I have been tinkering around with some flv files that I downloaded from CBS.com. I am trying to remux them into mp4 containers so that I can push them up to my Tivo to watch them. I am having no luck. I tried flvextract to extract the elementary streams. That seems to work fine. Then I try to remux them with either mp4box or mp4creator and I end up with a mp4 file that is roughly half the total size as the flv. It doesn't play back in MPCHC (blank screen and timeline doesn't progress).

I found a thread on this where someone uses ffmpeg to copy both streams into a mp4, and then extracts the elementary streams with mp4box and then remuxes them again with mp4box. That doesn't work either.

I then tried encoding the file with avisynth (ffmpegsource2+assumefps(24)) and x264 (r1745). That also doesn't play in MPCHC.

This is on a new laptop, so it is possible that I don't have something set up correctly. Don't know.

What am I doing wrong? Also, flvextract will output a timecode file when I demux a flv. What is that used for?

MediaInfo on flv: