Hi,

0n 07/03/[EMAIL PROTECTED]:48 Torsten Mohr told me:

> i capture some TV broadcasts with my Hauppauge PVR350 and the ivtv driver.

AFAIK PVR already delivers a perfect mpeg2 program stream.

> I then cut those sequences with "avidemux2" and write them as AVI, settings
> video: MJPEG, audio: WAV PCM.

*Huch*, mjpeg != mpeg
         ^

mjpeg is more or less a jpg images slideshow running fast enough to
let you think it's a movie ;). Every single picture is stored in
mjpeg making it probably good for cutting but it's a waste of bits.

That format has nothing to with mpeg used for DVD. mpeg2-ps as used
on dvd only stores every 15th picture (I-frame) in total and the
other pictures just describe the differneces to this "master frame".
It's probably somewhat harder to cut it, but a lot better in saving
bits.

The stream you receive from your 350 is mpeg2-ps, just that sort of
thing you need for dvdauthoring. Use avidemux just for cutting and
dvdauthor to get it to dvd. transcoding shouldn't be envolved in
your production process.

> I try to convert this output to MJPEG compatible DVD with this command:

There is no mJpeg compatible format for DVD.

> [1]
> transcode -k -i $in -o $out -xlav -yffmpeg,lame -Fmpeg2video -w 4000

mp3 (lame) isn't allowed on dvd, too.

> mplex -o $out -f8 $video $audio

mplex should have warned you as mp3 doesn't meet -f 8.

> Playing the output file with MPlayer works fine, but when i feed it to

mplayer eats almost everything, but your hardwarebox wouldn't

> dvdauthor it complains on every frame:
> 
> WARN: unknown mpeg2 aspect ratio 1
> WARN: Discontinuity in audio channel 8; please remultiplex input
> 
> 
> Playing the DVD on a DVD player leads to missing sound.

For DVD-video mp3 isn't an Option.

> I tried to remultiplex this way:
> [2]
> tcextract -i $in -x mpeg2 > $video
> tcextract -i $in -x mp3 > $audio
> mplay -o $out -f8 $video $audio

s/ay/ex/ ?

> What do i need to do to get DVD compatible output?

Just skip the transcoding step.

> When i use avidemux2 to cut MPEGs on I-Frames i can create DVDs using
> method [2].  But when i cut MPEGs not directly on I-Frame borders
> i need to output AVI (MJPEG, WAV).  Converting this to DVD MPEG fails.

I am not familiar with avidemux, but it should be able to reencode
the sceens around your cutting point to meet specs again. If it
can't don't cut at P or B frames or use a different tool. IIRC there
was a command line tool out there which can cut mpeg2 content
exactly even at P or B frames.

Again there is no need to transcode your content. Dunno if it will
be visible, but you will loose quality be transcoding.

HTH

-- 
bye maik

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