[MPlayer-users] concatenate mpegs

[Ville Saari]

On Thu, Mar 04, 2004 at 11:41:23AM +0100, Michel Bardiaux wrote:

> Concatenation will only work *well* under 2 conditions:
...
> (2) The timestamps form a coherent sequence.

Many (or most) DVD:s don't fullfill that condition. To my experience
only a small minority has a contiguous time code throughout the whole
movie.

Ripping Star Trek VI was a real pain because of this. The DVD had
burned-in subtitles for Klingon language phrases placed on the
bottom black bar. I didn't want to retain the black bars, so I
recreated the subtitles as an mpsub file and wanted to render
them on the picture while transcoding.

The problem was that mplayer needs a time code to synchronize the
subtitles with. The mpeg2-stream on DVD was apparently concatenated
from several dozens of small clips that each had their own time code.
So the time code was reset to zero every few minutes.

I tried to solve the problem by first encoding to a fifo with a lossless
codec and then ancoding this fifo to the final mpeg4 avi adding the
subtitles in the process. However I couldn't get this to work and I
had no disk space for actully storing the losslessly compressed temporary
file so I had to first encode it into an mpeg4 with absurdly high
quality settings and then re-encode this to the final file with
subtitles.

-- 
 Ville