[PD] Codecs in Gem (again!) & ffmpeg

Zachris Trolin z at hidekultur.com
Thu Sep 1 00:17:53 CEST 2005


A bit late (after all the nice answers) but I have encountered the same
problem, the question of what codec to chose for linux compatibility, in
my case where the mastering is done on a Mac.  As I understand it a good
choise is to use MJPEG(motion jpeg), and everything will be fine and
compatible for linux. I haven't relly understood what photo-jpeg actully
is(apple specific?) but both DV and MJPEG are cross platform and well
defined. Using them is quite safe...

/my to cents...



mån 2005-08-29 klockan 11:23 -0400 skrev B. Bogart:
> Hello all, sorry for the cross-posting,
> 
> Back to the old codec issue here. I was hapiliy working with photo-jpg
> compressed quicktime files for the last couple years. Now I'm working on
> an installation that I'm aiming to make using only open-source software.
> 
> My "orginal" footage is a sequence of 300,000 jpeg frames (80% quality)
> And all I need is a video file that matches the jpg quality of the
> frames, and most importantly is seekable and loadable in Gem.
> 
> So what I want to do is create a quicktime file, using photo-jpeg as the
> codec. Simple eh? hmmm.
> 
> My first try was:
> 
> ffmpeg -i %d.jpg -sameq -vcodec ljpeg output.mov
> 
> Which created the file fine (where, FYI, quicktime pro died miserably)
> but was very big (which is ok) but I could not get vlc,mplayer,totem to
> load it. ffmpeg printed something about "MS style codec tag" when
> creating the file. so I also tried:
> 
> ffmpeg -i %d.jpg -sameq -vcodec mjpeg output.mov
> 
> which did about the same thing, so I gave up on quicktime and tried a
> couple AVIs:
> 
> ffmpeg -i %d.jpg -sameq -vcodec mjpeg output.avi
> ffmpeg -i %d.jpg -sameq -vcodec ljpeg output.avi
> 
> A little better, many of my Gem decoders loaded the file, but not a
> single one was able to make it seekable, I tried all the decoders... all
> return -1 frames.
> 
> So right now I'm building a mpeg2 to try out, though I know decoding is
> going to be less efficient.
> 
> So my final questions are:
> 
> 1. What codec should I use for 300,000 frames (14GB or so) and is well
> suited to build from jpg frames? What container?
> 
> 2. How can I create the [answer to #1] using ffmpeg or some other linux
> land app?
> 
> Thank you!
> 
> Oh and Johannes, I do have the v4l_compat module loaded, so I don't know
> why xawtv reads my v4l2 video stream but Gem does not. Any ideas?
> 
> <B>
> _______________________________________________
> PD-list at iem.at mailing list
> UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list





More information about the Pd-list mailing list