffer, and private pointer fields * of the stream structure will all be set to 0. The HAL device must set * these fields before the configure_streams() call returns. These fields * are then used by the framework and the platform gralloc module to * allocate the gralloc buffers for each stream. * * Before such a new stream can have its buffers included in a capture * request, the framework will call register_stream_buffers() with that * stream. However, the framework is not required to register buffers for * _all_ streams before submitting a request. This allows for quick startup * of (for example) a preview stream, with allocation for other streams * happening later or concurrently. * * ------------------------------------------------------------------------ * CAMERA_DEVICE_API_VERSION_3_1 only: * * Reset the HAL camera device processing pipeline and set up new input and * output streams. This call replaces any existing stream configuration with * the streams defined in the stream_list. This method will be called at * least once after initialize() before a request is submitted with * process_capture_request(). * * The stream_list must contain at least one output-capable stream, and may * not contain more than one input-capable stream. * * The stream_list may contain streams that are also in the currently-active * set of streams (from the previous call to configure_stream()). These * streams will already have valid values for usage, max_buffers, and the * private pointer. * * If such a stream has already had its buffers registered, * register_stream_buffers() will not be called again for the stream, and * buffers from the stream can be immediately included in input requests. * * If the HAL needs to change the stream configuration for an existing * stream due to the new configuration, it may rewrite the values of usage * and/or max_buffers during the configure call. * * The framework will detect such a change, and will then reallocate the * stream buffers, and call register_stream_buffers() again before using * buffers from that stream in a request. * * If a currently-active stream is not included in stream_list, the HAL may * safely remove any references to that stream. It will not be reused in a * later configure() call by the framework, and all the gralloc buffers for * it will be freed after the configure_streams() call returns. * * The stream_list structure is owned by the framework, and may not be * accessed once this call completes. The address of an individual * camera3_stream_t structure will remain valid for access by the HAL until * the end of the first configure_stream() call which no longer includes * that camera3_stream_t in the stream_list argument. The HAL may not change * values in the stream structure outside of the private pointer, except for * the usage and max_buffers members during the configure_streams() call * itself. * * If the stream is new, max_buffer, and private pointer fields of the * stream structure will all be set to 0. The usage will be set to the * consumer usage flags. The HAL device must set these fields before the * configure_streams() call returns. These fields are then used by the * framework and the platform gralloc module to allocate the gralloc * buffers for each stream. * * Before such a new stream can have its buffers included in a capture * request, the framework will call register_stream_buffers() with that * stream. However, the framework is not required to register buffers for * _all_ streams before submitting a request. This allows for quick startup * of (for example) a preview stream, with allocation for other streams * happening later or concurrently. * * ------------------------------------------------------------------------ * >= CAMERA_DEVICE_API_VERSION_3_2: * * Reset the HAL camera device processing pipeline and set up new input and * output streams. This call replaces any existing stream configuration with * the streams defined in the stream_list. This method will be called at * least once after initialize() before a request is submitted with * process_capture_request(). * * The stream_list must contain at least one output-capable stream, and may * not contain more than one input-capable stream. * * The stream_list may contain streams that are also in the currently-active * set of streams (from the previous call to configure_stream()). These * streams will already have valid values for usage, max_buffers, and the * private pointer. * * If the HAL needs to change the stream configuration for an existing * stream due to the new configuration, it may rewrite the values of usage * and/or max_buffers during the configure call. * * The framework will detect such a change, and may then reallocate the * stream buffers before using buffers from that stream in a request. * * If a currently-active stream is not included in stream_list, the HAL may * safely remove any references to that stream. It will not be reused in a * later configure() call by the framework, and all the gralloc buffers for * it will be freed after the configure_streams() call returns. * * The stream_list structure is owned by the framework, and may not be * accessed once this call completes. The address of an individual * camera3_stream_t structure will remain valid for access by the HAL until * the end of the first configure_stream() call which no longer includes * that camera3_stream_t in the stream_list argument. The HAL may not change * values in the stream structure outside of the private pointer, except for * the usage and max_buffers members during the configure_streams() call * itself. * * If the stream is new, max_buffer, and private pointer fields of the * stream structure will all be set to 0. The usage will be set to the * consumer