Notes
How to convert a YUV (NV12) raw image
ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt nv12 -s {WIDTH}x{HEIGHT} -i input.yuv output.png
ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt nv12 -s {WIDTH}x{HEIGHT} -i input.yuv output.png