[MPlayer-users] PSNR Questions
D Richard Felker III
dalias at aerifal.cx
Sat Feb 15 18:48:53 CET 2003
On Sat, Feb 15, 2003 at 05:32:04PM +0000, Ian wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> D Richard Felker III wrote:
>
> >Huh?? This is nonsense. You can't compare PSNR relative to two
> >different reference 'signals'. When encoding, the source is considered
> >the signal, and the difference between the encoded picture and the
> >source is the noise, so the source has infinite PSNR automatically.
>
> OK, this is the first time I've seen it stated, a formula would be nice
> too, but in any case see below . . .
>
> >Yes, theoretically. Computational issues might make it come out
> >different tho.
>
> Regardless, since in my experience better quality material (ie. the
> originals!) has a lower PSNR than the copies, I can't take it seriously.
> Obviously your experience is different.
How are you measuring the PSNR of the original?? Like I said, you have
to use the same reference to compare PSNR.
Rich
More information about the MPlayer-users
mailing list