As you know, the AIMAGE_FORMAT_YUV_420_888 format can be planar (YV12) or semi-planar (NV21):

This format is a generic YCbCr format, capable of describing any 4:2:0 chroma-subsampled planar or semiplanar buffer (but not fully interleaved), with 8 bits per color sample.

For example, on my phone I'm pretty sure the image is planar at <=720p and semi-planar at 1080p.

This logic in cap_android_camera.cpp fails to detect the format at 1080p:

    if ( (uvPixelStride == 2) && (uPixel == vPixel + 1) && (yLen == frameWidth * frameHeight) && (uLen == ((yLen / 2) - 1)) && (vLen == uLen) ) {
        colorFormat = COLOR_FormatYUV420SemiPlanar;
        if (fourCC == FOURCC_UNKNOWN) {
            fourCC = FOURCC_NV21;
        }
    } else if ( (uvPixelStride == 1) && (uPixel == vPixel + vLen) && (yLen == frameWidth * frameHeight) && (uLen == yLen / 4) && (vLen == uLen) ) {
        colorFormat = COLOR_FormatYUV420Planar;
        if (fourCC == FOURCC_UNKNOWN) {
            fourCC = FOURCC_YV12;
        }
    } else {
        colorFormat = COLOR_FormatUnknown;
        fourCC = FOURCC_UNKNOWN;
        LOGE("Unsupported format");
        return false;
    }

Here are values for these AImage variables for different resolutions:

So at least one condition (yLen == frameWidth * frameHeight) is not always correct.

I came across this bug because setting CAP_PROP_FOURCC to NV21 or YV12 always fails, only RGB is successful; and read() always fails for 1080p no matter the format.

System information (version)

• OpenCV => ❔
• Operating System / Platform => ❔
• Compiler => ❔

Detailed description

Steps to reproduce

Issue submission checklist

• I report the issue, it's not a question
• I checked the problem with documentation, FAQ, open issues,
  forum.opencv.org, Stack Overflow, etc and have not found any solution
• I updated to the latest OpenCV version and the issue is still there
• There is reproducer code and related data files: videos, images, onnx, etc