usage flags. The HAL device must set these fields before the * configure_streams() call returns. These fields are then used by the * framework and the platform gralloc module to allocate the gralloc * buffers for each stream. * * Newly allocated buffers may be included in a capture request at any time * by the framework. Once a gralloc buffer is returned to the framework * with process_capture_result (and its respective release_fence has been * signaled) the framework may free or reuse it at any time. * * ------------------------------------------------------------------------ * * Preconditions: * * The framework will only call this method when no captures are being * processed. That is, all results have been returned to the framework, and * all in-flight input and output buffers have been returned and their * release sync fences have been signaled by the HAL. The framework will not * submit new requests for capture while the configure_streams() call is * underway. * * Postconditions: * * The HAL device must configure itself to provide maximum possible output * frame rate given the sizes and formats of the output streams, as * documented in the camera device's static metadata. * * Performance requirements: * * This call is expected to be heavyweight and possibly take several hundred * milliseconds to complete, since it may require resetting and * reconfiguring the image sensor and the camera processing pipeline. * Nevertheless, the HAL device should attempt to minimize the * reconfiguration delay to minimize the user-visible pauses during * application operational mode changes (such as switching from still * capture to video recording). * * The HAL should return from this call in 500ms, and must return from this * call in 1000ms. * * Return values: * * 0: On successful stream configuration * * -EINVAL: If the requested stream configuration is invalid. Some examples * of invalid stream configurations include: * * - Including more than 1 input-capable stream (INPUT or * BIDIRECTIONAL) * * - Not including any output-capable streams (OUTPUT or * BIDIRECTIONAL) * * - Including streams with unsupported formats, or an unsupported * size for that format. * * - Including too many output streams of a certain format. * * - Unsupported rotation configuration (only applies to * devices with version >= CAMERA_DEVICE_API_VERSION_3_3) * * - Stream sizes/formats don't satisfy the * camera3_stream_configuration_t->operation_mode requirements for non-NORMAL mode, * or the requested operation_mode is not supported by the HAL. * (only applies to devices with version >= CAMERA_DEVICE_API_VERSION_3_3) * * Note that the framework submitting an invalid stream * configuration is not normal operation, since stream * configurations are checked before configure. An invalid * configuration means that a bug exists in the framework code, or * there is a mismatch between the HAL's static metadata and the * requirements on streams. * * -ENODEV: If there has been a fatal error and the device is no longer * operational. Only close() can be called successfully by the * framework after this error is returned. */ int (*configure_streams)(const struct camera3_device *, camera3_stream_configuration_t *stream_list); /** * register_stream_buffers: * * >= CAMERA_DEVICE_API_VERSION_3_2: * * DEPRECATED. This will not be called and must be set to NULL. * * <= CAMERA_DEVICE_API_VERSION_3_1: * * Register buffers for a given stream with the HAL device. This method is * called by the framework after a new stream is defined by * configure_streams, and before buffers from that stream are included in a * capture request. If the same stream is listed in a subsequent * configure_streams() call, register_stream_buffers will _not_ be called * again for that stream. * * The framework does not need to register buffers for all configured * streams before it submits the first capture request. This allows quick * startup for preview (or similar use cases) while other streams are still * being allocated. * * This method is intended to allow the HAL device to map or otherwise * prepare the buffers for later use. The buffers passed in will already be * locked for use. At the end of the call, all the buffers must be ready to * be returned to the stream. The buffer_set argument is only valid for the * duration of this call. * * If the stream format was set to HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED, * the camera HAL should inspect the passed-in buffers here to determine any * platform-private pixel format information. * * Performance requirements: * * This should be a non-blocking call. The HAL should return from this call * in 1ms, and must return from this call in 5ms. * * Return values: * * 0: On successful registration of the new stream buffers * * -EINVAL: If the stream_buffer_set does not refer to a valid active * stream, or if the buffers array is invalid. * * -ENOMEM: If there was a failure in registering the buffers. The framework * must consider all the stream buffers to be unregistered, and can * try to register again later. * * -ENODEV: If there is a fatal error, and the device is no longer * operational. Only close() can be called successfully by the * framework after this error is returned. */ int (*register_stream_buffers)(const struct camera3_device *, const camera3_stream_buffer_set_t *buffer_set); /********************************************************************** * Request creation and submission */ /** * construct_default_request_settings: * * Create capture settings for standard camera use cases. * * The device must return a settings buffer that is configured to meet the * requested use case, which must be one of the CAMERA3_TEMPLATE_* * enums. All request control fields must be