1FLAC(1)                                                                FLAC(1)
2
3
4

NAME

6       flac - Free Lossless Audio Codec
7

SYNOPSIS

9       flac  [ OPTIONS ] [ infile.wav | infile.rf64 | infile.aiff | infile.raw
10       | infile.flac | infile.oga | infile.ogg | - ... ]
11
12
13       flac [ -d | --decode | -t | --test | -a | --analyze ]  [  OPTIONS  ]  [
14       infile.flac | infile.oga | infile.ogg | - ... ]
15
16

DESCRIPTION

18       flac is a command-line tool for encoding, decoding, testing and analyz‐
19       ing FLAC streams.
20

OPTIONS

22       A summary of options is included below.  For  a  complete  description,
23       see the HTML documentation.
24
25   GENERAL OPTIONS
26       -v, --version
27              Show the flac version number
28
29       -h, --help
30              Show basic usage and a list of all options
31
32       -H, --explain
33              Show detailed explanation of usage and all options
34
35       -d, --decode
36              Decode (the default behavior is to encode)
37
38       -t, --test
39              Test  a  flac encoded file (same as -d except no decoded file is
40              written)
41
42       -a, --analyze
43              Analyze a FLAC encoded file (same as -d except an analysis  file
44              is written)
45
46       -c, --stdout
47              Write output to stdout
48
49       -s, --silent
50              Silent  mode  (do  not write runtime encode/decode statistics to
51              stderr)
52
53       --totally-silent
54              Do not print anything of any kind, including warnings or errors.
55              The  exit code will be the only way to determine successful com‐
56              pletion.
57
58       --no-utf8-convert
59              Do not convert tags from local charset to UTF-8.  This is useful
60              for  scripts, and setting tags in situations where the locale is
61              wrong.  This option must appear before any tag options!
62
63       -w, --warnings-as-errors
64              Treat all warnings as errors (which cause flac to terminate with
65              a non-zero exit code).
66
67       -f, --force
68              Force  overwriting of output files.  By default, flac warns that
69              the output file already exists and continues to the next file.
70
71       -o filename, --output-name=filename
72              Force the output file name (usually flac just changes the exten‐
73              sion).   May  only be used when encoding a single file.  May not
74              be used in conjunction with --output-prefix.
75
76       --output-prefix=string
77              Prefix each output file name with the given string.  This can be
78              useful  for encoding or decoding files to a different directory.
79              Make sure if your string is a path name  that  it  ends  with  a
80              trailing `/' (slash).
81
82       --delete-input-file
83              Automatically delete the input file after a successful encode or
84              decode.  If there was an error (including a  verify  error)  the
85              input file is left intact.
86
87       --preserve-modtime
88              Output  files  have  their  timestamps/permissions  set to match
89              those of their inputs (this is default).  Use --no-preserve-mod‐
90              time to make output files have the current time and default per‐
91              missions.
92
93       --keep-foreign-metadata
94              If encoding, save WAVE, RF64, or AIFF non-audio chunks  in  FLAC
95              metadata.   If decoding, restore any saved non-audio chunks from
96              FLAC metadata when writing the decoded file.   Foreign  metadata
97              cannot be transcoded, e.g. WAVE chunks saved in a FLAC file can‐
98              not be restored when decoding to AIFF.  Input and output must be
99              regular files (not stdin or stdout).
100
101       --skip={#|mm:ss.ss}
102              Skip  over the first number of samples of the input.  This works
103              for both encoding and decoding, but not testing.   The  alterna‐
104              tive  form mm:ss.ss can be used to specify minutes, seconds, and
105              fractions of a second.
106
107       --until={#|[+|-]mm:ss.ss}
108              Stop at the given sample number for each input file.  This works
109              for both encoding and decoding, but not testing.  The given sam‐
110              ple number is not included in the decoded output.  The  alterna‐
111              tive  form mm:ss.ss can be used to specify minutes, seconds, and
112              fractions of a second.  If a `+' (plus) sign is  at  the  begin‐
113              ning,  the  --until point is relative to the --skip point.  If a
114              `-' (minus) sign is at the beginning, the --until point is rela‐
115              tive to end of the audio.
116
117       --ogg  When  encoding, generate Ogg FLAC output instead of native FLAC.
118              Ogg FLAC streams are FLAC streams wrapped in  an  Ogg  transport
119              layer.   The  resulting file should have an '.oga' extension and
120              will still be decodable by flac.
121
122              When decoding, force the input to be treated as Ogg FLAC.   This
123              is useful when piping input from stdin or when the filename does
124              not end in '.oga' or '.ogg'.
125
126       --serial-number=#
127              When used with --ogg, specifies the serial number to use for the
128              first  Ogg FLAC stream, which is then incremented for each addi‐
129              tional stream.  When encoding and no  serial  number  is  given,
130              flac  uses a random number for the first stream, then increments
131              it for each additional stream.  When decoding and no  number  is
132              given, flac uses the serial number of the first page.
