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opusenc(1)			   opus-tools			      opusenc(1)

NAME
     opusenc - encode audio into the Opus format

SYNOPSIS
     opusenc [ -h ] [ -V ] [ --help-picture ] [ --quiet ] [ --bitrate kbit/s ] [
     --vbr  ]  [  --cvbr ] [ --hard-cbr ] [ --music ] [ --speech ] [ --comp com-
     plexity ] [ --framesize 2.5, 5, 10, 20, 40, 60 ] [ --expect-loss  pct  ]  [
     --downmix-mono ] [ --downmix-stereo ] [ --no-phase-inv ] [ --max-delay ms ]
     [	--title  'track title' ] [ --artist author ] [ --album 'album title' ] [
     --tracknumber 'track number' ] [ --genre genre ] [ --date	YYYY-MM-DD  ]  [
     --comment	tag=value ] [ --picture filename|specification ] [ --padding n ]
     [ --discard-comments ] [  --discard-pictures  ]  [  --raw	]  [  --raw-bits
     bits/sample  ] [ --raw-rate Hz ] [ --raw-chan N ] [ --raw-endianness flag ]
     [ --ignorelength ] [ --serial serial number  ]  [	--save-range  file  ]  [
     --set-ctl-int ctl=value ] input.wav output.opus

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

     Unless  quieted  opusenc  displays  fancy	statistics  about  the	encoding
     progress.

OPTIONS
   General options
     -h, --help
	    Show command help

     -V, --version
	    Show the version number

     --help-picture
	    Show help on attaching album art

     --quietEnable quiet mode. No messages are displayed.

   Encoding options
     --bitrate N.nnn
	    Set target bitrate in kbit/s (6-256 per channel)

	    In VBR mode this specifies the average rate for a large and  diverse
	    collection of audio. In CVBR and Hard-CBR mode it specifies the spe-
	    cific output bitrate.

	    The default for input with a sample rate of 44.1 kHz or higher is 64
	    kbit/s per mono stream and 96 kbit/s per coupled pair.

     --vbr  Use variable bitrate encoding (default)

	    In	VBR  mode the bitrate may go up and down freely depending on the
	    content to achieve more consistent quality.

     --cvbr Use constrained variable bitrate encoding.

	    Outputs to a specific bitrate. This mode  is  analogous  to  CBR  in
	    AAC/MP3  encoders  and  managed mode in Vorbis coders. This delivers
	    less consistent quality than VBR mode but consistent bitrate.

     --hard-cbr
	    Use hard constant bitrate encoding.

	    With hard-cbr every frame will be exactly the same size, similar  to
	    how  speech  codecs work. This delivers lower overall quality but is
	    useful where bitrate changes might leak data in  encrypted	channels
	    or on synchronous transports.

     --musicOverride  automatic  detection and tune low bitrate encoding for mu-
	    sic.  By default, music is detected automatically and the  classifi-
	    cation may vary over time.

	    Tuning  impacts lower bitrates that involve tradeoffs between speech
	    clarity and musical accuracy, and has no impact  at  bitrates  typi-
	    cally used for high quality music encoding.

     --speech
	    Override  automatic  detection  and  tune  low  bitrate encoding for
	    speech.  By default, speech is detected automatically and the  clas-
	    sification may vary over time.

	    Tuning  impacts lower bitrates that involve tradeoffs between speech
	    clarity and musical accuracy, and has no impact  at  bitrates  typi-
	    cally used for high quality music encoding.

     --comp N
	    Set  encoding  computational  complexity  (0-10,  default: 10). Zero
	    gives the fastest encodes but lower  quality,  while  10  gives  the
	    highest quality but slower encoding.

     --framesize N
	    Set  maximum frame size in milliseconds (2.5, 5, 10, 20, 40, 60, de-
	    fault: 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
	    Set expected packet loss in percent (default: 0)

     --downmix-mono
	    Downmix to mono

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

     --no-phase-inv
	    Disable use of phase inversion for	intensity  stereo.  This  trades
	    some stereo quality for a higher quality mono downmix, and is useful
	    when  encoding  stereo  audio that is likely to be downmixed to mono
	    after decoding.

