audio codec mp3 is not supported by mp4frag?

[hexingb]

I have a mp4 file in which mp3 audio codec data contained ( I get it using ffmpeg -i http://ip/live.flv -vcodec libx264 -acodec libmp3lame -f mp4 a.mp4). I do mp4frag --src a.mp4 but two MP4_CHECK failed.
MP4_CHECK(descr_length >= 15); in mp4.cc line 513
MP4_CHECK(*esds_ptr == 5); in mp4.cc line 515

I comment out these two lines and fragments generated. I create a crossdomain.xml and put it and fragments under a http server: python -m SimpleHTTPServer。I play the manifest.f4m using osmf player。video is OK but no audio.

I found no mp3 audio codec mp4 files so I only tested with ffmpeg-generated-mp4 files. Is it can be solved?

[eugene-k]

MP3 codec is not supported. It can be solved but right now I have no time for it, sorry.

[hexingb]

Could you give me a hint doing this?
I tried add every mp3 tag into SampleEntry(_offset, _size, _timestamp, etc), but I don't know what should be assigned to Media.audioextra as mp3 has no sequence header(am I right?)
Are there any other issues should be concerned on doing mp3 support?
And another question: In adobe specification(http://download.macromedia.com/f4v/video_file_format_spec_v10_1.pdf Annex C.2) moov box is mandatory required. Or in http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/devnet/hds/pdfs/adobe-hds-specification.pdf, afra, abst, moof boxes are required. but mp4frag-generated fragments begin with on mdat box. Why?

Thanks in advance for your direction. I really need this mp3 codec support ( and vp6 video codec further) and hope to contribute my help to this project.