2006 codec comparison

[vlada]

Doom9> Thank you very much for the new shoot-out. But I have a question though. Why didn't you use VBR sound for the movies? It really makes sense here IMO. I think it would give some more points to MP4 codecs because of overhead.

[stephanV]

Personally, I don't get the whole dealing with audio and containers. For me it is too irrelevant for a test that is apparently and should be about comparing video codecs. I know this is for achieving a "realistic" back-up scenario, but forgive me, what in earth's name is that? Is targeting 1 CD still the most realistic scenario these days? Is putting DivX in mp4 a realistic scenario? Is using 2ch LC-AAC a realistic scenario? Sure they are all realistic in the sense that it is possible to do this, but is it realistic in a way that these are commonly used methods? That would at least seem highly doubtful to me.

Just let all codecs target the same bitrate and let people themselves decide how exactly they want to back up video. That would confess of much more realism. Muddling with audio and containers only substracts value of the test. Or perhaps it should be renamed to "back-up comparison"...

[Doom9]

Let me just cut you short: everybody who wants to bitch about containers and methodology can go somplace else or faces rule 16. Make your bed and sleep in it.
And for all the know it betters, it is impossible to work with the same container everywhere.. there's always a reason why you can't put codec X into container Y or why you can't work with raw streams.

[Doom9]

here's your one chance to make your voice heard: http://forum.doom9.org/showthread.php?t=104245

[Xayd]

I sent an email to the address the dirac team used to sign up here.. I hope that'll work out. Can you PM me the address so I can verify it's the proper one?

@zambelli: Well, if you have access to a non corrupted HD MPEG-2 source of say Matrix3, I'd definitely be interested.. same goes for the other movies that'll be in the comparison. As it so happens, I live in Europe and our HD situation is pitiful.. and due to the lack of HD sources on my part (I'm not interested in test clips, I need the real deal - full length movies), how could I possibly to do a HD test?

the best HDTV source for such a comparison would be the Gladiator broadcast that was on BEV satellite in canada. it's reference material quality. not even any blurring or pixelation in fight scenes, for all intents and purposes, perfect ;).

and it has good scenes for codec comparison, imo. there's the panning scene at the beginning with flaming arrows being shot into that forest, and another panning scene when they first get to rome and are riding up to the coliseum. also the combat scene with the tigers in the arena floor.

most HDTV these days suffer from down-rezzing and rate-shaping from the cable and satellite broadcasters, so quality is very hit and miss. this broadcast is one of the few flawless ones out there. it's an older broadcast that was done at near-full bitrate before down-rezzing and bitrate shaping became widespread.

if you happen to have access to a premium newsgroup service, it looks like there was a re-mux of this recording put up with a french soundtrack about 20 days ago. newzbin search (http://www.newzbin.com/search/query/p/?q=gladiator+hdtv&Category=-1&searchFP=p)

it's about ~25 gigs for the whole movie.

as for xvid in such comparisons, i think it would actually be surprising to most people how well xvid performs. i encoded the above mentioned movie resized to 720p with a bitrate considered by most to be too low for preserving HD quality (below 4000 kbps, to fit on a DVD-R), and it still looks flawless. the quality lost when encoding to xvid is actually less than the quality lost by software player (libmpeg2 without post processing) resizing to 720p on the fly during playback.

imo, with high quality HD sources, you get to a point where real-time resizing is actually WORSE than something coming out of avisynth that is "properly" resized and re-encoded. look at the below screen captures from this source...

http://img454.imageshack.us/img454/1886/gladiator7zz.th.png (http://img454.imageshack.us/my.php?image=gladiator7zz.png)

one is my xvid encode, the other is the HDTV source file simply played back at a 1280x720 resolution. you would think that the slightly blurred image on the bottom is my xvid, right? it's actually the other way around, the frame on the bottom is the transport stream, the sharper frame on the top is my 4000 kbps xvid encoded with the sharp-mpeg matrix that autogk uses. why is the result what it is? that's arguable, but the result is right there in black and white, it is what it is.

besides the space-saving, i think it's actually feasible that people might re-encode their HD captures anyway, simply because playback software (and hardware) is unreliable. real-time resizing is poor, and software deinterlacing is also poor, on average. so deinterlacing in avisynth along with resizing to the exact pixel for pixel resolution of your display could actually be preferable for quality because playback software/hardware causes more quality loss than re-encoding does.

so yes for codec comparison resolution difference is just a matter of math, but when you get into playback issues that many displays and playback devices/software have, there's more to consider than the simple math of storage space and quality at a certain bitrate. for these reasons HDTV comparison is definitely worthwhile, imo.

[siddharthagandhi]

I suggest the Sony AVC Codec and the Mainconcept AVC codec...both of which found in Sony Vegas.

[baer999]

When will the new codec comparison start or will be released?

[karasu]

good question

[Snakekick]

but no answer

[mdoubledragon]

Yawn! Yawn! So much for the shoot out:rolleyes: