I am using camera2 API to capture images with manual exposure and ISO. But sometimes the image captured has different values for ISO and exposure then the one I have specified.
Is there any way I could pass the information of the values that I set in the capture request to the image reader listener where callback comes when image is captured to see if the image is actually having the values that I specified.
I am capturing a lot of images(say a loop) with different values of ISO and exposure for every image.
This is my code to capture images:
imageReader = ImageReader.newInstance(imageWidth, imageHeight, ImageFormat.JPEG, 1);
imageReader.setOnImageAvailableListener(new ImageReader.OnImageAvailableListener() {
@Override
public void onImageAvailable(ImageReader imageReader) {
/// How to check the image is taken with correct values
}
}, backgroundHandler);
captureRequest = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureRequest.addTarget(preview);
captureRequest.addTarget(imageReader.getSurface());
captureRequest.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_OFF);
captureRequest.set(CaptureRequest.CONTROL_MODE, CaptureRequest.CONTROL_MODE_OFF);
captureRequest.set(CaptureRequest.SENSOR_SENSITIVITY, <MANUAL_ISO>);
captureRequest.set(CaptureRequest.SENSOR_EXPOSURE_TIME, <MANUAL_EXPOSURE>);
mSession.capture(captureRequest.build(), null, backgroundHandler);
This works most of the times, like if I am taking 100 photos then around 70 are taken with the values I specify and rest 30 will have different values.
What I tried:
I have tried below approach where, when I capture image, I check the values in onCaptureCompleted and create a queue indicating whether the image is taken with correct values or not. But when I get image in imageReader, I have no idea if the value in queue is for current image or some other image. This happens because I don't know when will imageReader listener be invoked for a image: It can be invoked just after onCaptureCompleted finishes or before it, or in worst case after onCaptureCompleted is invoked 2-3 times for 2-3 images as I am capturing images in loop.
Basically I need a tag to identify images in this approach but I don't know how to do that.
Here is the code for the same:
class CapturedPicture {
static Queue<Boolean> iso = new LinkedList<>();
}
mSession.capture(captureRequest.build(), new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) {
super.onCaptureCompleted(session, request, result);
int capturedISO = result.get(CaptureResult.SENSOR_SENSITIVITY);
CapturedPicture.iso.add(<MANUAL_ISO> == capturedISO);
}
}, backgroundHandler);
So I need a way to pass information to imageReader listener to indicate if the current image conforms to the settings I specified. Any help is appreciated.
PS: I also tried saving TotalCaptureResult's SENSOR_TIMESTAMP and image.getTimestamp and comparing them but I can confirm sometimes the image with some timestamp doesn't have same parameters as captured from totalCaptureResult.
