Cinelerra, high def MPEG from TiVo, slicing out a clip, creating DVD and portable versions

[Jarod Wilson]

On Friday 27 March 2009 08:36:12 Ben Scott wrote:
> SCENARIO
> 
>   I have a one hour, high-definition news program, recorded on my TiVo
> Series 3.  It is roughly 8 GB in size.  I want to extract a short
> segment from that file -- maybe 5 minutes.  Ideally, I'd do this part
> with no loss of quality from re-encoding the compressed stream, but
> I'm willing to take a hit if I have to.  I then want to do two things
> with the clip: (1) Produce a DVD-Video disc which will play in most
> typical DVD players.  (2) Produce a "portable version" which is of
> more suitable file size, and which will play "out of the box" on most
> MS Windows systems (and ideally other systems).  Obviously I'll take a
> quality hit downscaling and re-encoding for these two things.
> 
>   I have never this before.  I've never even used video editor
> software before, nor have I made a DVD, nor have I successfully
> re-encoded a video file.
[...]
> PROGRESS
> 
>   I have been able to copy the encrypted TiVo file to my PC via HTTP.
> I have used "tivodecode" to decrypt.
> 
>   The file(1) command calls it "MPEG sequence, v2, program multiplex".
> 
>  It plays in mplayer, Totem, and Xine.  VLC seems to load it, but then
> doesn't actually play anything.  It plays it on the Windows side of my
> computer, though, so I think this might be my configuration in Ubuntu
> or something.
> 
> mplayer's text output includes the remarks:
> 
> 	MPEG-PS file format detected.
> 	VIDEO: MPEG2  1920x1080  (aspect 3)  29.970 fps  19000.0 kbps (2375.0 kbyte/s)
> 	AUDIO: 48000 Hz, 2 ch, s16le, 384.0 kbit/25.00% (ratio: 48000->192000)
> 
> PROBLEMS
> 
> >> avidemux <<
> 
>   avidemux will attempt to load it, if I let it create an index when
> prompted.  Takes about 3 minutes.  If I attempt to play it, I get a
> GUI message "Trouble initializing audio device", and xterm message
> "Error setting format" (twice).  If I click OK, it will play without
> audio.  Appears slightly "jerky".  If I go into prefs and change from
> ALSA to OSS, I can get audio that is very choppy and broken up, and
> appears to cause additional video "jerkyness".  Same if I start
> PulseAudio and try that.
> 
>   I can select start and end points, and "Save" them to a new file.
> New file will play as before, with audio, even.  However, it seems to
> loose the ability to move forward/backwards in the video -- players
> either refuse the option, or crash.  mplayer output includes:
> 
> 	Badly interleaved AVI file detected - switching to -ni mode...
> 	AVI: Missing video stream!? Contact the author, it may be a bug :(


So I presume this means avidemux transcoded the clip to an avi. I swear
it supports simply cutting w/o having to re-encode the video, but I
could be mistaken. To be able to make a DVD that will play in a commercial
DVD player, you want to stick to mpeg2. Something else you might consider
trying:

http://www.gopchop.org/

-- 
Jarod Wilson
jarod at wilsonet.com