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The Advanced Linux Sound Architecture (ALSA) - utilities
a1992044d5
The channel selection currently does not work properly when there is a driver-provided non-ALSA-traditional channel map but no manual channel map was explicitely requested with "-m". For example, the CEA/HDMI 8ch map is FL,FR,RLC,RRC,FC,LFE,RL,RR. Note that it is otherwise the same as the traditional ALSA channel map, except that the traditional rear speakers are considered rear-center speakers and the traditional side speakers are considered rear speakers. Speaker-test tries to play back channels in this following order: 0, /* Front Left */ 4, /* Center */ 1, /* Front Right */ 7, /* Side Right */ 3, /* Rear Right */ 2, /* Rear Left */ 6, /* Side Left */ 5, /* LFE */ When it is the time to play back Side Left/Right, speaker-test tries to look for SL/SR in the chmap, but doesn't find it, so it just plays back channels 6/7 (which indeed are the side speakers, or RL/RR in this channel map - so the correct channels are selected). When it becomes the time to playback Rear Left/Right, speaker-test again tries to find RL/RR in the chmap, and this time it does find them in the chmap positions 6/7. So the channels 6/7 are tested twice and 2/3 are never tested. To fix this, define a generic playback order channel_order[] to be used when the channel map is present (but not user-defined) and generate a (speaker/playback number => channel number) mapping with the channels ordered in the following order: 1. regular channels found in channel_order[] in the defined order, 2. channels not found in channel_order[] ordered by channel number. 3. UNKNOWN channels ordered by channel number. 4. NA channels ordered by channel number. For channels outside the channel map just use their channel numbers (so they will be last after all of the above). For example, if the playback device has a fictional default channel map of FR,FL,UNKNOWN1,FOO,BAR,RR,RL,UNKNOWN2, the playback order will be FL,FR,RR,RL,FOO,BAR,UNKNOWN1,UNKNOWN2(,any_extra_channels). When the channel mapping is specified manually, the specified order is used for playback as before. Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi> Signed-off-by: Takashi Iwai <tiwai@suse.de> |
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| alsaconf | ||
| alsactl | ||
| alsaloop | ||
| alsamixer | ||
| alsaucm | ||
| amidi | ||
| amixer | ||
| aplay | ||
| iecset | ||
| include | ||
| m4 | ||
| po | ||
| seq | ||
| speaker-test | ||
| utils | ||
| .gitignore | ||
| acinclude.m4 | ||
| ChangeLog | ||
| configure.in | ||
| COPYING | ||
| gitcompile | ||
| INSTALL | ||
| Makefile.am | ||
| README | ||
| TODO | ||
Advanced Linux Sound Architecture - Utilities ============================================= This package contains the command line utilities for the ALSA project. The package can be compiled only with the installed ALSA driver and the ALSA C library. alsaconf - the ALSA driver configurator script alsactl - an utility for soundcard settings management aplay/arecord - an utility for the playback / capture of .wav,.voc,.au files amixer - a command line mixer alsamixer - a ncurses mixer amidi - a utility to send/receive sysex dumps or other MIDI data iecset - a utility to show/set the IEC958 status bits You may give a look for more information about the ALSA project to URL http://www.alsa-project.org. Jaroslav Kysela <perex@perex.cz>