diff options
| -rw-r--r-- | qapi/audio.json | 6 | ||||
| -rw-r--r-- | qemu-options.hx | 15 |
2 files changed, 21 insertions, 0 deletions
diff --git a/qapi/audio.json b/qapi/audio.json index e45218f..83312b2 100644 --- a/qapi/audio.json +++ b/qapi/audio.json @@ -11,6 +11,11 @@ # General audio backend options that are used for both playback and # recording. # +# @mixing-engine: use QEMU's mixing engine to mix all streams inside QEMU and +# convert audio formats when not supported by the backend. When +# set to off, fixed-settings must be also off (default on, +# since 4.2) +# # @fixed-settings: use fixed settings for host input/output. When off, # frequency, channels and format must not be # specified (default true) @@ -31,6 +36,7 @@ ## { 'struct': 'AudiodevPerDirectionOptions', 'data': { + '*mixing-engine': 'bool', '*fixed-settings': 'bool', '*frequency': 'uint32', '*channels': 'uint32', diff --git a/qemu-options.hx b/qemu-options.hx index 793d70f..996b6fb 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -433,6 +433,7 @@ DEF("audiodev", HAS_ARG, QEMU_OPTION_audiodev, " specifies the audio backend to use\n" " id= identifier of the backend\n" " timer-period= timer period in microseconds\n" + " in|out.mixing-engine= use mixing engine to mix streams inside QEMU\n" " in|out.fixed-settings= use fixed settings for host audio\n" " in|out.frequency= frequency to use with fixed settings\n" " in|out.channels= number of channels to use with fixed settings\n" @@ -493,6 +494,10 @@ output's property with @code{out.@var{prop}}. For example: -audiodev alsa,id=example,out.channels=1 # leaves in.channels unspecified @end example +NOTE: parameter validation is known to be incomplete, in many cases +specifying an invalid option causes QEMU to print an error message and +continue emulation without sound. + Valid global options are: @table @option @@ -503,6 +508,16 @@ Identifies the audio backend. Sets the timer @var{period} used by the audio subsystem in microseconds. Default is 10000 (10 ms). +@item in|out.mixing-engine=on|off +Use QEMU's mixing engine to mix all streams inside QEMU and convert +audio formats when not supported by the backend. When off, +@var{fixed-settings} must be off too. Note that disabling this option +means that the selected backend must support multiple streams and the +audio formats used by the virtual cards, otherwise you'll get no sound. +It's not recommended to disable this option unless you want to use 5.1 +or 7.1 audio, as mixing engine only supports mono and stereo audio. +Default is on. + @item in|out.fixed-settings=on|off Use fixed settings for host audio. When off, it will change based on how the guest opens the sound card. In this case you must not specify |