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

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

     --artist artist
	    Set the artist comment field to artist.  This may be  used	multiple
	    times  to  list  contributing  artists individually.  Note that some
	    playback software does not display multiple artists gracefully.

     --album album
	    Set the album or collection title field to album

     --tracknumber N
	    Set the track number comment field to N

     --date YYYY-MM-DD
	    Set the date comment field to YYYY-MM-DD.  This may be shortened  to
	    YYYY-MM or YYYY.

     --genre genre
	    Set  the genre comment field to genre.  This option may be specified
	    multiple times to tag a track with multiple overlapping genres.

     --comment tag=value
	    Add an extra comment.  This may be used multiple times.   The  argu-
	    ment  should  be  in  the  form "tag=value".  See the vorbis-comment
	    specification for well known  tag  names:  https://www.xiph.org/vor-
	    bis/doc/v-comment.html

     --picture filename|specification
	    Attach album art for the track.

	    Either  a  filename for the artwork or a more complete specification
	    form can be used.  The picture is added to a  METADATA_BLOCK_PICTURE
	    comment field similar to what is used in FLAC.  The specification is
	    a  string  whose  parts  are separated by | (pipe) characters.  Some
	    parts may be left empty to invoke default values.  Passing	a  plain
	    filename is just shorthand for the "||||filename" specification.

	    The   format   of	specification  is  [type]|[media-type]|[descrip-
	    tion]|[widthxheightxdepth[/colors]]|filename

	    type is an optional number describing the  nature  of  the	picture.
	    Defined values are from one of:

	      0: Other
	      1: 32x32 pixel 'file icon' (PNG only)
	      2: Other file icon
	      3: Cover (front)
	      4: Cover (back)
	      5: Leaflet page
	      6: Media (e.g., label side of a CD)
	      7: Lead artist/lead performer/soloist
	      8: Artist/performer
	      9: Conductor
	     10: Band/Orchestra
	     11: Composer
	     12: Lyricist/text writer
	     13: Recording location
	     14: During recording
	     15: During performance
	     16: Movie/video screen capture
	     17: A bright colored fish
	     18: Illustration
	     19: Band/artist logotype
	     20: Publisher/studio logotype

	    The  default is 3 (front cover).  More than one --picture option can
	    be specified to attach multiple pictures.  There  may  only  be  one
	    picture each of type 1 and 2 in a file.

	    media-type is optional and is now ignored.

	    description is optional. The default is an empty string.

	    The next part specifies the resolution and color information, but is
	    now ignored.

	    filename is the path to the picture file to be imported.

     --padding n
	    Reserve  n	extra  bytes  for metadata tags. This can make later tag
	    editing more efficient. Defaults to 512.

     --discard-comments
	    Don't propagate metadata tags from the input file.

     --discard-pictures
	    Don't propagate pictures or art from the input file.

   Input options
     --raw  Interpret input as raw PCM data without headers

     --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 big  endian,  0  for  little
	    (default: 0)

     --ignorelength
	    Ignore  the  data  length in Wave headers. Opusenc automatically ig-
	    nores the length when its implausible (very small or very large) but
	    some STDIN usage may still need this option to avoid truncation.

   Diagnostic options
     --serial n
	    Force use of a specific stream serial number, rather than  one  that
	    is randomly generated.  This is used to make the encoder determinis-
	    tic for testing and is not generally recommended.

     --save-range file
	    Save 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

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 160 kbit/s:
	    opusenc --bitrate 160 input.wav output.opus

     Record and send a live stream to an Icecast HTTP streaming server using og-
     gfwd:
	    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 de-
     signed 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.
     Interactive usage should use UDP/RTP directly.

AUTHORS
     Gregory Maxwell <greg@xiph.org>

SEE ALSO
     opusdec(1), opusinfo(1), oggfwd(1)

Xiph.Org Foundation		   2012-08-31			      opusenc(1)

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