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Setting VideoCapture to certain square resolutions results in garbled output #99

@dev-sda1

Description

@dev-sda1

I'm currently using OpenCV on a Pi 4 with the ArmV7L native library loaded. When I try to capture an image through the Pi Camera with square resolutions from 700x700 to 790x790 in increments of 10, the image is completely garbled. Setting the capture to a non-square resolution like 700x730 results in a clear image.

Square resolutions tried that result in a garbled image:

  • 700x700
  • 710x710
  • 720x720
  • 730x730
  • 740x740
  • 750x750
  • 760x760
  • 770x770
  • 780x780
  • 790x790

Expected result: The image shouldn't be garbled, with whatever's in shot clearly visible.
colour
grey

What actually happens: The image is a garbled mess, nothing is visible.
colour
grey

Reproduction Code:

try {
        VideoCapture camera = new VideoCapture(0);
        camera.set(Videoio.CAP_PROP_FRAME_WIDTH, 700);
        camera.set(Videoio.CAP_PROP_FRAME_HEIGHT, 700);
        if (camera.isOpened()) {
          Mat image = new Mat();
          MatOfByte buffer = new MatOfByte();
          if(colour) {
            camera.read(image);
            Imgcodecs.imencode(".jpg", image, buffer);
          }else{
            camera.read(image);
            Imgproc.cvtColor(image, image, Imgproc.COLOR_BGR2GRAY);
            Imgcodecs.imencode(".jpg", image, buffer);
          }

          // Converting the mat into a BufferedImage
          this.image = ImageIO.read(new ByteArrayInputStream(buffer.toArray()));
        }

        camera.release();
    }catch(Exception e){
        e.printStackTrace();
    }

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