Android org.webrtc.VideoRenderer.I420Frame arrays to PreviewCallback.onPreviewFrame byte[]

Question

I keep hoping some code will appear on the internet, but getting nowhere ;)

WebRTC incoming I420Frame object seems to have 3 arrays of yuvPlanes

A typical An

Answer 1

OK, here you go:

// Copy the bytes out of |src| and into |dst|, ignoring and overwriting
// positon & limit in both buffers.
//** copied from org/webrtc/VideoRenderer.java **//
private static void copyPlane(ByteBuffer src, ByteBuffer dst) {
  src.position(0).limit(src.capacity());
  dst.put(src);
  dst.position(0).limit(dst.capacity());
}

public static android.graphics.YuvImage ConvertTo(org.webrtc.VideoRenderer.I420Frame src, int imageFormat) {
    switch (imageFormat) {
    default:
        return null;

    case android.graphics.ImageFormat.YV12: {
        byte[] bytes = new byte[src.yuvStrides[0]*src.height +
                            src.yuvStrides[1]*src.height/2 + 
                            src.yuvStrides[2]*src.height/2];
        ByteBuffer tmp = ByteBuffer.wrap(bytes, 0, src.yuvStrides[0]*src.height);
        copyPlane(src.yuvPlanes[0], tmp);
        tmp = ByteBuffer.wrap(bytes, src.yuvStrides[0]*src.height, src.yuvStrides[2]*src.height/2);
        copyPlane(src.yuvPlanes[2], tmp);
        tmp = ByteBuffer.wrap(bytes, src.yuvStrides[0]*src.height+src.yuvStrides[2]*src.height/2, src.yuvStrides[1]*src.height/2);
        copyPlane(src.yuvPlanes[1], tmp);
        int[] strides = src.yuvStrides.clone();
        return new YuvImage(bytes, imageFormat, src.width, src.height, strides);
    }

    case android.graphics.ImageFormat.NV21: {
        if (src.yuvStrides[0] != src.width)
            return convertLineByLine(src);
        if (src.yuvStrides[1] != src.width/2)
            return convertLineByLine(src);
        if (src.yuvStrides[2] != src.width/2)
            return convertLineByLine(src);

        byte[] bytes = new byte[src.yuvStrides[0]*src.height +
                            src.yuvStrides[1]*src.height/2 + 
                            src.yuvStrides[2]*src.height/2];
        ByteBuffer tmp = ByteBuffer.wrap(bytes, 0, src.width*src.height);
        copyPlane(src.yuvPlanes[0], tmp);

        byte[] tmparray = new byte[src.width/2*src.height/2];
        tmp = ByteBuffer.wrap(tmparray, 0, src.width/2*src.height/2);

        copyPlane(src.yuvPlanes[2], tmp);
        for (int row=0; row

This converts I420Frame to Android YuvImage of android.graphics.ImageFormat.NV21, which you can compressToJpeg(). ImageFormat.YV12 support seems to be limited in SDK. Note that the Y and V must be shuffled.

Most error checking is skipped for brevity.