Bitmap to Mat gives wrong colors back

Question

So I make a bitmap from a blob with the next code:

byte[] blob = contact.getMP();
ByteArrayInputStream inputStream = new ByteArrayInputStream(blob);
Bitmap b         


        

Answer 1

The format of color channels in Android Bitmap are RGB But in opencv Mat, the channels are BGR by default.

So when you do Utils.bitmapToMat(), [B,G,R] values are stored in [R,G,B] channels. The red and blue channels are interchanged.

One possible solution is to apply cvtcolor on the opencv Mat you got as below: Imgproc.cvtColor(ImageMat, ImageMat, Imgproc.COLOR_BGR2RGB);

It worked for me.