Talk:MPEG-4 Part 2

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There seems to be a lot of factual errors in the article. This article is best written by someone who knows the intricacies of video coding. I would do it, if no one else does withing the next one month. I just want to make sure, someone more capable than me take a jab at it.

Great, may I suggest the first error to correct is the WTF-inducing stuff about qpel. It states:
The quarter-sample motion compensation feature of ASP was innovative, and was later also included (in somewhat different forms) in MPEG-4 Part 10 and VC-1. It is considered the most beneficial innovative feature of ASP.
Innovative? Uh, questionable. Beneficial? Who makes this stuff up? Note to whomever wrote this originally: please quit writing sweeping statements ("most beneficial and innovative"?!) about topics you're ignorant of.
ASP's qpel places large demands on the decoder, and in exchange for this, you usually get no improvement in quality at all. It frequently reduces quality. While the idea was kept (and indeed made mandatory) in H.264, its qpel works differently; in particular it doesn't cause such a large speed hit. Snacky 21:24, 21 March 2006 (UTC)

Although less-mentioned, a wavelet-based still image codec is also a part of ISO 14496-2. One can quote it from a place with little copyright trouble. turanyuksel 09:17, 09 April 206 (EET DST)

Contents

[edit] work in progress.

I have started editing this page to correct and enhance the contents. The person who did the entry on H.264 could do a better job here, and so, please feel free to edit the entire content if you see this. thanks... Else I will go through a multi stage edit and make sure the content is good, by the end of the month.

[edit] Profiles

According to http://www.mpegla.com/m4v/m4v-faq.cfm

“ current MPEG-4 Visual Standard profiles... are simple, core, main, simple scalable, N-bit, basic animated texture, scalable texture, simple FA, advanced real time simple, core scalable, advanced coding efficiency, advanced core, advanced scalable texture, simple FBA, hybrid, advanced simple, fine granularity scalable, simple studio, and/or core studio profiles as defined in ISO/IEC 14496-2:2001 [Part 2 Visual dated 2001-12-01], 14496-2:2001/Amd.1:2002 [Studio profile dated 2002-02-01], or 14496-2:2001/Amd.2:2002 [Streaming video profile dated 2002-02-01]. ”

[edit] harmful effect on speed ?

The article says "harmful effect on speed". As a codec has no moving parts, this is ambiguous. Is it the encoding speed ? Decoding speed ? Some other speed ? --Xerces8 (talk) 11:15, 25 November 2007 (UTC)

[edit] Criticisms from users?

I think something in this page should include the reality that XviD is by far the most popular codec of video encoded for p2p transfer —Preceding unsigned comment added by 203.217.94.187 (talk) 12:48, 25 February 2008 (UTC)