[MEncoder-users] lavc or xvid

[RC]

On Tue, 4 Sep 2007 16:08:40 -0700
Phil Ehrens <phil at slug.org> wrote:

> Eek! nr=300?! Alright, I admit it... I reported the same thing
> once (or twice). If the source genuinely has significant gaussian
> noise, nr=300 can perform miracles... HOWEVER, if you are starting
> with good clean source (like a well-made dvd), nr=10 to nr=30 is
> more realistic.

Almost every DVD I've seen has significant noise, and nr=300 helps a
lot (and I've done several visual and PSNR tests to demonstrate that).
That even goes for the newest digitally-recorded films. The few DVDs
that don't have noise really stand out as unusually clear (appearing
almost fake or cartoon-like), and in most cases, was a direct result of
heavily denoising before encoding.

> These numbers are for 2-pass encodes. If you are doing single-pass
> encodes, hqdn3d will behave much more sanely than nr. But if you
> are doing multi-pass, nr will be better on all live action. Anime
> seems to really love hqdn3d, however.

Unless it's extremely noisy material, I wouldn't use hqdn3d at all. With
default values, it causes blockiness, fades color, and leaves a very
noticable trail behind objects in motion. (the latter seriously disturbs
me). I didn't mind 2:1:1, but at such low values, there's little
benefit to denoising at all.