included. * * The HAL retains ownership of this structure, but the pointer to the * structure must be valid until the device is closed. The framework and the * HAL may not modify the buffer once it is returned by this call. The same * buffer may be returned for subsequent calls for the same template, or for * other templates. * * Performance requirements: * * This should be a non-blocking call. The HAL should return from this call * in 1ms, and must return from this call in 5ms. * * Return values: * * Valid metadata: On successful creation of a default settings * buffer. * * NULL: In case of a fatal error. After this is returned, only * the close() method can be called successfully by the * framework. */ const camera_metadata_t* (*construct_default_request_settings)( const struct camera3_device *, int type); /** * process_capture_request: * * Send a new capture request to the HAL. The HAL should not return from * this call until it is ready to accept the next request to process. Only * one call to process_capture_request() will be made at a time by the * framework, and the calls will all be from the same thread. The next call * to process_capture_request() will be made as soon as a new request and * its associated buffers are available. In a normal preview scenario, this * means the function will be called again by the framework almost * instantly. * * The actual request processing is asynchronous, with the results of * capture being returned by the HAL through the process_capture_result() * call. This call requires the result metadata to be available, but output * buffers may simply provide sync fences to wait on. Multiple requests are * expected to be in flight at once, to maintain full output frame rate. * * The framework retains ownership of the request structure. It is only * guaranteed to be valid during this call. The HAL device must make copies * of the information it needs to retain for the capture processing. The HAL * is responsible for waiting on and closing the buffers' fences and * returning the buffer handles to the framework. * * The HAL must write the file descriptor for the input buffer's release * sync fence into input_buffer->release_fence, if input_buffer is not * NULL. If the HAL returns -1 for the input buffer release sync fence, the * framework is free to immediately reuse the input buffer. Otherwise, the * framework will wait on the sync fence before refilling and reusing the * input buffer. * * >= CAMERA_DEVICE_API_VERSION_3_2: * * The input/output buffers provided by the framework in each request * may be brand new (having never before seen by the HAL). * * ------------------------------------------------------------------------ * Performance considerations: * * Handling a new buffer should be extremely lightweight and there should be * no frame rate degradation or frame jitter introduced. * * This call must return fast enough to ensure that the requested frame * rate can be sustained, especially for streaming cases (post-processing * quality settings set to FAST). The HAL should return this call in 1 * frame interval, and must return from this call in 4 frame intervals. * * Return values: * * 0: On a successful start to processing the capture request * * -EINVAL: If the input is malformed (the settings are NULL when not * allowed, there are 0 output buffers, etc) and capture processing * cannot start. Failures during request processing should be * handled by calling camera3_callback_ops_t.notify(). In case of * this error, the framework will retain responsibility for the * stream buffers' fences and the buffer handles; the HAL should * not close the fences or return these buffers with * process_capture_result. * * -ENODEV: If the camera device has encountered a serious error. After this * error is returned, only the close() method can be successfully * called by the framework. * */ int (*process_capture_request)(const struct camera3_device *, camera3_capture_request_t *request); /********************************************************************** * Miscellaneous methods */ /** * get_metadata_vendor_tag_ops: * * Get methods to query for vendor extension metadata tag information. The * HAL should fill in all the vendor tag operation methods, or leave ops * unchanged if no vendor tags are defined. * * The definition of vendor_tag_query_ops_t can be found in * system/media/camera/include/system/camera_metadata.h. * * >= CAMERA_DEVICE_API_VERSION_3_2: * DEPRECATED. This function has been deprecated and should be set to * NULL by the HAL. Please implement get_vendor_tag_ops in camera_common.h * instead. */ void (*get_metadata_vendor_tag_ops)(const struct camera3_device*, vendor_tag_query_ops_t* ops); /** * dump: * * Print out debugging state for the camera device. This will be called by * the framework when the camera service is asked for a debug dump, which * happens when using the dumpsys tool, or when capturing a bugreport. * * The passed-in file descriptor can be used to write debugging text using * dprintf() or write(). The text should be in ASCII encoding only. * * Performance requirements: * * This must be a non-blocking call. The HAL should return from this call * in 1ms, must return from this call in 10ms. This call must avoid * deadlocks, as it may be called at any point during camera operation. * Any synchronization primitives used (such as mutex locks or semaphores) * should be acquired with a timeout. */ void (*dump)(const struct camera3_device *, int fd); /** * flush: * * Flush all currently in-process captures and all buffers in the pipeline * on the given device. The framework will use this to dump all state as * quickly as possible in order to prepare for a configure_streams() call. * * No buffers are required to be