Re: MPEG encoder

[madsdyd@challenge.dk]

On Tue, 13 Jan 2004, Gregor Mückl wrote:

> > Please consult http://mjpeg.sourceforge.net/ and clarify this - I will
> > greatly appreciate that.
> >
> 
> Yep, mjpeg is "Motion JPEG", a format where each frame is a compressed JPEG 
> image. This differs a lot from MPEG. 

Yes, but, I believe this is historically. Here is a snippet from the 
mpeg2enc tool that is part of the mjpegtools package:

        mpeg2enc is heavily enhanced derivative of the MPEG Software Simulation
        Group's MPEG-2 reference encoder.  It accepts streams in a simple  pla-
        nar  YUV  format "YUV4MPEG" produced by the lav2yuv and related filters
        (e.g. yuvscaler(1)) from the mjpegtools(1) package.  A  output  plug-in
        to  the  mpeg2dec(1)  MPEG  decoder  is  available to permit its use in
        transcoding applications. The encoder currently fully supports the gen-
        eration  of  elementary MPEG-1, progressive and interlaced frame MPEG-2
        streams.  Field encoded MPEG-2 is also possible but  is  not  currently
        maintained or supported.

Reading the website and man pages for the different tools definitively 
leaves me with the impression that mjpegtools produce both mjpeg and 
mpeg{1,2} streams. 

I would like to know if I am wrong.
> 
> And the mpegtools I mentioned *do* exist as an entirely different package. I 
> just don't have an URL right now. It's a project of the Berkley University 
> IIRC.

I think part of this package has been integrated into mjpegtools.

I may very well be wrong though.

> However, a short glance at the mjpegtools homepage shows that they seem to be 
> able to handle mpeg streams in some way or another. But I haven't understood 
> in what way (it's 2 o'clock in the morning and I actually belong to bed now).

I know the feeling ;-)

Mads

-- 
Mads Bondo Dydensborg.                               madsdyd@challenge.dk
Value your freedom, or you will lose it, teaches history. "Don't bother us
with politics," respond those who don't want to learn.

        - Free software proponent, Richard M. Stallman