Results for ALSA / OpenAL sample rate compatibility

Intel-HDA_OpenAL-ALSA_sampling-rate_tables.txt (text/plain), 3.17 KB, created by Michael Schnake on 2007-09-21 20:33:32 UTC

OpenAL / ALSA sampling rate compatibility for Intel HDA soundcards
==================================================================

media-libs/openal-0.0.8-r2 with 005_all_alsa_default_freq.patch
+---+------------+----------------+--------------+--------------+-----------+-----------+------+
| # | ALSA: rate | OpenAL: device | OpenAL: rate | eff. device  | 44.1kHz   | 48kHz     | DMIX |
+---+------------+----------------+--------------+--------------+-----------+-----------+------+
| 1 |  48000 Hz  |  unspecified   | unspecified  | OSS (dsp)    | distorted | perfect   | No   |
| 2 |  48000 Hz  | alsa / default | unspecified  | ALSA default | no sound  | perfect   | Yes  |
| 3 |  48000 Hz  | alsa / default |   44100 Hz   | ALSA default | stutters  | no sound  | Yes  |
| 4 |  48000 Hz  | alsa / default |   48000 Hz   | ALSA default | no sound  | perfect   | Yes  |
| 5 |  44100 Hz  |  unspecified   | unspecified  | OSS (dsp)    | distorted | perfect   | No   |
| 6 |  44100 Hz  | alsa / default | unspecified  | ALSA default | no sound  | stutters  | Yes  |
| 7 |  44100 Hz  | alsa / default |   44100 Hz   | ALSA default | perfect   | no sound  | Yes  |
| 8 |  44100 Hz  | alsa / default |   48000 Hz   | ALSA default | no sound  | stutters  | Yes  |
+---+------------+----------------+--------------+--------------+-----------+-----------+------+

media-libs/openal-0.0.8-r2 without 005_all_alsa_default_freq.patch (RECOMMENDED)
+---+------------+----------------+--------------+--------------+-----------+-----------+------+
| # | ALSA: rate | OpenAL: device | OpenAL: rate | eff. device  | 44.1kHz   | 48kHz     | DMIX |
+---+------------+----------------+--------------+--------------+-----------+-----------+------+
| 1 |  48000 Hz  |  unspecified   | unspecified  | OSS (dsp)    | perfect   | distorted | No   |
| 2 |  48000 Hz  | alsa / default | unspecified  | ALSA default | stutters  | no sound  | Yes  |
| 3 |  48000 Hz  | alsa / default |   44100 Hz   | ALSA default | stutters  | no sound  | Yes  |
| 4 |  48000 Hz  | alsa / default |   48000 Hz   | ALSA default | no sound  | perfect   | Yes  |
| 5 |  44100 Hz  |  unspecified   | unspecified  | OSS (dsp)    | perfect   | distorted | No   |
| 6 |  44100 Hz  | alsa / default | unspecified  | ALSA default | perfect   | no sound  | Yes  |
| 7 |  44100 Hz  | alsa / default |   44100 Hz   | ALSA default | perfect   | no sound  | Yes  |
| 8 |  44100 Hz  | alsa / default |   48000 Hz   | ALSA default | no sound  | stutters  | Yes  |
+---+------------+----------------+--------------+--------------+-----------+-----------+------+

Legend:

- "ALSA:" means "ALSA configuration file":
	- /etc/asound.conf (system wide), or
	- ~/.asoundrc (user specific)

- "OpenAL:" means "OpenAL configuration file":
	- /etc/openal (system wide), or
	- ~/.openalrc (user specific)

- Columns 2-4 describe what is specified via the respective configuration file.

- "eff. device" is the device being used by OpenAL - either the ALSA default device, or ALSA's OSS emulation (/dev/sound/dsp).

- the next two columns show the result of playing a 44.1kHz / 48kHz file via "mplayer -ao openal"

- the last column states whether another file could be played concurrently (= DMIX functionality)