GPAC MP4Box Information, Feature Requests & Discussions [No bug reports]

[SeeMoreDigital]

Originally Posted by HQ-LQ

but not 'avc in mkv'

If you want to see better support for Mpeg4 AVC in MKV then that's up to the Matroska guys to sort out, not MP4Box.


Cheers

[bond]

i doubt there is a chance that mp4box will support mkv output, its a mpeg-4 systems tool

[nexus]

Are avc raw streams correctly handled by mp4box?

I can't mux streams with mp4box which are extracted with avi2raw or with mkvextract.

Btw. which extension should the raw avc stream have? m4v?

[Doom9]

yes.. been using that in MeGUI for a long time and nobody has reported any problem.
.264

[yakima]

probably i've missed something, though i did use search. however, i've been off for some time and now, after updating to mp4box 0.3.0, i've found something odd:

when i use mp4box to convert an avi to mp4, no bifs (or scene) and od are generated, i just have the plain two tracks video and audio. is this supposed to be that way??? and if so, why? or: what could i be doing wrong? (i use -add, -nodrop and that's it).

[SeeMoreDigital]

Hi yakima,

Did your .AVI source contain both video and audio streams?

Using MP4Box 0.3.0.7 - 22 06 2005 14.32.48, together with YAMB 1.3 Alpha1 v1, I've just tried muxing an the following sources: -

An .AVI source containing 1No Mpeg4 video stream and 1No 2Ch MP3 audio stream....
And got an MP4 file with video, BIFF's and OD's but no MP3 audio stream.

An .AVI source containing 1No Mpeg4 video stream and 1No 2Ch AAC-LC audio stream....
And got an MP4 file with video, BIFF's and OD's but no AAC audio stream.

An .AVI source containing 1No Mpeg4 video stream. And an separate .AAC source with 1No 2Ch AAC-LC stream...
And got an MP4 file with video (track 201), audio (track 101), BIFF's (track 1) and OD's (track 2).... So it works for me here

EDIT: I also tried...
An .AVI source containing 1No Mpeg4 video stream. And an separate .MP4 source with 1No 2Ch AAC-LC stream...
And got an MP4 file with video (track 201), audio (track 101), BIFF's (track 1) and OD's (track 2).

An .MP4 source containing 1No Mpeg4 video stream. And an separate .MP4 source with 1No 2Ch AAC-LC stream...
And got an MP4 file with video (track 201), audio (track 101), BIFF's (track 1) and OD's (track 2).



Cheers

[yakima]

hi seemoredigital,
thanks for testing, it's good to know that nothing has changed in that regard.
i had an avi audio/video as input and an a/v mp4 with only 2 tracks as output.
however, i have the 0.3.1 dev - maybe i shouldn't have been so daring. i'll revert to 0.3.0.7 or something and do a clean install, maybe something was messed up ..

[bond]

there is no need for the bifs/od

[Drachir]

For ISO/IEC 14496-12 ISO base media file format there is no need of BIFS/OD.

But for ISO/IEC 14496-14 MP4 file format there should be a BIFS/OD Track.

If am not wrong.

[bond]

Originally Posted by Drachir

But for ISO/IEC 14496-14 MP4 file format there should be a BIFS/OD Track.

no, its not mandatory
isma compliance requires it, but who cares about that?

[SeeMoreDigital]

Originally Posted by bond

no, its not mandatory
isma compliance requires it, but who cares about that?

Agreed...

All the .MP4 encodes I've generated with BIFS and OD data have played perfectly in hardware, after being removed... If that's what you are worrying about.

And if you want to create encodes suitable for streaming.... mux your Mpeg4 video and AAC audio streams into .MOV


Cheers

[bond]

Originally Posted by SeeMoreDigital

And if you want to create encodes suitable for streaming.... mux your Mpeg4 video and AAC audio streams into .MOV

why should mov stream better than mp4?

[Hyper Shinchan]

or is it only easier to spread?

[SeeMoreDigital]

Originally Posted by bond

why should mov stream better than mp4?

