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Gawen
18th April 2002, 09:25
Does anybody here know wich Microsoft codec is referred to in the MP4-Video FAQ? Is it MP4V3?

From the Faq:
11. Does an implementation of the video codec exits? Is it available? How can we get it : any registration, payment, problems of copyrights and patents?

There exist two official MPEG implementations of the Video codec : one in C provided by the European project ACTS-MOMUSYS, and one in C++ provided by Microsoft.

( http://mpeg.telecomitalialab.com/faq/mp4-vid/mp4-vid.htm )

Doom9
18th April 2002, 12:10
I think they refer to the codec I have available on the source page

Gawen
18th April 2002, 18:21
Thanks a lot!

Neo Neko
18th April 2002, 20:43
MS MPEG4 can't be used in MP4 is I am not mistaken. MS MPEG4 is not compliant is it not? Just a question......

Gawen
19th April 2002, 02:50
I will know after muxing with mp4creator :-)
(And post the comparision results to divxenc afterwards)

DeXT
19th April 2002, 14:36
No MSMPEG4/DivX 3 is not ISO compliant, it can hardly be called MPEG-4. It's just a partial, incompatible implementation. DivX 4 and upwards is ISO compliant, as well as XviD.

Nic
19th April 2002, 17:34
Apparently that is not quite the case...

DivX3/MSMPEG-4v3, according to what I read recently, is pretty MPEG-4 compatible & it is possible to convert a Div3 stream to an MP4 one...(without re-encoding obviously)

Apparently it just has header/flag/bitstream information removed to lower the overheads...

But this is just what ive heard (actually I think it was from -h....? maybe he will comment :) )

-Nic

Neo Neko
20th April 2002, 05:24
Indeed.

Chibi Jasmin
20th April 2002, 11:50
Originally posted by Nic
Apparently that is not quite the case...

DivX3/MSMPEG-4v3, according to what I read recently, is pretty MPEG-4 compatible & it is possible to convert a Div3 stream to an MP4 one...(without re-encoding obviously)

Apparently it just has header/flag/bitstream information removed to lower the overheads...

But this is just what ive heard (actually I think it was from -h....? maybe he will comment :) )

-Nic

I'd very much like to hear more about this.

In other words: Where is the tool that can convert Div3 into MP4? Where is the fully working and compliant MP4-Player? :-)

Nic
20th April 2002, 12:29
Unfortunatly, there is no such converter...AFAIK...Im not even sure if this info is correct, but it's what I heard.

I'd be surprised if the MPEG4IP player isn't the most ISO compliant one....But its hard to say.

-Nic

Chibi Jasmin
20th April 2002, 13:01
Yeah, everyone says xvid and divx5 are compliant and the mpeg4ip player is, too. But I still have more failures than successes playing content encoded with xvid/divx5 with the mpeg4ip player.

Well, we'll be patient and wait for things to come... :-)

I just thought the div3->MP4 thing will make a lot of people happy. If it really works, there will be a converter tool for sure...

DSPguru
20th April 2002, 13:19
Originally posted by Chibi Jasmin
I just thought the div3->MP4 thing will make a lot of people happy. If it really works, there will be a converter tool for sure... if it's only a matter of adding headers and using different luts for flags, i guess we could also have a realtime playbacking convertor. (dsf ?)

Nic
20th April 2002, 13:43
I dont think ill comment on it anymore as I really dont have any knowledge on it to back it up :( ... Its just what I heard.

:)

-Nic

Neo Neko
21st April 2002, 00:11
My full understanding is this. Microsoft's latest encoder they are working on will be able to put out ISO-MPEG4. But it will only be offered to the professional private sector. Because the home user is a pawn of the empire and needs no choice or interoperability. I have always seen, thought, and been told that MS-MPEG4 is very deviant from the specs. So much so that changing headders whould acomplish nothing. If something like this were possible don't you think that DXN or someone else would have made a utility like that. I remember the whining that was heard over at divx.com when news of the sigmadesigns X-card were released. Everyone was super happy till they found out much to their dismay that Divx3 decoding support was not included. Sigma Designs and most other companies will not ever license that bit of code due to it super shady past. Sure some people use it for legitimate backup of their personal DVDs and do not share. We are the minority. The majority of people pirating still use Divx3 for what ever reasons. So by shunning this bit of code it saves them on licensing, and the hell of hot coals that would be dumped on them for seeming to support Divx3. If it were possible to just change the headders don't you think that DXN would have done it?

I am not trying to offend anybody, and I damn well could be wrong. Anyone else have some intelligent discourse or alternate opinions please post.

philippas
21st April 2002, 15:03
Don't you think though that it's a bit strange that DXN can very easily decode divx3 content without having the source ? Also another clue is the name that MS gave to the codec mpeg-4 ver 3 ?

Gawen
21st April 2002, 16:14
Seems i have an answer to the M$ codec question:

M$-MPEG4-V3 is not ISO MPEG-4, but there is a M$ ISO MPEG-4 codec supported by the format SDK and offically available in mplayer 7 Mac and Pocket-PC 2002 player.
Availability in win32 would have to be tested.

http://groups.google.de/groups?q=iso+mpeg-4++group:microsoft.public.windowsmedia.sdk&hl=de&selm=kSBKTHXbBHA.186%40cppssbbsa01.microsoft.com&rnum=4
http://search.support.microsoft.com/search/default.aspx?Catalog=LCID%3D1033%26CDID%3DEN-US-KB%26PRODLISTSRC%3DON&Product=msall&Query=iso%2520mpeg-4&Queryc=iso+mpeg-4&withinResults=false&srchstep=0&KeywordType=PHRASE&Titles=false&numDays=&maxResults=25

philippas
21st April 2002, 17:29
Yes also if you download WMEnc 7.1 you'll see that you can select wm7,wm8 and iso mpg-4 video codecs when you set an encode. But the question is how much different the divx3 codec is from the iso mpeg-4 and if it's possible without transcoding to convert divx3 to mp4.
I think only DXN can answer that.

Gawen
21st April 2002, 18:49
Since my last post i tried exactly this. Did a CIF clip with picvideo, converted to wmv/(would like to be)ISO MPEG-4 V1, opened it in Graphedit and wondered. It was opened by default from divx_c32.ax. Used bindump.ax to dump to raw data to capture.divx. Dumped Header from bindump said FourCC MP4S. Deinstalled divx_c32.ax. Opened again, was opened with M$ MPEG-4 Decoder. Muxed capture.divx with mp4creator, tried to play, crash on open. QT/Envivio did not crash, but also showed not picture, at least the time line moved.

What does it mean? Imho div3/mp43 is not mp4s and mp4s is not reusable ISO MPEG-4 for transcoding to mpeg4ip. I think DXN knew early about mp4s from their div3 works and maybe took that knowledge to create opendivx. divxdec.ax today does not do more than the divx_c32.ax could before.

M$MP4 evolution was mp41 - mp42 - mp43 - - mp4s and leaved then with msvid7 + 8.

Nic
21st April 2002, 21:02
Seeing I started this speculation, which is all this is....This is where I heard it most recently:

http://www.xvid.org/forum/viewtopic.php?topic=445&forum=4&2
(read -h's reply)

I dont know anymore than that :)

Cheers,
-Nic