Analogue artifact estimation
[email protected] Sun, 1 Sep 2002 09:54:03 +0100
| Newsgroups | gmane.comp.multimedia.ogg.tarkin.devel |
|---|---|
| Message-ID | <[email protected]> |
Hi, I originally posted these ideas to the Theora developers list, but they suggested that this list might be more appropriate, (I thought that the Tarkin project had died off :-) ), so here goes: > Hi List, > > Just batting a few ideas around here, but would it be possible to > include in to the codec, estimation for common video artifacts that > occur in the analogue world? > > For example, anything that's gone through a composite stage will > likely have dot-crawl and false colour - if we can recognise this > effect in the encoder, we can treat it as a special case. > > Other artifacts that come to mind are: > > * 3-2 Pull down > > * 30/25 and 25/30 FPS conversion artifacts > > * Dropouts, (both noisy, a-la VHS, and solid bars, a-la BetaSP, (which > I believe halves the chroma resolution - can we possibly take this in > to account as well?) ) > > * Stobe effect of a CRT filmed by a different scan-rate camera > > * Colour changes in multi-layered painted cel animation, (where a > character is, say, talking, and they repeatedly add and remove a cel > from the top layer, their face flashes bright and dark :-) ) > > Infact, existing video compression codecs do a *terrible* job of > encoding hand painted animation, especially anime, despite claims by > well known studios that it is not an issue. Good motion estimation to > compensate for poor registration of animation would be worth > investigating. > > I think that the problem with all codecs to date is that they are > designed to compress perfect material originating directly from a > camera. In my opinion, the above *analogue* artifacts are what give > the digital codecs a hard time. > > I'd be very interested on any comments on these points. > > John. --- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/ To unsubscribe from this list, send a message to '[email protected]' containing only the word 'unsubscribe' in the body. No subject is needed. Unsubscribe messages sent to the list will be ignored/filtered.