Android text recognition - Throttling the text recognizer

Question

I'm testing the android vision text recognizer, and in real-time use, the docs suggest I "Throttle calls to the text recognizer. If a new video frame becomes available while the text recognizer is running, drop the frame."

In the sample ocr-reader app, which shares the CameraSource and OcrDetectorProcessor with the ML Kit sample app, I'm trying to figure out precisely how this is accomplished. Can someone point me in the right direction? I'm lookng at the CameraPreviewCallback and FrameProcessingRunnable classes, but no progress yet. Thanks!

Answer 1

I had the exact same question, but I managed to do it like this: it is quite "manual", the idea is to have a flag before passing the processImage to your detector.

private var isProcessing = AtomicBoolean(false)

private fun process(image: FirebaseVisionImage) {
        isProcessing.set(true)
        detector.processImage(image)
            .addOnSuccessListener { texts ->
                processTextRecognitionResult(texts)
                isProcessing.set(false)
            }

            .addOnFailureListener {
                println("Detection failed with $it")
            }
    }

So basically

override fun analyze(imageProxy: ImageProxy?, degrees: Int) {
        imageProxy?.image?.let { image ->
            if(!isProcessing.get()) {
               process(image)
            }
        }
    }