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So I'm getting Image objects from Android's Camera2 API, then I convert them to OpenCV Mat objects via their byte buffers. The YUV_420_888 format is what I set as the output of the camera as recommended by the docs, but when I try converting the Mat from YUV to RGB, all it shows is green.

Following the answers from this thread, this is how I convert the Mat:

Image image = reader.acquireLatestImage();

ByteBuffer buffer = image.getPlanes()[0].getBuffer();
byte[] bytes = new byte[buffer.remaining()];
buffer.get(bytes);

Mat mat = new Mat(image.getHeight()+image.getHeight()/2, image.getWidth(), CvType.CV_8UC1);
mat.put(0, 0, bytes);
Mat rgb = new Mat(image.getHeight(), image.getWidth(), CvType.CV_8UC4);
Imgproc.cvtColor(mat, rgb, Imgproc.COLOR_YUV420sp2BGR, 4);

After these lines, all I did next was use imwrite to write the mats to disk. For reference, here's some sample images resulting from the writes:

YUV - http://i.imgur.com/qm765AZ.jpg (straight from the Camera2 API, no processing yet)

RGB - http://i.imgur.com/FzLx2Cc.jpg (the exact same image, but converted from YUV to RGB)

Any insights as to why the RGB image looks the way it does? Thank you in advance!

So I'm getting Image objects from Android's Camera2 API, then I convert them to OpenCV Mat objects via their byte buffers. The YUV_420_888 format is what I set as the output of the camera as recommended by the docs, but when I try converting the Mat from YUV to RGB, all it shows is green.

Following the answers from this thread, this is how I convert the Mat:

Image image = reader.acquireLatestImage();

ByteBuffer buffer = image.getPlanes()[0].getBuffer();
byte[] bytes = new byte[buffer.remaining()];
buffer.get(bytes);

Mat mat = new Mat(image.getHeight()+image.getHeight()/2, image.getWidth(), CvType.CV_8UC1);
mat.put(0, 0, bytes);
Mat rgb = new Mat(image.getHeight(), image.getWidth(), CvType.CV_8UC4);
Imgproc.cvtColor(mat, rgb, Imgproc.COLOR_YUV420sp2BGR, 4);

After these lines, all I did next was use imwrite to write the mats to disk. For reference, here's some sample images resulting from the writes:

YUV - http://i.imgur.com/qm765AZ.jpg (straight from the Camera2 API, no processing yet)

RGB - http://i.imgur.com/FzLx2Cc.jpg (the exact same image, but converted from YUV to RGB)

Any insights as to why the RGB image looks the way it does? I've also tried a whole lot of other conversion options besides COLOR_YUV420sp2BGR, but they all seem to have the same effect, which is a green image. Thank you in advance!

So I'm getting Image objects from Android's Camera2 API, then I convert them to OpenCV Mat objects via their byte buffers. The YUV_420_888 format is what I set as the output of the camera as recommended by the docs, but when I try converting the Mat from YUV to RGB, all it shows is green.

Following the answers from this thread, this is how I convert the Mat:

Image image = reader.acquireLatestImage();

ByteBuffer buffer = image.getPlanes()[0].getBuffer();
byte[] bytes = new byte[buffer.remaining()];
buffer.get(bytes);

Mat mat = new Mat(image.getHeight()+image.getHeight()/2, image.getWidth(), CvType.CV_8UC1);
mat.put(0, 0, bytes);
Mat rgb = new Mat(image.getHeight(), image.getWidth(), CvType.CV_8UC4);
Imgproc.cvtColor(mat, rgb, Imgproc.COLOR_YUV420sp2BGR, 4);

After these lines, all I did next was use imwrite to write the mats to disk. For reference, here's some sample images resulting from the writes:

YUV - http://i.imgur.com/qm765AZ.jpg (straight from the Camera2 API, no processing yet)

RGB - http://i.imgur.com/FzLx2Cc.jpg (the exact same image, but converted from YUV to RGB)

Any insights as to why the RGB image looks the way it does? I've also tried a whole lot of other conversion options besides COLOR_YUV420sp2BGR, but they all seem to have the same effect, which is a green image. Thank you in advance!