Add new raw image sensor HAL pixel format.

This format is exposed outside of the HAL to applications.

RAW_SENSOR is a single-channel 16-bit format, typically representing raw
Bayer-pattern images from an image sensor, with minimal processing.

The exact pixel layout of the data in the buffer is sensor-dependent, and
needs to be queried from the camera device.

Generally, not all 16 bits are used; more common values are 10 or 12
bits. All parameters to interpret the raw data (black and white points,
color space, etc) must be queried from the camera device.

This format assumes
- an even width
- an even height
- a horizontal stride multiple of 16 pixels (32 bytes).

Change-Id: I67fc72d1c2c899e258fcd53b3ab91b459e9210f0

include/system/graphics.h

@@ -86,7 +86,27 @@ enum {
      */
     HAL_PIXEL_FORMAT_YV12   = 0x32315659, // YCrCb 4:2:0 Planar
 
-
+    /*
+     * Android RAW sensor format:
+     *
+     * This format is exposed outside of the HAL to applications.
+     *
+     * RAW_SENSOR is a single-channel 16-bit format, typically representing raw
+     * Bayer-pattern images from an image sensor, with minimal processing.
+     *
+     * The exact pixel layout of the data in the buffer is sensor-dependent, and
+     * needs to be queried from the camera device.
+     *
+     * Generally, not all 16 bits are used; more common values are 10 or 12
+     * bits. All parameters to interpret the raw data (black and white points,
+     * color space, etc) must be queried from the camera device.
+     *
+     * This format assumes
+     * - an even width
+     * - an even height
+     * - a horizontal stride multiple of 16 pixels (32 bytes).
+     */
+    HAL_PIXEL_FORMAT_RAW_SENSOR = 0x20,
 
     /* Legacy formats (deprecated), used by ImageFormat.java */
     HAL_PIXEL_FORMAT_YCbCr_422_SP       = 0x10, // NV16