Re: [Mjpeg-users] feeding mpeg2enc with many streams simultaneously

[Steven M. S. <sms@2BSD.COM>]

On Tue, 15 Aug 2006, Michael Hanke wrote:

> I have a project (a movie) consisting of many takes. Most of them need their 
> own setting for preprocessing (denoiser, scaler etc) which are very different 
> from take to take such...

> of them, I prepared files 1.mpg, 2.mpg,...,N.mpg. When authoring the DVD I 
> managed for playing these files in order without pausing. Unfortunately, this 
> method works bad. Depending on the hardware DVD player...

	Yes, the "join"/"splice" point between m2v files causes problems with
	some (many?) hardware DVD players.  The symptoms vary in severity -
	some players have a momentary glitch and proceed, other places stutter
	badly, and some stop playing.

> Here comes my question: Is there a nice (automated?) possiblilty to make 
> something like this working:

> (lav2yuv 1.eli | a_long_preparation_pipe_1 ; \
> lav2yuv 2.eli | a_long_preparation_pipe_2 ; \
> .........
> ) | mpeg2enc

	That is precisely what needs to be done.

	This has been talked about several times on the mailinglists in the
	past.  Unfortunately with 17000 messages in the archive it is hard
	to find the answers to specific questions.

	This may be what you're looking for:

	http://sourceforge.net/mailarchive/message.php?msg_id=7061972 

> such that I obtain only one mpeg file?

	Nothing automated exists to create such a script.

	It is not hard to create such a script manually though.   

	Depending on the version of mjpegtools you are using it may be necessary
	remove the YUV4MPEG2 header (that's the first line in a Y4M stream: 
	YUV4MPEG2 W640 H480 F30000:1001 Ip A1:1 C420mpeg2) from all EXCEPT
	the first command.  I think there is code present in the current
	version to do this automatically.  Skipping a line is done with a 
	simple shell function that reads a line into a junk variable that is
	ignored.  THe script in the posting above shows how this can be done.

	Enjoy!

	Cheers,
	Steven Schultz