If you remember, a while ago I've carried out .MOV and .MP4 "streaming tests" using the same AAC-LC and Mpeg4 SP streams muxed into the different containers.

Each were embedded into their own web page using QuickTime as the player.... The .MOV file streamed almost instantly. While the .MP4 file needed around 50% of the file to be downloaded (buffered I guess) before streaming commenced.

I guess I could run the tests again though.


Cheers

[Drachir]

In ISMA 1.0 the simple BIFS scene and OD are there to be compatible with 14496-1 Mpeg 4 Systems.

ISO/IEC 14496-4 Second Edition(not the latest one) - Conformance testing
3.7 MP4 File Format
3.7.1 Writing
If an atom defined in this specification is written, it must be formatted to this specification. A valid MP4 file with no tracks has at least: moov, mvhd. If it is a presentation or the target of an OD URL, an iods is required, containing an IOD or OD respectively. Only MP4 files used in editing (as the target of a data reference URL) may lack the IOD.
Any track must contain: trak, tkhd, mdia. A mdia must contain mdhd, hdlr, and minf. A minf must contain a suitable media header, a dinf and a stbl. dinf must contain dref; and a stbl must contain stsd, and if there are any samples, an stts, stsz, stco, stsc. The sample table entries must be consistent about the number of samples in a track. Extensions should use the UUID mechanism. Track identifiers must be unique within the file. The containment hierarchy defined in the specification must be followed. Very few atoms (for example, user data and UUID extension) are allowed to occur in multiple containers. Fields marked reserved should be written to the standard value. A presentation must contain at least a BIFS track, referenced by the IOD (as in the systems specification).

Or take a look at this discussion here: https://sourceforge.net/forum/forum....orum_id=287546

Question: Is one Video ES and one Audio ES a Presentation ? - From my point of view I would say - yes

Handbrake create files with File Brand "mp42" - but there is no BIFS/OD Track.
MeGUI create files with File Brand "isom"(ISO/IEC 14496-12) if there is more then one Audio ES.
Recode create files with File Brand "mp42"or"avc1" - but with more then one Audio ES the Scene don't make sense.

I am just interested if this is all right(ISO Conformance).

At what point do I have a Presentation?

[SeeMoreDigital]

Hi Drachir,

May I ask, are you asking these questions out of "interest" or for some other reason you're worried about?


Cheers

[Drachir]

I am interested. And I thing the File Brand should help the player to decide how to deal with the file - with what the player have to anticipate. Will there be a BIFS/OD Track with more information how to display the streams? Or just play the biggest V/A stream.

[yakima]

well, aside from the question if bifs/od are needed or not, it says in the gpac documentation that they are being created upon add (as long as you only have 1 audio and 1 vid, otherwise of course not).

i have (re)installed mp4box 0.3.0.7 now, and it still produces a/v mp4s with no bifs/od:
- if i only add vid from an avi, i get bifs/od
- if i add the full audio/video avi, no bifs/od
- if i add vid from avi and audio from mp4, no bifs/od

could it be that there have been some changes since 0.2.3 or that this is a matter of syntax (there used to be -import and -merge), such that -add acts differently if more than 1 stream is imported?

i am quite clueless on this, but i don't like it if things do things differently than advertised

... tell me this behavior is as defined for some good reason, and i'll bear it ...

[SeeMoreDigital]

Well, what more can I say yakima?

MP4box.exe works exactly as I've said.... If it does not for your (with WinXP) set-up, then something might be wrong at your end


Cheers

[yakima]

well, yes it does. and: it works exactly as i said.

thing is, the files i muxed contained an mp3 audio track, and it seems mp4box no longer sets -isma on default if the audio track is mp3 (it says in the doc: "When using -add option, MP4Box will automatically create default BIFS and OD tracks to make the resulting file compliant with the ISMA 1.0 standard if possible"). if i use -isma -add on my files, bifs/od are created.

does anyone know why they changed this default? is there some problem with mp3 and -isma?