MPEG-4 parameters

[vlada]

Hi,
I was asked by a magazine to write an article about playing DivX/XviD on standalone players. I'd like to consult with you some facts, so I won't be spreading any misinformation. I have some question where I'm not sure with the answer.

1) DivX 3.11 is not MPEG-4 compatible, but is very similar to it. It is based on MS MPEG4v3 encoder (beta or final version?). It has no ASP profile futures.

2) The ASP futures are GMC, Q-PEL and b-frames. B-frames and Q-PEL are supported by most players, however GMC+Q-PEL is not usually decoded properly. AFAIK there is no player supporting GMC in XviD.

3) Packed bitstream isn't widely supported, but can be removed without recompression. The support depends more on firmware then on chip-set.

4) Do players usually read MPEG-4 Aspec Ratio information? It should be again related to firmware not to chip-set.

5) DivX 6 has no new futures compared to DivX 5 (except of the new container).

6) DivX 4, 5 and 6, XviD, 3ivX, LAVC and ND codecs are fully compliant with ISO MPEG-4 ASP standard.

7) MPEG-4 AVC (Advanced Video Compression) ads new futures to MPEG-4 ASP. What are the new AVC profile futures? AFAIK there is no standalone player supporting MPEG-4 AVC.

8) There are no players supporting MKV, some do read OGM and MP4 files. Are there any tools which can convert video from MP4 to AVI without recompression? Can MKV with native MPEG-4 video stream be converted to AVI?

9) If I change fourCC code in AVI file, all players supporting DivX should play other MPEG-4 AVIs too. I heard about Sony players not supporting XviD, did anybody try changing FourCC code to DIVX or DX50?

10) In AVI I can have MP3, AC3, DTS and AAC sound. I can't have Vorbis in AVI (in fact yes, but it isn't supported widely). MP4 should only contain MPEG-4 video and AAC audio. AAC isn't usually supported in standalone players and is not supported by recievers at all. Is AAC HE or AAC PS supported in any player?

Could you please tell me if my information are correct? Thank you in advance.

Regards,
Vlada

[Shinigami-Sama]

1) not sure
2)sometimes both are, depends on model, not many<if any> support xvid's 3-point gmc
3)some suport it some don't
4) same as above, though fewer
5)it's only a new extention not container, it puts the stuff in a riff-tree, so it needs to have its firmware updated to access the newer features
6)that depends on setting mostly
7)I read something about a SA with avc support, but I havn't seen any, avc is still rather new
8)there is ONE supporting mvk IIRC, a friend was talking about it, but I'm not sure
9)as long as the codecs are to be dvix complaint they should work, but murphy may nose in from time to time
10).mp4 can can have everything .avi can, player support I unertain of however

[vlada]

Shinigami-Sama> Thank you for the answers.

Does anybody have any idea how to convert MP4 or MKV to AVI without recompression? It shouldn't be a problem to extract the elementary streams from these conatiners, but how do I mux them in AVI?

[dimzon]

1) It's posiible to convert DivX3 into MPEG4 Part2 without recompression (use search)

[Shinigami-Sama]

Shinigami-Sama> Thank you for the answers.

Does anybody have any idea how to convert MP4 or MKV to AVI without recompression? It shouldn't be a problem to extract the elementary streams from these conatiners, but how do I mux them in AVI?
look on the download part of main site

[SeeMoreDigital]

The answers to many of your question can be found by reading the "sticky" (http://forum.doom9.org/showthread.php?t=91616)in the Hardware Players section of the forum.


Cheers

[bond]

Hi,
1) DivX 3.11 is not MPEG-4 compatible, but is very similar to it. It is based on MS MPEG4v3 encoder (beta or final version?). It has no ASP profile futures.yes

2) The ASP futures are GMC, Q-PEL and b-frames. B-frames and Q-PEL are supported by most players, however GMC+Q-PEL is not usually decoded properly. AFAIK there is no player supporting GMC in XviD.i wouldnt call qpel and gmc "futures", after all they are here for years already in xvid

xvid uses 3 warppoint gmc which no players supports
divx5 uses 1 warppoint gmc which some players support

another asp feature which is very powerful is custom quant matrices, eg available in xvid

3) Packed bitstream isn't widely supportedsupported where? when you talk about playback you are wrong

but can be removed without recompression. The support depends more on firmware then on chip-set.yes

5) DivX 6 has no new futures compared to DivX 5 (except of the new container). wrong

6) DivX 4, 5 and 6, XviD, 3ivX, LAVC and ND codecs are fully compliant with ISO MPEG-4 ASP standard.yes

7) MPEG-4 AVC (Advanced Video Compression) ads new futures to MPEG-4 ASP. What are the new AVC profile futures? read the avc sticky

AFAIK there is no standalone player supporting MPEG-4 AVC.[/QUOTE]depends on what you call a standalone player
hardware players, like the sony psp and the xboxmediacenter support it

8) There are no players supporting MKV, some do read OGM and MP4 files.i doubt there are players supporting ogm

9) If I change fourCC code in AVI file, all players supporting DivX should play other MPEG-4 AVIs too. I heard about Sony players not supporting XviD, did anybody try changing FourCC code to DIVX or DX50?wrong
every mpeg-4 player supporting specific mpeg-4 features supports any mpeg-4 stream using these features no matter what encoder was used

10) In AVI I can have MP3, AC3, DTS and AAC sound. I can't have Vorbis in AVI (in fact yes, but it isn't supported widely).yes

MP4 should only contain MPEG-4 video and AAC audio.wrong
read the mp4 faq

AAC isn't usually supported in standalone players and is not supported by recievers at all.wrong
every hardware player supporting .mp4 usually supports aac too (eg all nero players)

Is AAC HE or AAC PS supported in any player?he- and ps-aac is backwards compatible, any aac player can play them

[Elic]

vlada >> The ASP futures are GMC, Q-PEL and b-frames
bond > i wouldnt call qpel and gmc "futures",
I think maybe vlada mistyped "futures" instead of "features"?

[bond]

vlada >> The ASP futures are GMC, Q-PEL and b-frames
bond > i wouldnt call qpel and gmc "futures",
I think maybe vlada mistyped "futures" instead of "features"?yep, might be :)

[vlada]

bond> Yes, this is what I did. Sorry for the confusion.
Thank you all for the replys. Just a few more things:

AAC-HE (AAC SBR) is backwards compatible with AAC, but with a quality loss. It should be the same as MP3 and MP3Pro, the SBR part won't be decoded. Or am I wrong?

The SiGMATek XM-380 Pro should support OGM. Anybody tried it?

According to point 9, I think I said the same as you did, bond. Maybe it's again caused by my weak English...

Regards,
Vlada

[SeeMoreDigital]

AAC-HE (AAC SBR) is backwards compatible with AAC, but with a quality loss. It should be the same as MP3 and MP3Pro, the SBR part won't be decoded. Or am I wrong?The theories behind the two formats are very similar!

AAC-HE can be played in an non AAC-HE device. Likewise MP3pro can be played in an non MP3pro device... But obviously without gaining access to the SBR element!

The SiGMATek XM-380 Pro should support OGM. Anybody tried it?There are a few other devices that are reported to support the OGM container... but they only capable of playing "audio" streams in .OGM. Not audio and video!


Cheers

EDIT: OGM playback (OGG audio only in OGM) is reported but not official AFAIK

[vlada]

look on the download part of main site
I did, but I haven't seen any tool, which can mux elementary MPEG-4 video stream in AVI.

[SeeMoreDigital]

I did, but I haven't seen any tool, which can mux elementary MPEG-4 video stream in AVI.For de-muxing MPEG-4 SP/ASP streams out of the .MP4 container you could use GUI based tools such as YAMB or mp4UI. And then AVI-mux to re-mux the stream into the .AVI container ;)


Cheers

[bond]

There are a few other devices that support the OGM container too... but they only capable of playing "audio" streams in .OGM. Not audio and video!so they are plain ogg vorbis players with no explicit support for .ogm

[SeeMoreDigital]

so they are plain ogg vorbis players with no explicit support for .ogmNot sure.......

The new Packard-Bell DVD-DivX 450 Pro, clearly states "OGG Audio" playback (and displays a OGG audio logo... very posh). Same too, with some of the KiSS players.

But over on the Zensonic Z500 forum, the following topic recently appeared: -

http://www.z500series.com/forum/index.php?showtopic=106


Cheers

[bond]

ogg is not the same as ogm!

[SeeMoreDigital]

ogg is not the same as ogm!Yes I realise that...

I can only go by some of the reports I've seen whereby some people have mentioned they were able to play OGG audio streams within the .OGM container as well as .OGG

I read on a forum somewhere that a couple of people with Lite-On LVD-2002 owners tried, and were able to do this.

