I've been struggling with encoding videos using FFMPEG and x264. The output stutters when played back in Quicktime, while in VLC it shows a lot of compression artifacts at the same places Quicktime stutters. So it seems like Quicktime is stuttering because it's trying to suppress the corruption/artifacts.
The videos have a lot of random motion in them, including frames where 75% of the pixels will change at a random interval (the video is software generated so it's truly pseudo-random). The compression seems to be choking in these places where it's likely detecting a "scene cut" incorrectly. It also seems to choke at regular intervals where I guess it's doing a keyframe.
I've based my encoding preset off of the x264-hq preset that comes with FFMPEG. I've tried turning off scene cut detection, and playing with the keyint/g and keyint_min options. Setting g to 1 makes it work, but blows out the filesize. I've tried the lossless presets, but they won't playback at all in Quicktime. Oddly, I haven't had any problems when working with a lower-resolution test video (1440x810).
Here's the preset I have right now, which works, but yields a file that's approximately 60% larger than the (non-working) hq preset yields. Is there any way to improve upon this? The filesize doesn't matter much, I just want something that will playback anywhere and be very high quality.
coder=1 flags=+loop cmp=+chroma partitions=+parti8x8+parti4x4+partp8x8+partp4x4+partb8x8 me_method=umh subq=8 me_range=16 g=1 keyint_min=1 sc_threshold=0 i_qfactor=0.71 b_strategy=1crf=20 qcomp=0.6 qmin=20 qmax=51 qdiff=4 bf=16 refs=4 trellis=1 flags2=+dct8x8+wpred+bpyramid+mixed_refs wpredp=2
Here's the command:
ffmpeg \ -r 60 -i "frame-%06d.tiff" \ -vcodec libx264 -vpre my_preset \ -threads 0 \ -r 60 -an -f out.mp4
