convertYUV420ToImage function

Image convertYUV420ToImage(CameraImage cameraImage)

Implementation

image_lib.Image convertYUV420ToImage(CameraImage cameraImage) {
  final width = cameraImage.width;
  final height = cameraImage.height;

  final uvRowStride = cameraImage.planes[1].bytesPerRow;
  final uvPixelStride = cameraImage.planes[1].bytesPerPixel!;

  final yPlane = cameraImage.planes[0].bytes;
  final uPlane = cameraImage.planes[1].bytes;
  final vPlane = cameraImage.planes[2].bytes;

  final image = image_lib.Image(width: width, height: height);

  var uvIndex = 0;

  for (var y = 0; y < height; y++) {
    var pY = y * width;
    var pUV = uvIndex;

    for (var x = 0; x < width; x++) {
      final yValue = yPlane[pY];
      final uValue = uPlane[pUV];
      final vValue = vPlane[pUV];

      final r = yValue + 1.402 * (vValue - 128);
      final g = yValue - 0.344136 * (uValue - 128) - 0.714136 * (vValue - 128);
      final b = yValue + 1.772 * (uValue - 128);

      image.setPixelRgba(x, y, r.toInt(), g.toInt(), b.toInt(), 255);

      pY++;
      if (x % 2 == 1 && uvPixelStride == 2) {
        pUV += uvPixelStride;
      } else if (x % 2 == 1 && uvPixelStride == 1) {
        pUV++;
      }
    }

    if (y % 2 == 1) {
      uvIndex += uvRowStride;
    }
  }
  return image;
}