MultiResolutionImageReader.OnActiveOutputSurfacesListener

onActiveOutputSurfaces

public abstract void onActiveOutputSurfaces (List<Surface> activeOutputSurfaces, 
                long timestamp, 
                long frameNumber)

Callback that is called to notify the active surfaces that the application should expect to receive images from.

If the MultiResolutionImageReader is created with enableConcurrency set to true, multiple underlying readers may produce images for a single capture request. The application can listen to this callback to know which readers to expect an output image from.

If the MultiResolutionImageReader is created without enableConcurrency set to true, this callback will not the triggered.

For each of the activeOutputSurfaces, a ERROR(/ImageReader.onImageAvailableListener.onImageAvailable) will be called. Or in rare cases, ERROR(CameraCaptureSession.onCaptureBufferLost/android.hardware.camera2.CameraCaptureSession#onCaptureBufferLost CameraCaptureSession.onCaptureBufferLost) is called if the buffer is dropped.

The timestamp can be used to correlate between the activeOutputSurfaces and the images being output from those surfaces. The timestamp can be start of exposure or start of readout depending on whether OutputConfiguration.setReadoutTimestampEnabled(boolean) was called on the outputs. Similarly, the timestamp can be either in the same time base as in SystemClock.uptimeMillis() or SystemClock.elapsedRealtime() depending on the timestamp base of the outputs. See ERROR(/OutputConfiguration#setTimestampBase) for details.