opusenc(1) | opus-tools | opusenc(1) |
NAME¶
opusenc - encode audio into the Opus formatSYNOPSIS¶
opusenc [ -v ] [ -h ] [ --speech ] [ --music ] [ --bitrate kbit/sec ] [ --vbr ] [ --cvbr ] [ --hard-cbr ] [ --comp complexity ] [ --framesize 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.opusDESCRIPTION¶
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.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)
- --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
- --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/vorbis/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
opusenc --bitrate 160 input.wav
output.opus
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 format with low latency settings, but not really for actual low latency usage.AUTHORS¶
Gregory Maxwell <greg@xiph.org>SEE ALSO¶
opusdec(1), opusinfo(1), oggfwd(1)2012-05-28 | Xiph.Org Foundation |