[FFmpeg-devel] [PATCH] get the right value for the dac3 atom

Baptiste Coudurier baptiste.coudurier
Fri Sep 5 01:51:11 CEST 2008

vmrsss wrote:
> Hi
> On 4 Sep 2008, at 19:43, Baptiste Coudurier wrote:
>>> The are different ways of muxing ac-3 in mov, all valid. The dac3  
>>> atom
>>> inside mov has been used only by apple in QuickTime 7.5 when they
>>> introduced an ac3 importer.
>> It's standardized by ETSI now, so there is only one way to mux ac-3 in
>> mp4. .mov is another story of course, but the official way will always
>> be apple's one. I could not generate .mov containing ac-3 yet, samples
>> welcome.
> Well, my experience is that with current ffmpeg, x264 + ac3 works well  
> in QT 7.5 if the extension is .mov and does not ("An invalid sample  
> description was found in the movie") if the extension is mp4 (all the  
> rest being equal). (for information, mplayer can't find the audio  
> stream in any of the files, while ffplay plays them just fine.)  
> Perhaps I can help with testing.

Nice to hear, I confirmed this too.
Quicktime player recognizes the ac-3 track (Displaying "AC3" in
informations) when placed in .mov and .m4v, however it chokes on .mp4
too, QT is known to be picky about .mp4.

Thanks for testing.

Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
Smartjog USA Inc.                                http://www.smartjog.com
Key fingerprint                 8D77134D20CC9220201FC5DB0AC9325C5C1ABAAA

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