successfully returned, so every buffer * held at the time of flush() (whether successfully filled or not) may be * returned with CAMERA3_BUFFER_STATUS_ERROR. Note the HAL is still allowed * to return valid (CAMERA3_BUFFER_STATUS_OK) buffers during this call, * provided they are successfully filled. * * All requests currently in the HAL are expected to be returned as soon as * possible. Not-in-process requests should return errors immediately. Any * interruptible hardware blocks should be stopped, and any uninterruptible * blocks should be waited on. * * flush() may be called concurrently to process_capture_request(), with the expectation that * process_capture_request will return quickly and the request submitted in that * process_capture_request call is treated like all other in-flight requests. Due to * concurrency issues, it is possible that from the HAL's point of view, a * process_capture_request() call may be started after flush has been invoked but has not * returned yet. If such a call happens before flush() returns, the HAL should treat the new * capture request like other in-flight pending requests (see #4 below). * * More specifically, the HAL must follow below requirements for various cases: * * 1. For captures that are too late for the HAL to cancel/stop, and will be * completed normally by the HAL; i.e. the HAL can send shutter/notify and * process_capture_result and buffers as normal. * * 2. For pending requests that have not done any processing, the HAL must call notify * CAMERA3_MSG_ERROR_REQUEST, and return all the output buffers with * process_capture_result in the error state (CAMERA3_BUFFER_STATUS_ERROR). * The HAL must not place the release fence into an error state, instead, * the release fences must be set to the acquire fences passed by the framework, * or -1 if they have been waited on by the HAL already. This is also the path * to follow for any captures for which the HAL already called notify() with * CAMERA3_MSG_SHUTTER but won't be producing any metadata/valid buffers for. * After CAMERA3_MSG_ERROR_REQUEST, for a given frame, only process_capture_results with * buffers in CAMERA3_BUFFER_STATUS_ERROR are allowed. No further notifys or * process_capture_result with non-null metadata is allowed. * * 3. For partially completed pending requests that will not have all the output * buffers or perhaps missing metadata, the HAL should follow below: * * 3.1. Call notify with CAMERA3_MSG_ERROR_RESULT if some of the expected result * metadata (i.e. one or more partial metadata) won't be available for the capture. * * 3.2. Call notify with CAMERA3_MSG_ERROR_BUFFER for every buffer that won't * be produced for the capture. * * 3.3 Call notify with CAMERA3_MSG_SHUTTER with the capture timestamp before * any buffers/metadata are returned with process_capture_result. * * 3.4 For captures that will produce some results, the HAL must not call * CAMERA3_MSG_ERROR_REQUEST, since that indicates complete failure. * * 3.5. Valid buffers/metadata should be passed to the framework as normal. * * 3.6. Failed buffers should be returned to the framework as described for case 2. * But failed buffers do not have to follow the strict ordering valid buffers do, * and may be out-of-order with respect to valid buffers. For example, if buffers * A, B, C, D, E are sent, D and E are failed, then A, E, B, D, C is an acceptable * return order. * * 3.7. For fully-missing metadata, calling CAMERA3_MSG_ERROR_RESULT is sufficient, no * need to call process_capture_result with NULL metadata or equivalent. * * 4. If a flush() is invoked while a process_capture_request() invocation is active, that * process call should return as soon as possible. In addition, if a process_capture_request() * call is made after flush() has been invoked but before flush() has returned, the * capture request provided by the late process_capture_request call should be treated like * a pending request in case #2 above. * * flush() should only return when there are no more outstanding buffers or * requests left in the HAL. The framework may call configure_streams (as * the HAL state is now quiesced) or may issue new requests. * * Note that it's sufficient to only support fully-succeeded and fully-failed result cases. * However, it is highly desirable to support the partial failure cases as well, as it * could help improve the flush call overall performance. * * Performance requirements: * * The HAL should return from this call in 100ms, and must return from this * call in 1000ms. And this call must not be blocked longer than pipeline * latency (see S7 for definition). * * Version information: * * only available if device version >= CAMERA_DEVICE_API_VERSION_3_1. * * Return values: * * 0: On a successful flush of the camera HAL. * * -EINVAL: If the input is malformed (the device is not valid). * * -ENODEV: If the camera device has encountered a serious error. After this * error is returned, only the close() method can be successfully * called by the framework. */ int (*flush)(const struct camera3_device *); /* reserved for future use */ void *reserved[8]; } camera3_device_ops_t; /********************************************************************** * * Camera device definition * */ typedef struct camera3_device { /** * common.version must equal CAMERA_DEVICE_API_VERSION_3_0 to identify this * device as implementing version 3.0 of the camera device HAL. * * Performance requirements: * * Camera open (common.module->common.methods->open) should return in 200ms, and must return * in 500ms. * Camera close (common.close) should return in 200ms, and must return in 500ms. * */ hw_device_t common; camera3_device_ops_t *ops; void *priv; } camera3_device_t; __END_DECLS #endif /* #ifdef ANDROID_INCLUDE_CAMERA3_H */