Talk:MPEG-4

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Unreliable[edit]

I removed the link http://www.theinquirer.net/?article=29679 from the bottom section because it seems to be having persistent redirect errors. I replaced it with a link from an "engadget.com" page, which is not a high quality link, but the best I could find in 5 minutes (my allotted time for such things). Please feel free to replace it, or put it back if/when the theinquirer.net link is healed.

Tzf 20:32, 7 April 2006 (UTC)

The link seems to work for me, but I've added a more interesting one so if the original one is unreliable, we can use yours and this new one. Stephen B Streater 22:06, 7 April 2006 (UTC)

Hinting[edit]

I'm working on a website in which we have a choice of viewing MPG files or MP4s. When implemented the same way, however, the MPG files stream, while the MP4 files wait for the entire file to load. See example here: http://www.proimagestudios.com/newsite/movtest

I used Cleaner 6 to compile the MP4, and was wondering if there was a setting or something I could change to make the MP4 stream in the same way the MPG did.

Thanks, Gregory Gritmon www.gregorygritmon.com GSquaredDesign@aol.com


Hi Greg. mp4 files stream really well. You need to open the files in Quicktime Pro & export as 'Hinted Movie' to enable them to stream (this is presuming that your other setting are correct. Try by passing Cleaner 6 with a single file first.

Cheers

James Frameline.tv


You can generalize "Hinting". Quicktime is not the only tool out there that does hinting, and of course, Quicktime does not guarantee that MPEG-4 elements not natively supported by quicktime (such as BIFS) are passed through to the output. Envivio makes some products that are capable of hinting, but they're probably too damned expensive ;^) Tzf

Licensing section[edit]

MPEG-4 is patented proprietary technology. This means that, although the software to create and play back MPEG-4 videos is easily available, a licence is needed to use it legally. I wonder if something should be mentioned about who owns MPEG-4, and how to license it. In particular, MPEG Licensing Authority can license some of the patents required for MPEG-4 visual (audio is more complex). Unfortunately, the one stop shop idea is currently open to doubt: this article claims that AT&T is suing companies such as Apple over alleged MPEG-4 patent infringement. Stephen B Streater 12:20, 18 February 2006 (UTC)

Proposed wording[edit]

MPEG-4 is patented proprietary technology. This means that, although the software to create and play back MPEG-4 videos may be readily available, a licence is needed to use it legally. Patents covering MPEG-4 are claimed by over two dozen companies. There is no simple way to license MPEG-4, but the MPEG Licensing Authority can license patents from a wide range of companies required for MPEG-4 visual techniques (audio is licensed separately). A one stop shop is currently not possible: this article claims that AT&T is suing companies such as Apple over alleged MPEG-4 patent infringement. This AT&T action against Apple illustrates that it is hard to know how many companies have patents covering MPEG-4. Stephen B Streater 14:33, 27 February 2006 (UTC)

Added this in with a couple of refinements. Stephen B Streater 19:09, 2 March 2006 (UTC)


Part 2 and Quicktime[edit]

The article implies that SP and ASP are the only profiles of MPEG-4 Part 2 I however I know the following exist:

  • Core
  • Main
  • N-bit
  • Advanced Coding Efficiency
  • Core Scalable
  • Simple (SP)
  • Simple Scalable
  • Advanced Real Time Simple
  • Advanced Scalable Texture
  • Advanced Simple (ASP)
  • Fine Granularity Scalable

Ref: http://www.m4if.org/resources/mpeg4userfaq.php#ArbitraryObjects

The MPEG-4 Part 2 article mentions 21 profiles. Because of this I think the claim that the 5G iPod supports all of part 2 may be incorrect. I'd like to see a citation that it supports all 21 profiles.

