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       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:


       o 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 as  ossxmix.
              Default: 0 - recording source is common to both channels.

       o 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.

       o 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.

       o detect_trace
              Internal debugging (do not change). Default: 0

       o 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.

       o max_intrate
              Set  the  maximum number of interrupts per second.  Default: 100
              interrupts per second which equals  to  about  10  msec  minimum

       o vmix_disabled
              The  virtual  mixer  subsystem  can  be disabled by setting this
              configuration option to  1.   Default:  0  -  virtual  mixer  is

       o 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.

       o 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 the device(s).
              Default: 0 - Automatically attach virtual mixer.

       o excl_policy
              The O_EXCL open() flag can be used by  programs  to  bypass  the
              virtual  mixer.  Setting  excl_policy to 1 or 2 makes OSS ignore
              O_EXCL.  A setting  of  1  ignores  O_EXCL  from  all  but  root
              processes, while a setting of 2 always ignores O_EXCL.  Default:
              0 - Do not ignore O_EXCL.

       o mixer_muted
              By default OSS will set most volume controls to  audible  level.
              If this causes problems then it's possible to ask OSS to set the
              levels to zero when the drivers are loaded. However  the  levels
              saved  with  the  savemixer  utility will get loaded few moments
              later when all OSS drivers have been  started.  Note  that  just
              some of the OSS drivers honor this setting.  Values: 0 (default)
              - Use audible volumes, 1 - Set volumes to low.


       /usr/lib/oss/conf/osscore.conf Device configuration file


       4Front Technologies

                                 31 July 2010                       osscore(7)