| ## Camera Device HAL ## |
| --- |
| |
| ## Overview: ## |
| |
| The camera.device HAL interface is used by the Android camera service to operate |
| individual camera devices. Instances of camera.device HAL interface can be obtained |
| via one of the ICameraProvider::getCameraDeviceInterface_V<N>_x() methods, where N |
| is the major version of the camera device interface. |
| |
| Obtaining the device interface does not turn on the respective camera device; |
| each camera device interface has an actual open() method to begin an active |
| camera session. Without invoking open(), the interface can be used for querying |
| camera static information. |
| |
| More complete information about the Android camera HAL and subsystem can be found at |
| [source.android.com](http://source.android.com/devices/camera/index.html). |
| |
| ## Version history: ## |
| |
| ### [email protected]: |
| |
| HIDL version of the legacy camera device HAL. Intended as a shim for devices |
| needing to use the deprecated pre-HIDL camera device HAL v1.0. |
| |
| May be used in HIDL passthrough mode for devices upgrading to the Android O |
| release; must be used in binderized mode for devices launching in the O release. |
| |
| It is strongly recommended to not use this interface for new devices, as new |
| devices may not use this interface starting with the Android P release, and all |
| support for ICameraDevice@1.0 will be removed with the Android R release. |
| |
| This HAL interface version only allows support at the LEGACY level for the |
| android.hardware.camera2 API. |
| |
| Added in Android 8.0. |
| |
| Subsidiary HALs: |
| |
| #### [email protected]: |
| |
| Callback interface for obtaining, filling, and returning graphics buffers for |
| preview operation with the ICameraDevice@1.0 inteface. |
| |
| #### [email protected]: |
| |
| Callback interface for sending events and data buffers from the HAL to the |
| camera service. |
| |
| ### [email protected]: |
| |
| HIDL version of the baseline camera device HAL, required for LIMITED or FULL |
| operation through the android.hardware.camera2 API. |
| |
| The main HAL contains methods for static queries about the device, similar to |
| the HALv3-specific sections of the legacy camera module HAL. Simply obtaining an |
| instance of the camera device interface does not turn on the camera device. |
| |
| May be used in passthrough mode for devices upgrading to the Android O release; |
| must be used in binderized mode for all new devices launching with Android O or |
| later. |
| |
| The open() method actually opens the camera device for use, returning a Session |
| interface for operating the active camera. It takes a Callback interface as an |
| argument. |
| |
| Added in Android 8.0. |
| |
| Subsidiary HALs: |
| |
| #### [email protected]: |
| |
| Closely matches the features and operation of the pre-HIDL camera device HAL |
| v3.2, containing methods for configuring an active camera device and submitting |
| capture requests to it. |
| |
| #### [email protected]: |
| |
| Callback interface for sending completed captures and other asynchronous events |
| from tehe HAL to the client. |
| |
| ### [email protected]: |
| |
| A minor revision to the ICameraDevice.hal@3.2. |
| |
| - Adds support for overriding the output dataspace of a stream, which was |
| supported in the legacy camera HAL. |
| |
| Added in Android 8.1. |
| |
| ### [email protected]: |
| |
| A minor revision to the ICameraDevice.hal@3.3. |
| |
| - Adds support for session parameters during stream configuration. |
| |
| Added in Android 9 |
