3 mp3dec, mp3enc, oggdec, oggenc, flacdec, flacenc, sundec, wavdec, pcmconv, mixfs \- decode and encode audio files
56 .I "long or silly options"
104 These programs decode and encode various audio formats from and to
105 16-bit stereo PCM (little endian). The decoders read the compressed
106 audio data from standard input and produce PCM on standard output at
107 a sampling frequency of 44.1KHz.
110 decodes MPEG audio (layer 1, 2 and 3). The
112 option enables debug output to standard error.
120 but decode OGG Vorbis, FLAC lossless audio, Sun audio and RIFF wave.
122 .TF "\fB-s seconds \fP"
125 seek to a specific position in seconds before decoding.
128 The encoders read PCM on standard input and produce compressed audio
135 produce FLAC, OGG Vorbis and MP3 audio. For
137 the MP3 file will use `constant bit-rate' (CBR) encoding by default,
138 but that can be changed via
140 (average bitrate desired, ABR)
143 (variable bitrate, VBR).
148 accept raw PCM in the same byte order as
160 in Kb/s for VBR, default 32Kb/s.
162 set the exact bitrate in Kb/s, which defaults to 128Kb/s.
167 in Kb/s for VBR, default 256Kb/s.
183 forces mid/side stereo on all frames.
186 add CRC error protection (adds an additional 16 bits per frame to the stream).
187 This seems to break playback.
190 sets output quality to
199 set sampling frequency of input file (in KHz) to
204 use variable bitrate (VBR) encoding
207 set quality setting for VBR to
212 0 produces highest-quality and largest files, and
213 9 produces lowest-quality and smallest files.
215 .TF "\fB--resample sfreq \fP"
220 desired in Kb/s, instead of setting quality,
221 and generates ABR encoding.
223 .BI --resample " sfreq"
224 set sampling frequency of output file (in KHz) to
226 default is input sfreq.
228 .BI --mp3input " input"
240 mark as non-original (i.e. do not set the original bit)
246 disable sfb=21 cutoff
253 allow channels to have different blocktypes
256 disable Xing VBR informational tag
259 autoconvert from stereo to mono file for mono encoding
262 force byte-swapping of input (see
267 don't print progress report, VBR histograms
270 only use the ATH for masking
273 disable VBR histogram display
276 experimental voice mode
279 is a helper program used to convert various PCM sample formats. The
283 options specify the input and output format
287 is a concatenated string of the following parts:
290 sample format is little-endian signed integer where
292 specifies the number of bits
295 unsigned little-endian integer format
298 signed big-endian integer format
301 unsigned big-endian integer format
304 floating point format where
306 has to be 32 or 64 for single- or double-precision
315 specifies the number of channels
318 gives the samplerate in Hz
320 The program reads samples from standard
321 input converting the data and writes the result to standard output
322 until it reached end of file or, if
324 was given, a number of
326 bytes have been consumed from input.
329 is a fileserver serving a single
331 file which allows simultaneous playback of audio streams. When
334 and mixes the audio samples that are written to it.
337 can be given with the
339 option which gets posted to
349 A alternative mountpoint
351 can be specified with the
358 debug messages to be written to file-descriptor 2.
364 audio/mp3dec <foo.mp3 >/dev/audio
369 file as highest-quality MP3.
372 audio/mp3enc -q 0 -b 320 <foo.wav >foo.mp3
375 Create a fixed 128Kb/s MP3 file from a
380 audio/mp3enc -h <foo.wav >foo.mp3
383 Streaming from stereo 44.1KHz raw PCM data, encoding mono at 16KHz
388 dd -conv swab | audio/mp3enc -a -r -m m --resample 16 -b 24
391 .B /sys/src/cmd/audio
396 .B http://www.underbit.com/products/mad/
398 .B http://xiph.org/doc/
400 .B http://flac.sourceforge.net/documentation.html
403 first appeared in 9front (December, 2012).
405 first appeared in 9front (December, 2013).
407 first appeared in 9front (January, 2021).