Re: [libdv-dev] DV decoding performance

[Charles 'B. K. <kr...@ac...>]

The profiler is gprof.  The documentation for it is pretty good.  

At the Intel Developer Forum, I saw a demo of real-time transcode from
DV to MPEG-2.  The vendor was Ligos (www.ligos.com), and of course, it was
Windows based.  Their product was pushing hard on a P4.

It will take a lot of engineering to to do the same with libdv and a
Linux mpeg encoder (mp1e?).  You would need to spend a great deal of
time optimizing code, as in you need to become a world-class expert at
MMX and codec optimization ;-)

(I'm only half joking).

Alternatively, you probably could do it easily enough on a multi-processor, 
where one CPU does capture and DV decode, and the other does MPEG encode.

-- Buck


Rodney Schneider <ro...@bi...> writes:

> Hello again!
 
> Thanks for the info.  The front-end/display performance is not that
> important to me.  I want to write some software that will allow me
> to use my DV camera to create live webcasts (similar to cheaper web
> cams, but with better quality video) so that when I put on partys,
> friends who are in other countries can watch what is happening from
> home.

> To do this, I suppose I would need to decode a DV stream into YUV
> raw video and PCM raw audio and simultaneously encode the data into
> MPEG or another suitably compressed format for transmission.

> I am wondering how close to real time the actual decoding of DV is,
> without displaying it.  What profiler do you recommend for me to
> use, and could you give me any useful tips on what to look for?  I
> am an experienced Java programmer, but my C skills are a little
> rusty.

> Thanks again,
> 
> -- Rodney