[Mjpeg-developer] Re: mjpegtools (fwd)

[Roman H. <ro...@ma...>]

On Tue, 26 Mar 2002, Gernot Ziegler wrote:

> I see...
> one possibility I see would be to record to the internal YUV-stream format
> directly. But lavrec can't do that, and it has no clue about the YUV
> format (yet).
> 
> You see, lavrec comes from the MJPEG-world (= hardware compression), and
> that's why we never thought about anything like that before.
> 
> Mail to the video4linux-mailing list, I guess they can help you better.
> 
> Maybe there is an uncompressed nuv-format ? Check out the nuvtools
> http://mars.tuwien.ac.at/~roman/nuppelvideo/
> 
> Have a look at RTJPEG (http://www.ee.up.ac.za/~justin/bttv/). Try to
> record with it, maybe that helps ? (but it's incompatible I think we have no reader for it)
> 
> sorry for not taking your question seriously at first ! :-)
> 
> Servus,
>   Gernot
> ---------- Forwarded message ----------
> Date: Tue, 26 Mar 2002 10:34:46 -0800
> From: Chris Jantzen <ch...@ma...>
> To: Gernot Ziegler <gz...@ly...>
> Subject: Re: mjpegtools
> 
> On Tue, Mar 26, 2002 at 08:32:09AM +0100, Gernot Ziegler wrote:
> > > Is it possible to get a --no-encoding option? My recorder does not
> > > have enough CPU power, and I'd like to recode somewhere else...
> > You won't have enough harddisc bandwidth to record any reasonable
> > resolution ... that's why hardware compression was introduced ;)
> >
> 
> 
> I only want 320x240x24x15fps. That's only around 3MB/sec even my
> old Seagate Hawk can do that, not to mention the RAID's on the server.
> Even 30fps would only be about 6MB/sec -- and my RAID's can get 10MB/sec
> under load.


if your computer is faster than 233 MHz and has MMX you can use
NuppelVideo with RTJpeg compression, if your computer is slower
you can also use NuppelVideo's "nuvrec" tool with the -r (I420 not
RGB) and maybe also with -N option, but there is no way to set the fps
with nuvrec, if it is PAL you will get 25, if it is NTSC you'll get
29.97 fps.

i have a user with a P160MMX@205, who can capture with nearly no
framedrops at 320x240x29.97 with RTJpeg compression

tell me how fast your cpu/computer is and if it (or what) worked 
anyway ...

you can also try the "NVrec" tool by Justin Schoeman or the
"vcr" tool by Bram Avontuur; maybe you can capture with
this tools, but i don't know if the support YUV4MPEG[12] which
you need if you are going to encode it with the very excellent
"mpeg2enc" by Andrew Stevens.

hth, and good --capture-- luck

-- 
mfg Roman
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Roman HOCHLEITNER              ro...@ma...
student at the Vienna University of Technology AUSTRIA
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