[MEncoder-users] new doom9 codec comparission (submission)

[Corey Hickey]

On Wed, December 14, 2005 23:02, Rich Felker wrote:
> On Wed, Dec 14, 2005 at 07:52:34PM -0800, Corey Hickey wrote:
>>>
>>> Yeah, that does happen sometimes. I'm temporarily mirroring the
>>> attachments (with zip file extracted) at:
>>> http://fatooh.org/files/doom9tmp/attach/
>>>
>>>
>>>> Last but not least, I initially started reviewing with the VMR9
>>>> renderless renderer in MPC, but found that both Theora and Snow
>>>> (incidentally both decoded via ffdshow, where the rest of the codecs was
>>>> decoded by ateme's filters, plus AviSynth is decoded by the Helix YV12
>>>> codec) were discolored,
>
> I'm confused... something other than lavc was used to decode lavc when
> doing the quality tests? If so, that will *OBVIOUSLY* make lavc look bad
> due to tiny differences in the idct implementations. The only way to do a
> fair comparison for any codec is to use the exact same idct for decoding as
> the one that was used for encoding.
>
> Can you get doom9 to clarify this, if you're not already clear on it?

I missed that when I read the paragraph last time, but I'm CC'ing Doom9
right now so he can respond. I'll continue relaying replies to the list.

> IMO
> this could be the reason he doesn't think lavc is good, if he's looking at
> single screenshots and zooming in real close. See the discussion recently
> on the ffmpeg lists regarding the same bad quality with xvid when decoding
> using lavc's default idct, or the discussions of it on multimedia.cx.

-Corey