opusenc(1)							    opus-tools								opusenc(1)

NAME

       opusenc - encode audio into the Opus format

SYNOPSIS

       opusenc	[ -v ] [ -h ] [ --speech ] [ --music ] [ --bitrate kbit/sec ] [ --vbr ] [ --cvbr ] [ --hard-cbr ] [ --comp complexity ] [ --frame-
       size 2.5, 5, 10, 20, 40, 60 ] [ --expect-loss pct ] [ --downmix-mono ] [ --downmix-stereo ] [ --max-delay ms ]  [  --save-range	file  ]  [
       --set-ctl-int  ctl=value  ]  [  --uncoupled  ]  [  --comment tag=value ] [ --artist author ] [ --title track title ] [ --raw ] [ --raw-bits
       bits/sample ] [ --raw-rate Hz ] [ --raw-chan N ] [ --raw-endianness flag ] [ --ignorelength ] input.wav output.opus

DESCRIPTION

       opusenc reads audio data in either raw, Wave, or AIFF format and encodes it into an Opus stream. If the input file is  "-"  audio  data	is
       read from stdin.  Likewise, if the output file is "-" opus data is written to stdout.

       Unless quieted opusenc displays fancy statistics about the encoding progress.

OPTIONS

       -h, --help
	      Show command help

       -v, --version
	      Show the version number

       --speech
	      Optimize for speech

       --music
	      Optimize for music

       --bitrate N.nnn
	      Encoding bitrate in kbit/sec (6-256 per channel)

       --vbr  Use variable bitrate encoding (default)

       --cvbr Use constrained variable bitrate encoding

       --hard-cbr
	      Use hard constant bitrate encoding

       --comp N
	      Encoding computational complexity (0-10, default: 10)

       --framesize N
	      Maximum frame size in milliseconds (2.5, 5, 10, 20, 40, 60, default: 20)
	      Smaller framesizes achieve lower latency but less quality at a given bitrate.
	      Sizes greater than 20ms are only interesting at fairly low bitrates.

       --expect-loss N
	      Percentage packet loss to expect (default: 0)

       --downmix-mono
	      Downmix to mono

       --downmix-stereo
	      Downmix to stereo (if >2 channels input)

       --max-delay N
	      Maximum container delay in milliseconds (0-1000, default: 1000)

       --save-range file
	      Saves check values for every frame to a file

       --set-ctl-int x=y
	      Pass the encoder control x with value y (advanced) Preface with s: to direct the ctl to multistream s
	      This may be used multiple times

       --uncoupled
	      Use one mono stream per channel

       --comment tag=value
	      Add  an  extra  comment.	This may be used multiple times, and all instances will be added to each of the input files specified. The
	      argument should be in the form "tag=value".  See the vorbis-comment specification for well known tag names: http://www.xiph.org/vor-
	      bis/doc/v-comment.html

       --artist artist
	      Set the artist comment field in the comments to artist

       --title title
	      Set the track title comment field to title

       --raw  Raw (headerless) PCM input

       --raw-bits N
	      Set bits/sample for raw input (default: 16)

       --raw-rate N
	      Set sampling rate for raw input (default: 48000)

       --raw-chan N
	      Set number of channels for raw input (default: 2)

       --raw-endianness [0/1]
	      Set the endianness for raw input: 1 for bigendian, 0 for little (defaults to 0)

       --ignorelength
	      Always  ignore  the  datalength  in  Wave headers. Opusenc automatically ignores the length when its implausible (very small or very
	      large) but some STDIN usage may still need this option to avoid truncation.

EXAMPLES

       Simplest usage. Take input as input.wav and produce output as output.opus:
	      opusenc input.wav output.opus

       Produce a very high quality encode with a target rate of 160kbps:
	      opusenc --bitrate 160 input.wav output.opus

       Record and send a live stream to an Icecast HTTP streaming server using oggfwd:
	      arecord -c 2 -r 48000 -twav - | opusenc --bitrate 96 -  - | oggfwd icecast.somewhere.org 8000 password /stream.opus

NOTES

       While it is possible to use opusenc for low latency streaming (e.g. with --max-delay set to 0 and  netcat  instead  of  Icecast)  it's  not
       really  designed  for  this, and the Ogg container and TCP transport aren't the best tools for that application. Shell pipelines themselves
       will often have high buffering. The ability to set framesizes as low as 2.5 ms in opusenc mostly exists to try out the quality of the  for-
       mat with low latency settings, but not really for actual low latency usage.
       Interactive usage should use UDP/RTP directly.

AUTHORS

       Gregory Maxwell <greg@xiph.org>

SEE ALSO

       opusdec(1), opusinfo(1), oggfwd(1)

Xiph.Org Foundation						    2012-05-28								opusenc(1)