Camera3: SHUTTER event for reprocessing
Clarify that the SHUTTER event should be sent when HAL
start processing a reprocess request but the timestamp
should be the input image's start of exposure.
Bug: 21112186
Change-Id: I5bd32b749adc5e82e9a311ec4b123fd807a30d36
diff --git a/include/hardware/camera3.h b/include/hardware/camera3.h
index fd3a45d..73726cf 100644
--- a/include/hardware/camera3.h
+++ b/include/hardware/camera3.h
@@ -194,8 +194,13 @@
* not-yet-registered streams.
*
* 9. When the capture of a request begins (sensor starts exposing for the
- * capture), the HAL calls camera3_callback_ops_t->notify() with the SHUTTER
- * event, including the frame number and the timestamp for start of exposure.
+ * 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:
*
@@ -207,7 +212,8 @@
* 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.
+ * 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.
@@ -1787,7 +1793,7 @@
CAMERA3_MSG_ERROR = 1,
/**
- * The exposure of a given request has
+ * The exposure of a given request or processing a reprocess request has
* begun. camera3_notify_msg.message.shutter contains the information
* the capture.
*/
@@ -1878,12 +1884,13 @@
*/
typedef struct camera3_shutter_msg {
/**
- * Frame number of the request that has begun exposure
+ * Frame number of the request that has begun exposure or reprocessing.
*/
uint32_t frame_number;
/**
- * Timestamp for the start of capture. This must match the capture result
+ * 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;
@@ -2357,9 +2364,10 @@
* >= 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 has been received
- * via a SHUTTER notify() call. It is highly recommended to
- * dispatch this call as early as possible.
+ * 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: