[vdr] Re: System requirement?

[Andrei Boros <andrei@srr.ro>]

Gregoire Favre wrote:
> 
> > On A P3/933 with the windows DivX4, encoding of an AVI file 480x360x25
> > goes at 14fps at most.
> 
> Well, that's already quiete impressive, just think if your P3 would be
> 2000, you got about 28, and a P4 even more...
Keep in mind that this is a recording in AVI file on disk and it is
coded with HUFYUV lossless codec (see links page from
www.virtualdub.org) at about 10GB/hour. Decoding of the HUFYUV AVI is
excellent and very fast, while MPEG2 playback, purely in software, like
with FLASK, still leaves a lot to be desired.

> Well, on my P3@450 using xmga extension of my G400 it took my about 40%
> of CPU to watch a DVD... but without xmga, should need more CPU, would
> be nice if one could use such extension for mencoder under linux ;-))
Does the G400 have hardware DVD playback capability ?

> Regarding what you could do with your P3@933, that's should be enough???
See my additional comments on that.

I've seen movies captured with ATI All In Wander 128 that has a hardware
MPEG2 encoding capability on a P3/800 being converted to a low
resolution divx at 320x240 with all decoding settings set to
fastest/lowest quality in FLASK at about 10fps. I'm scared to think how
long it would have taken to use the DVD resolution in the output DivX.

> Thanks for your answer, I think up to now, for me the best solution is
> to backup movies on multi-CD-R, in VDR format, CD-R are so cheap...
With my ATI All In Wander I usually do the following : 
- record a movie from TV/cable on a VCR. I have a Panasonic NVF-70 (top
of the line in 1990, in excellent condition) .
- record the movie into the PC via the ATI card using HUFYUV codec and
multisegment capture at 480x240x25 with 22/16/m sound. This takes about
15-18GB per 2 hours of movie
- Use virtualdub to compress the movie. I use some filters to clean up
the image and make it easier for the divx codec to work (not loose too
much bitrate on noise). Usually temporal cleaner, 2D cleaner and levels.
The add resize to 480x360 and compress it to about 700kbps, sound
MP3/32kbps (@22/16/m)
- On my previous P2/350, a 90min movie took about 16hours to compress.
- On my current P3/933 it takes 5-6 hours
- If I don't use any filters and no resize, transcoding goes as fast as
14fps, but average of 12, but this is not usable, as the aspect ratio is
wrong.
- I gave up on-the-fly divx compression when recording (worked great
with P2/350) because the increase in horizontal resolution with vertical
interpolation gives a huge improvement on image quality, and
postprocessing filtering helps even more.
- then I simply write it to a CD. Actually I use a bitrate calculator so
that I set the divx compressor such that the movie will fit exactly onto
a CD, adjusting a bit more or less around 700kbps to obtain this.

Since I still can't use vdr (drivers 0.8.2, vdr 0.7.2 won't compile, I
don't have vdr 0.7.1), I still can't record from my DVB card. :(


Hope this helps.

-- 
ing. Andrei Boros
mailto:andrei@srr.ro / +40-1-303-1865
Centrul pt. Tehnologia Informatiei
Societatea Romana de Radiodifuziune