I have a quick time video file, video stream is in motion jpeg format, I extract every frame in the file with
ffmpeg -i a.mov -vcodec copy -f image2 %d.jpg
I found that in every jpeg file, there are actually two
FFD8 marker, which means there are actually two images in one single jpeg file.
Is this correct? Is the file interlaced? Anything special need to pass to codec?