On a different note. With any luck we should soon have a stand-alone player that supports Matroska :eek:


Cheers

[bond]

I can only go by some of the reports I've seen whereby some people have mentioned they were able to play OGG audio streams within the .OGM container as well as .OGGwell when people talk about "ogg audio" they normally mean vorbis, but its not really correct to say "ogg audio " as ogg is a container like avi and can therefore be used for storing different coding formats (eg officially ogg supports vorbis, flac and speex audio already)

the point is that vorbis is stored exactly the same way in .ogg as in .ogm, therefore for a player supporting only ogg vorbis an ogm file with vorbis audio simply has a wrong extension, but he might handle it anyways

On a different note. With any luck we should soon have a stand-alone player that supports Matroskathere were always rumours around which never became true. till i see it i dont believe it

[yaz]

AAC-HE (AAC SBR) is backwards compatible with AAC, but with a quality loss. It should be the same as MP3 and MP3Pro, the SBR part won't be decoded. Or am I wrong?it's maybe only some 'linguistics' again, but as u were prompting that he-aac would be worse than lc-aac (or non-he-aac) and the same for mp3-pro and mp3. if so, u're definitely wrong.
if u mean that playing he-aac on a non-he-aac-capable device would give lower quality then u're right.

'he' means 'high efficient' (technique). by applying it the same quality may require less space, or the same space may hold higher quality. it is the theory.
quality, as such, depends highly on the implementation (so, on the perfection of the tool for encoding) and on the settings (so, on the perfection of the person using the tool)

the bests
y

[SeeMoreDigital]

well when people talk about "ogg audio" they normally mean vorbis, but its not really correct to say "ogg audio " as ogg is a container like avi and can therefore be used for storing different coding formats (eg officially ogg supports vorbis, flac and speex audio already)

the point is that vorbis is stored exactly the same way in .ogg as in .ogm, therefore for a player supporting only ogg vorbis an ogm file with vorbis audio simply has a wrong extension, but he might handle it anywaysI would be most grateful if you could please e-mail me (or post here) some encode samples (from the same source) with all the possible file extension/container alternatives?

there were always rumours around which never became true. till i see it i dont believe itAgreed...

However, I am able to confirm that Zensonic and Matroska have started discussions :)


Cheers

[Doom9]

there were always rumours around which never became true. till i see it i dont believe itword!
The only bet I'd make on future standalone support is AVC in MP4. Nero will make that happen if the chips finally become available, and we can jump on the bandwagon with x264 & mp4box.

[bond]

However, I am able to confirm that Zensonic and Matroska have started discussionsyep, i know. its not the first time that hardware player manufacturers have contacted the mkv guys, still till now nothing came out
maybe this time its different, dunno...

about flac, speex aso in .ogg, a possible way to create those would be either with the flac and speex encoder or with illiminables dshow filters

[SeeMoreDigital]

about flac, speex aso in .ogg, a possible way to create those would be either with the flac and speex encoder or with illiminables dshow filtersAs and when I get players to test I don't mind trying any file with it. I also don't mind sending people files to test with their own players!

But in order to do this I guess I need some samples from a trustworthy source... ie: your good self ;)


Cheers

[RedDwarf69]

wrong
every mpeg-4 player supporting specific mpeg-4 features supports any mpeg-4 stream using these features no matter what encoder was used

I saw one of these Sony players and I can confirm they don't play XviD, the player was returned without trying anything more. But on a forum I read someone saying that really the videos are played correctly changing the FourCC.
The guy emailed Sony and they said they don't want to support XviD because is used mainly for piracy. :rolleyes:

[multicone]

word!
The only bet I'd make on future standalone support is AVC in MP4. Nero will make that happen if the chips finally become available, and we can jump on the bandwagon with x264 & mp4box.

... and AVC in MKV, for AC3 audio ? http://www.z500series.com/forum/index.php?showtopic=119

[SeeMoreDigital]

And ChristianHJW recently posted a suggestion (on the Zensonic forum) concerning playback of audio+video OGM files: -

http://www.z500series.com/forum/index.php?showtopic=106&st=0&#entry553


Cheers

[vlada]

This looks promissing. I hope we'll see a player with Matroska support soon.
Regarding to Sony players, did anybody try if XviD really works after changing FourCC?