The VideoLAN Forums

Hi everybody,
I have emerged vlc-0.8.1 on Gentoo Linux using the instructions found at http://www.videolan.org/vlc/download-gentoo.html, that is using the use flags
"dvd nls xv bidi truetype wxwindows imlib matroska faad png", but it seems that some module is missing: in fact when I try to listen to aacplus streams as the ones at http://somafm.com I get the following error:

[00000227] main packetizer debug: looking for packetizer module
[00000227] main packetizer debug: probing 10 candidates
[00000226] m4a demuxer error: cannot find mp4a packetizer
[00000226] main demuxer warning: no demux2 module matching "m4a" could be loaded[00000220] main input error: no suitable demux module for `http/m4a://64.202.98.51:8110'

On another pc with Debian Linux and the same version of vlc I have no problems with this kind of streams. Can anybody help me to understand which modules are missing, so that I can try to implement it with appropriate use flags on Gentoo?

Well it seems a mp4/m4a plugin is missing, but personally i have no clue why. This module should always be compiled by VLC. it's one of it's default modules.

I'm having the exact same problem on my Gentoo-box:

anders@linuxbox:~$vlc http://www.tuner2.com/cgi-bin/listen.pls?sid=24
VLC media player 0.8.1 Janus
[00000221] access_http access: ICY server found, m4a demuxer selected
[00000223] m4a demuxer error: cannot find mp4a packetizer
[00000219] main input error: no suitable demux module for `http/m4a://sc3.audiorealm.com:9772'

Despite the fact that I apparently have the plugins:

anders@linuxbox:~$ls /usr/lib/vlc/demux/
liba52sys_plugin.so libau_plugin.so libflac_plugin.so libm3u_plugin.so libmp4_plugin.so libogg_plugin.so librawdv_plugin.so libts_plugin.so
libaac_plugin.so libavi_plugin.so libh264_plugin.so libm4a_plugin.so libmpga_plugin.so libplaylist_plugin.so libreal_plugin.so libvobsub_plugin.so
libaiff_plugin.so libdemuxdump_plugin.so libid3_plugin.so libm4v_plugin.so libmpgv_plugin.so libps_plugin.so libsgimb_plugin.so libwav_plugin.so
libasf_plugin.so libdtssys_plugin.so libid3tag_plugin.so libmjpeg_plugin.so libnsv_plugin.so libpva_plugin.so libsubtitle_plugin.so

v. 0.7.2 mysteriously stopped working for me today, packetizer/demux errors
so i updated to v. 0.8.1, same errors
hmm...
emerged very latest (~x86) ffmpeg & faad2
re-emerged vlc
magic !
it streams aacplus again

ffmpeg-0.4.9_pre1 USEing aac encode sdl
faad2-2.0-r4
vlc-0.8.1 USEing a52 alsa dts faad ffmpeg gnutls live mad mpeg2 nls

on of the few problems of gentoo
it has these kinds of problems quite often actually.

v. 0.7.2 mysteriously stopped working for me today, packetizer/demux errors
so i updated to v. 0.8.1, same errors
hmm...
emerged very latest (~x86) ffmpeg & faad2
re-emerged vlc
magic !
it streams aacplus again

ffmpeg-0.4.9_pre1 USEing aac encode sdl
faad2-2.0-r4
vlc-0.8.1 USEing a52 alsa dts faad ffmpeg gnutls live mad mpeg2 nls

I did the same here, with no success (and I also have ~x86 in my make.conf):
# emerge sync
# USE="aac encode sdl" emerge ffmpeg faad2
# USE="a52 bidi dvd faad ffmpeg matrioska ogg vorbis wxwindows alsa dts gnutls live mad mpeg2" emerge vlc
$ vlc tagstranceaacPlus48.pls
VLC media player 0.8.1 Janus
[00000232] access_http access: ICY server found, m4a demuxer selected
[00000236] m4a demuxer error: cannot find mp4a packetizer
[00000230] main input error: no suitable demux module for `http/m4a://205.188.234.35:8012'

Well it seems a mp4/m4a plugin is missing, but personally i have no clue why. This module should always be compiled by VLC. it's one of it's default modules.

My guess is that using the demuxer for M4A files is wrong, because the aacPlus streams don't have anything to do with the MP4 file format, they are in ADTS AAC format. So libaac_plugin.so probably would be the right one, but I have no idea why this problem obviously only shows up on Gentoo then.

Well actually that's not 100% true. Because in VLC there is a chain, and that means that something always has to pass trough a demuxer. Even if that does nothing at all

but still what is the exact problem here, is a mystery to me.

add stream to your USE flags for vlc. This allowed aacplus streams to work.

USE flags are both a strength and a huge weakness of gentoo.