Android Camera2 Api - OnImageAvailable Is Not Invoked After Session.capture

I am trying to use camera api2 to capture images. The code worked fine on MOTO g4, but when I test the code on NEXUS 6, the onImageAvailable is not invoked after session.capture, a

Solution 1:

It'd be helpful if you included full logcat output from the failing device, but I suspect the problem is this:

ImageReader reader = ImageReader.newInstance(width, height, ImageFormat.JPEG, 1);

You're creating a local ImageReader object, and not saving it for further use. You do get a Surface from it, but a Surface is much like a weak pointer; it will not keep the ImageReader from getting GC'd if nothing references it (see the note in the developer references)

So I suspect if you just create a class member mReader variable, and store reader in that, everything will work OK.

It may be working on the Moto phone due to differences in the GC algorithm; the runtime just hadn't gotten around to clearing out the reader object quite yet, so it has time to invoke the callback.

Solution 2:

Override onConfigureFailed() like this:

   @Override
   public void onConfigureFailed(CameraCaptureSession session) {
       ImageReader mReader = ImageReader.newInstance(640, 480, ImageFormat.JPEG, 1);
       takePicture() // function to get image
       createCameraPreview(); // function to set camera Preview on screen
   }

Call createCameraPreview function to restart the camera, otherwise, it will stay stuck. You can change the ImageReader with new values

ImageReader mReader = ImageReader.newInstance(640, 480, ImageFormat.JPEG, 1);

And call the takePicture() function again so that user don't have to click again to capture image.