Android CameraX how to rotate output video

Question

I use the following versions of CameraX dependencies:

implementation "androidx.camera:camera-camera2:1.0.0-beta04"
implementation "androidx.camera:camera-view:1.0.0-alpha11"
implementation "androidx.camera:camera-extensions:1.0.0-alpha11"
implementation "androidx.camera:camera-lifecycle:1.0.0-beta04"

And try to encode output video from the camera into H264 using android MediaCodec and decode it back and show the result video on a SurfaceView, everything works fine except that the video on a SurfaceView is conterclockwise rotated by 90 degrees in portrait mode and has no rotation in landscape mode.

My code of capturing video from the camera looks like this:

private lateinit var yData: ByteArray  //
private lateinit var uData: ByteArray  // store YUV data from camera
private lateinit var vData: ByteArray  //

imageAnalysis = ImageAnalysis.Builder().setBackpressureStrategy ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST).build()
imageAnalysis.setAnalyzer(executor, ImageAnalysis.Analyzer { imageProxy ->
    if (imageProxy.image == null || imageProxy.planes.size < 3) return@Analyzer

    for (i in 0 until 3) {
        val plane = imageProxy.image!!.planes[i]
        val bytes = ByteArray(plane.buffer.remaining())
        plane.buffer.get(bytes)
        when(i) {
            0 -> yData = bytes
            1 -> uData = bytes
            2 -> vData = bytes
        }
    }
    imageProxy.close()

    // send yData, uData, vData to encoder ...
})

To solve the problem I tried to use: imageAnalysis.targetRotation = Surface.ROTATION_0 and other values but it doesn't work at all - the decoded video still rotated.

Also I tried to rotate YUV data that I get from the camera using this answer and this time I succeeded in rotating my video, BUT the colors of the video suddenly gets dark and I have no idea why.. but if I don't rotate my video the colors are perfect.

So my question is: how can I correctly rotate my video without colors distortion? The way when I need to rotate my SurfaceView isn't fit for me. And I repeat - the problem exactly with decoded video that I first get from camera and encode to H264 and not with preview from camera, the preview from camera works fine.

Here my source video without use of any ways that I mentioned above.

And here my video when I use rotation of it's YUV data.

Answer 1

Finally I found a solution - I made an android library, based on Google's libyuv library for easy and fast scaling, rotating and mirroring frames from android Camera2 or CameraX api.