[mythtv-users] how to get direct MPEG2 output

[Ken Bass]

Sam, did you realize that my calculations were for uncompressed data? 

Jelle, someone in the PAL world is probably better suited to tell you what 
they get compressed. In NTSC at 352x480 I get about 1.6GB/hour. At 480x480 
I was getting 2.2 GB/hour.


On Mon, 24 Nov 2003, Jelle Kalf wrote:

> Ok, thanks for the info.
> 
> Btw, I'm running on PAL, 59x720x567x24  .... *eek*
> Checking my caluclations I'd be running at 246GB/Hour. I'd have to be worried as I've only got a 20gb harddrive for now. But with my compression, what should I be thinking of?.. I'll find out soon enough I have to compress a double StarTrek Enterprise show at 20:30 to 22:15 I'll find out soon enough when the spare drive runs out of space...
> 
> (*brain fart* .... I'd better just kill the partitions on it right now and format it 40gb to be safe.)
> 
> Jelle Kalf
> 
> On Mon, 24 Nov 2003 12:56:50 -0500
> Ken Bass <kbass at kenbass.com> wrote:
> 
> > Jelle,
> > You are definitely not running uncompressed. If my *approximation* is correct:
> > Assuming 30 fps, 720 x 480 pixels, 24 bits/pixel:
> > 720 x 480 x 24 x 30 = 248,832,000bps ~ 31MB/sec * 3600secs/hour = 111 GB/hour
> > (74GB/hour at 480x480 which is mythtv default).
> > 
> > I have changed my recordings to use 352x480 which is called 1/2 D1 rate and it
> > is a resolution supported by the DVD standard. From what I understand there 
> > are only two
> > resolutions (in the NTSC world) that DVD supports - 720x480 and 352x480. If 
> > you are playing your DVD's using PC software sometimes those specs aren't 
> > enforced and you can get away with different resolutions but if your goals 
> > is to archive onto a DVD that is the most compatible with a range of 
> > standalone DVD players, I'm thinking only these two resolutions makes 
> > sense. By capturing at these resolutions I don't need to reencode. In 
> > theory you can then cut out the commercials for archiving without having to 
> > reencode. I still have not found a tool that lets me cut out commercials 
> > without reencoding. I've tried a ton of windows and linux programs and most 
> > of them either don't work or they screw up the audio/video sync. I'm still 
> > working on that.
> > 
> > At 11:23 AM 11/24/2003 -0500, you wrote:
> > >On Mon, 2003-11-24 at 09:44, Jelle Kalf wrote:
> > > > Hi,
> > > >
> > > > I tried recording 4:02 minutes of data and it came back to me with 151MB of
> > > > data. I have a PVR250 card which should have instand MPEG2 compression. 
> > > What did
> > > > I do wrong, because it looks like it's just outputting uncompressed data...
> > > >
> > > >
> > > > Jelle Kalf.
> > >
> > >151MB/4 minutes*60 minutes/hr ~ 2.2Gigs/Hr which is what I get with my
> > >PVR 250 and 350 under normal circumstances.  What makes you think this
> > >is wrong?
> > >
> > >
> > >-jose-
> > >
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> > 
> > 
>