I recently got a Tivo Roamio and started copying some recordings onto DVD media. I use kmttg to download and decode the program streams and then author and burn. The resulting DVDs plays correctly in several set top DVD players that I have.
But now I would like to take a step back and edit the mpg file before I author the DVD. I like to use Cuttermaran and/or Mpeg2Schnitt to perform the cuts as I like the editing features that they have. Both these editors require elementary streams as input. This is not a problem as I have several de-muxers that I have used with other video sources and edited, authored and burned with no problems.
But I face a problem with Tivo files. For example.......
Video.mpg is 37 minutes, 720x480, 16x9, 29.97
The mpg file length is 37 minutes long and when I demux it I get:
Video.m2v 34 minutes, 720x480, 16x9, 29.97
Video.ac3 37 minutes, 192kb/s, 48.0kHz
The difference in the video and audio stream times is causing a problem. When I open these streams in Cuttermaran or Mpeg2Schnitt the video and audio start out in sync but gradually goes out of sync as the video is running fast. The audio speed is correct. I tried a number of different demuxers and the result is the same. I tried a number of video tools to try to correct the video stream and always end up with 34 minutes and runs too fast in the editor. Interestingly if I re-mux the steams back together the mpg video file has the video and audio in sync from the begging to the end and runs at the correct speed and 37 minutes in length.
If I re-encode the mpg file this will correct the video duration problem that I am seeing after demuxing but I do not what to do this as the video quality will suffer and it takes a long time to process the file.
Does anyone have an idea what is going on in the mpg file with regard to timing and how I can get the demuxed video at the correct speed?
Thanks.
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