How to convert byte array to Mat object in Java

Question

I want to convert byte array to Mat object, but it throws

java.lang.UnsupportedOperationException: Provided data element number (60181) should be multiple of the Mat channels count (3)
    at org.opencv.core.Mat.put(Mat.java:992)

It is my code:

byte[] bytes = FileUtils.readFileToByteArray(new File("aaa.jpg"));

Mat mat = new Mat(576, 720, CvType.CV_8UC3);
//Imgcodecs.imencode(".jpg", mat, new MatOfByte(bytes));
mat.put(0, 0, bytes);

I tried many ways and also googled a lot, but did not find any solution.

Note: I know Imgcodecs.imread("aaa.jpg"); and

BufferedImage img = ImageIO.read(new ByteArrayInputStream(byteArray));
Mat mat = new Mat(img.getHeight(), img.getWidth(), CvType.CV_8UC3);
mat.put(0, 0, ((DataBufferByte) img.getRaster().getDataBuffer()).getData());

But I want to directly convert byte array to Mat without any extra process to speed up the process time.

Thanks in advance!

Answer 1

I solved the problem like this:

byte[] bytes = FileUtils.readFileToByteArray(new File("aaa.jpg"));
Mat mat = Imgcodecs.imdecode(new MatOfByte(bytes), Imgcodecs.CV_LOAD_IMAGE_UNCHANGED);

Now it works well and much faster than *bytes->BufferedImage->Mat*