/** Writes Image data into a {@code ByteBuffer}. */
  private void convertBitmapToByteBuffer(Bitmap bitmap) {
    if (imgData == null) {
      return;
    }
    imgData.rewind();
    bitmap.getPixels(intValues, 0, bitmap.getWidth(), 0, 0, bitmap.getWidth(), bitmap.getHeight());
    // Convert the image to floating point.
    int pixel = 0;
    long startTime = SystemClock.uptimeMillis();
    for (int i = 0; i < getImageSizeX(); ++i) {
      for (int j = 0; j < getImageSizeY(); ++j) {
        final int val = intValues[pixel++];
        addPixelValue(val);
      }
    }
    long endTime = SystemClock.uptimeMillis();
    Log.d(TAG, "Timecost to put values into ByteBuffer: " + Long.toString(endTime - startTime));
  }
 
 
 
 void classifyFrame(Bitmap bitmap, SpannableStringBuilder builder) {
    if (tflite == null) {
      Log.e(TAG, "Image classifier has not been initialized; Skipped.");
      builder.append(new SpannableString("Uninitialized Classifier."));
    }
    convertBitmapToByteBuffer(bitmap);
    // Here's where the magic happens!!!
    long startTime = SystemClock.uptimeMillis();
    runInference();
    long endTime = SystemClock.uptimeMillis();
    Log.d(TAG, "Timecost to run model inference: " + Long.toString(endTime - startTime));

    // Smooth the results across frames.
    applyFilter();

    // Print the results.
    printTopKLabels(builder);
    long duration = endTime - startTime;
    SpannableString span = new SpannableString(duration + " ms");
    span.setSpan(new ForegroundColorSpan(android.graphics.Color.LTGRAY), 0, span.length(), 0);
    builder.append(span);
  }