--70.39.108.127 05:30, 19 June 2006 (UTC)

Nice find. If this iPod supported all of part 2, it'd be the only device to ever do so! Personally I suspect many of the profiles have never been implemented (and never will be), but I've never attempted to verify this suspicion... Snacky 00:31, 20 August 2006 (UTC)

Very confusing[edit]

Lots of words, very little explaination. This article should be made much easier for people researching before buying an mpeg-4 player etc. The article should begin with a conscise definition of mpeg-4, continue onto what it encapsulates, file formats, comparison with other codecs. If I have made technical mistakes, its because this article is misleading :P Chris 05:28, 27 September 2006 (UTC) I agree, I can hardly make head nor tail of this article. 218.214.138.11 07:46, 11 July 2007 (UTC) Talk about confusing; the Apple links should be removed because they make it sound as if MPEG4 was developed intimately with Apple Quicktime. This is all very deceptive spin on Apple's part and has no place in an article such as this. I propose to remove them. Freddy011 (talk) 01:29, 20 November 2009 (UTC)

File extensions?[edit]

I'm not shopping for an mpeg-4 player, but I was hoping for some clues on how to recognize an mpeg-4 file. Are specific extensions used? Which? Does the extension matter? Also, can any mpeg-4 codec be used with any mpeg-4 file? If not, why not? —Preceding unsigned comment added by Preserved killick (talkcontribs) 21:16, 16 July 2008 (UTC)

Alternatives section[edit]

The Alternatives section seems far too lengthy and prominent. There's more information in this article on what to use other than MPEG-4 than information on what it does and how it works. Maybe not quite NPOV-violating, but does have the air of an anti-patent troll Slashdotting things up (why wouldn't proprietary options like Windows Media, Real, or QuickTime also be considered "alternatives"?) Maybe the alternatives stuff should be a different article, or maybe it wouldn't be as bad if there were more meat to the article (for example, material on MPEG-4 performance, compatibility, popular uses, history, design theory, etc.). Invalidname Wed Dec 6 02:44:44 GMT 2006

What's next?[edit]

What codec is being planned after MPEG-4? --24.249.108.133 21:47, 27 September 2006 (UTC)

As of 2010, a new video standard is currently being developed under the name of High Efficiency Video Coding (or H.265 or H.264+), designed to succeed H.264/MPEG-4 AVC. However, it'll probably still fall under the MPEG-4 umbrella. In audio, due to lack of demand, most development takes the form of extensions to AAC, with the latest being MPEG-4 SLS (HD-AAC) and MPEG-4 ALS, both of which are still MPEG-4. The other parts of the standard are even more stagnant. C xong (talk) 01:01, 26 May 2010 (UTC)

No inventor/organization's name?[edit]

As far as I know MPEG-4 is by Hong Kong University of Science and Technology.

http://www.ust.hk/~webopa/news/2000_News/news0613.html —Preceding unsigned comment added by 58.153.0.155 (talk) 03:34, 28 October 2007 (UTC)

Read the part that says "agreed upon by the ISO/IEC Moving Picture Experts Group (MPEG) under the formal standard ISO/IEC 14496". The organisation is ISO/IEC. Kegon (talk) 04:22, 16 January 2008 (UTC)

Proposed table[edit]

Does anyone else think it would be a good idea to have a comparison table of the variants of mpeg4 (DIVX XVID H264 etc etc) which would include links, supported resolutions/field rates, data rates, features and codec efficency ? 86.112.239.124 (talk) 15:08, 23 August 2009 (UTC)

DivX, Xvid and H.264 are not variants of MPEG-4 (plus DIVX and XVID are FourCCs). DivX is a company and a brand name, and DivX Pro Codec is a popular MPEG-4 ASP (and AVC) codec made by the DivX company—it is a software implementation of MPEG-4 Part 2. A software implementation is not "a variant". Xvid is an open-source MPEG-4 ASP codec—another software product implementing the MPEG-4 Part 2 standard. H.264 is not a codec or a variant of anything, it is another name for MPEG-4 AVC, that is, the MPEG-4 Part 10 video format (it is not an implementation, it is the specification, the standard). So the comparison would be very confused, as it would compare apples with oranges.
Furthermore, Wikipedia already has the Comparison of video codecs article.—J. M. (talk) 18:28, 23 August 2009 (UTC)

"Improved Coding Efficiency"[edit]

An ATI document provides an interesting graph of quality versus bitrate of H.264 and MPEG-2, which is what is (probably) intended by the statement "improved encoding efficiency" on the lead-in. Would this be suitable, or is a more rigorous comparison required? --Freeone3000 (talk) 17:44, 19 April 2010 (UTC)

That document looks more like a marketing brochure than a technical document. Even though to video people it's blindingly obvious that MPEG-4 provides improved efficiency over MPEG-2, if it needs a citation it'll have to be from a better source. C xong (talk) 00:49, 26 May 2010 (UTC)