Merge "Camera: Improve logical camera RAW capture docs" into sc-dev am: 597454da

     * camera's crop region is set to maximum size, the FOV of the physical streams for the

     * ultrawide lens will be the same as the logical stream, by making the crop region

     * smaller than its active array size to compensate for the smaller focal length.</p>

     * <p>Even if the underlying physical cameras have different RAW characteristics (such as

     * size or CFA pattern), a logical camera can still advertise RAW capability. In this

     * case, when the application configures a RAW stream, the camera device will make sure

     * the active physical camera will remain active to ensure consistent RAW output

     * behavior, and not switch to other physical cameras.</p>

     * <p>There are two ways for the application to capture RAW images from a logical camera

     * with RAW capability:</p>

     * <ul>

     * <li>Because the underlying physical cameras may have different RAW capabilities (such

     * as resolution or CFA pattern), to maintain backward compatibility, when a RAW stream

     * is configured, the camera device makes sure the default active physical camera remains

     * active and does not switch to other physical cameras. (One exception is that, if the

     * logical camera consists of identical image sensors and advertises multiple focalLength

     * due to different lenses, the camera device may generate RAW images from different

     * physical cameras based on the focalLength being set by the application.) This

     * backward-compatible approach usually results in loss of optical zoom, to telephoto

     * lens or to ultrawide lens.</li>

     * <li>Alternatively, to take advantage of the full zoomRatio range of the logical camera,

     * the application should use <a href="https://developer.android.com/reference/android/hardware/camera2/MultiResolutionImageReader.html">MultiResolutionImageReader</a>

     * to capture RAW images from the currently active physical camera. Because different

     * physical camera may have different RAW characteristics, the application needs to use

     * the characteristics and result metadata of the active physical camera for the

     * relevant RAW metadata.</li>

     * </ul>

     * <p>The capture request and result metadata tags required for backward compatible camera

     * functionalities will be solely based on the logical camera capabiltity. On the other

     * functionalities will be solely based on the logical camera capability. On the other

     * hand, the use of manual capture controls (sensor or post-processing) with a

     * logical camera may result in unexpected behavior when the HAL decides to switch

     * between physical cameras with different characteristics under the hood. For example,