[gst-devel] faac encoded m4a files identified as video/quicktime

[Gunnar Degnbol]

Playing faac encoded m4a files are not possible in Rhythmbox because 
gstreamer returns the type video/quicktime instead of audio/x-m4a, and 
Rhythmbox is not a video player. Files encoded with iTunes play in 
Rhythmbox, and the faac files play in iTunes and on my iPod.

The only reference to this problem I have found is this post from last 
august:
http://readlist.com/lists/gentoo.org/gentoo-user/0/2833.html


"gst-launch -v filesrc=filename ! spider ! alsasink" shows this for an 
iTunes file:

...
/pipeline0/spider0/qtdemux0.sink: caps = audio/x-m4a
/pipeline0/spider0/qtdemux0.sink: active = TRUE
/pipeline0/spider0/qtdemux0.audio_00: active = TRUE
/pipeline0/spider0/qtdemux0.audio_00: caps = audio/mpeg, 
mpegversion=(int)4, rate=(int)44100, channels=(int)2
/pipeline0/spider0/faad0.sink: caps = audio/mpeg, mpegversion=(int)4, 
rate=(int)44100, channels=(int)2
/pipeline0/spider0/faad0.sink: active = TRUE
...

And this for an faac file:

...
/pipeline0/spider0/qtdemux0.sink: caps = video/quicktime
/pipeline0/spider0/qtdemux0.sink: active = TRUE
/pipeline0/spider0/qtdemux0.audio_00: active = TRUE
/pipeline0/spider0/qtdemux0.audio_00: caps = audio/mpeg, 
mpegversion=(int)4, rate=(int)44100, channels=(int)2
/pipeline0/spider0/faad0.sink: caps = audio/mpeg, mpegversion=(int)4, 
rate=(int)44100, channels=(int)2
/pipeline0/spider0/faad0.sink: active = TRUE
...

A real quicktime movie shows this:

...
/pipeline0/spider0/qtdemux0.sink: caps = video/quicktime
/pipeline0/spider0/qtdemux0.sink: active = TRUE
/pipeline0/spider0/qtdemux0.video_00: active = TRUE
/pipeline0/spider0/qtdemux0.audio_00: active = TRUE
/pipeline0/spider0/qtdemux0.audio_00: caps = audio/mpeg, layer=(int)3, 
mpegversion=(int)1, rate=(int)32000, channels=(int)2
/pipeline0/spider0/mad0.sink: caps = audio/mpeg, layer=(int)3, 
mpegversion=(int)1, rate=(int)32000, channels=(int)2
/pipeline0/spider0/mad0.sink: active = TRUE
...

I don't know the difference in the file between an iTunes encoded m4a 
and an faac file, but iTunes and iPod happily accepts the faac files.
Since the faac file does not contain any video data, the video/quicktime 
file type is wrong.


Gunnar