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Open Sound System
OSS 4.x User's Guide
osscore - Open Sound Sytem core audio framework.
Open Sound System core audio support psudo driver. This driver implements the core Open Sound System API for audio, midi, mixer and synth functions. This driver also implements the OS driver interface as well as device configuration and setup. More information on programming on the OSS API is avaialable at: http://manuals.opensound.com/
- ac97_recselect When set to 1 this option enables independent recording source selection for the left and the right channel
on AC97 devices. In this way it's possible to record audio
streams so that (for example) the left channel signal comes
from the microphone and
the right channel signal from line-in. However when this
option is enabled it's only possible to select the recording
source by using a fully OSS 4.0 compatible mixer program such
Default: 0 - recording source is common to both channels.
- ac97_amplifier When set to 1 this option enables the speaker power amplifier feature of AC97 codec (if available).
Some boards have this inverted, so this feature can be
disabled by setting this option to 0.
Affects all AC97 based audio devices in the system.
Default: -1=autodetect correct setting.
- cooked_enable By default OSS will let applications to use sampling rates and formats that are not supported by the hardware.
Instead OSS performs the necessary format conversions in
software. Applications that don't tolerate this kind of
conversions usually disable them by using features of the OSS
API (SNDCTL_DSP_COOKEDMODE). If this option is set to 0 then
the format conversions will be disabled for all applications
and devices unless the application explicitly enables them.
Default: 1 - conversions are enabled.
This option should not be changed without very strong reasons.
- detect_trace Internal debugging (do not change). Default: 0
- dma_buffsize By default OSS will allocate audio DMA buffers with some system dependent default size (usually 64k but sometimes
smaller). It is possible to change this default allocation by
setting this option. Value of 0 means that the default size
will be used. Value between 16 and 128 (kilobytes) can be used
if the default size is not suitable for some reason.
Default: 0 - system dependent buffsize.
This option mustn't be changed unless it's absolutely necessary.
- max_intrate Set the maximum number of interrupts per second. Default: 100 interrupts per second which equals to about
10 msec minimum latencies.
- vmix_disabled The virtual mixer subsystem can be disabled by setting this configuration option to 1.
Default: 0 - virtual mixer is enabled.
- vmix_loopdevs Optionally the virtual mixer subsystem can create special loopback audio devices that can be used to record the
output mix sent to the device. This option tells how many
loopback devices will be created (0, 1 or 2). If there are
multiple audio devices in the system the all of them will have
the same number of loopback devices.
Default: 0 - no loopback devices are created.
This setting should be left to 0 unless there are specific
reasons to enable the loopback devices.
- vmix_no_autoattach By default (0) the low level drivers for most sound cards will automatically
attach virtual mixer (vmix) to the primary audio devices of the cards.
In some situations it may be necessary to attach virtual mixer using
nonstandard parameters. If vmix_no_autoattach is set to 1 then user
can use vmixctl attach command to attach virtual mixer manually to
Default: 0 - Automatically attach virtual mixer.
osscore.conf Device configuration file
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