133
134   ANALYSIS OPTIONS
135       --residual-text
136              Includes  the  residual  signal in the analysis file.  This will
137              make the file very big, much larger than even the decoded file.
138
139       --residual-gnuplot
140              Generates a gnuplot file for every subframe; each file will con‐
141              tain  the residual distribution of the subframe.  This will cre‐
142              ate a lot of files.
143
144   DECODING OPTIONS
145       --cue=[#.#][-[#.#]]
146              Set the beginning and ending cuepoints to decode.  The  optional
147              first  #.#  is  the track and index point at which decoding will
148              start; the default is the beginning of the stream.  The optional
149              second  #.#  is the track and index point at which decoding will
150              end; the default is the end of the stream.  If the cuepoint does
151              not  exist,  the  closest one before it (for the start point) or
152              after it (for the end point)  will  be  used.   If  those  don't
153              exist,  the  start of the stream (for the start point) or end of
154              the stream (for the end point) will be used.  The cuepoints  are
155              merely  translated  into  sample numbers then used as --skip and
156              --until.  A CD  track  can  always  be  cued  by,  for  example,
157              --cue=9.1-10.1 for track 9, even if the CD has no 10th track.
158
159       -F, --decode-through-errors
160              By  default  flac  stops  decoding with an error and removes the
161              partially decoded file if it encounters a bitstream error.  With
162              -F,  errors are still printed but flac will continue decoding to
163              completion.  Note that errors may cause the decoded audio to  be
164              missing some samples or have silent sections.
165
166       --apply-replaygain-which-is-not-lossless[=<specification>]
167              Applies ReplayGain values while decoding.
168
169              WARNING:  THIS IS NOT LOSSLESS.  DECODED AUDIO WILL NOT BE IDEN‐
170              TICAL TO THE ORIGINAL WITH THIS OPTION.
171
172              The equals sign and <specification> is  optional.   If  omitted,
173              the default is 0aLn1.
174
175              The  <specification>  is a shorthand notation for describing how
176              to apply ReplayGain.  All components are optional but  order  is
177              important.   '[]' means 'optional'.  '|' means 'or'.  '{}' means
178              required.  The format is:
179
180              [<preamp>][a|t][l|L][n{0|1|2|3}]
181
182              preamp A floating point number in dB.   This  is  added  to  the
183                     existing gain value.
184
185              a|t    Specify  'a'  to  use  the  album gain, or 't' to use the
186                     track gain.  If tags for the preferred kind (album/track)
187                     do  not  exist  but  tags for the other (track/album) do,
188                     those will be used instead.
189
190              l|L    Specify 'l' to peak-limit the output, so that the Replay‐
191                     Gain  peak value is full-scale.  Specify 'L' to use a 6dB
192                     hard limiter that kicks in  when  the  signal  approaches
193                     full-scale.
194
195              n{0|1|2|3}
196                     Specify  the amount of noise shaping.  ReplayGain synthe‐
197                     sis happens in floating point;  the  result  is  dithered
198                     before  converting  back  to  integer.  This quantization
199                     adds noise.  Noise shaping tries to move the noise  where
200                     you  won't  hear it as much.  0 means no noise shaping, 1
201                     means 'low', 2 means 'medium', 3 means 'high'.
202
203       For example, the default of 0aLn1 means 0dB preamp, use album gain, 6dB
204       hard limit, low noise shaping.
205
206       --apply-replaygain-which-is-not-lossless=3  means 3dB preamp, use album
207       gain, no limiting, no noise shaping.
208
209       flac uses the ReplayGain tags for the calculation.  If  a  stream  does
210       not  have the required tags or they can't be parsed, decoding will con‐
211       tinue with a warning, and no ReplayGain is applied to that stream.
212
213   ENCODING OPTIONS
214       -V, --verify
215              Verify a correct encoding by decoding the output in parallel and
216              comparing to the original
217
218       --lax  Allow  encoder to generate non-Subset files.  The resulting FLAC
219              file may not be streamable or might have trouble being played in
220              all  players  (especially  hardware devices), so you should only
221              use this option in  combination  with  custom  encoding  options
222              meant for archival.
223
224       --replay-gain
225              Calculate ReplayGain values and store them as FLAC tags, similar
226              to vorbisgain.  Title gains/peaks  will  be  computed  for  each
227              input  file,  and  an  album  gain/peak will be computed for all
228              files.  All input files must have the  same  resolution,  sample
229              rate,  and  number  of channels.  Only mono and stereo files are
230              allowed, and the sample rate must be one of 8, 11.025,  12,  16,
231              22.05,  24, 32, 44.1, or 48 kHz.  Also note that this option may
232              leave a few extra bytes in a PADDING block as the exact size  of
233              the  tags is not known until all files are processed.  Note that
234              this option cannot be used  when  encoding  to  standard  output
235              (stdout).
236
237       --cuesheet=filename
238              Import  the given cuesheet file and store it in a CUESHEET meta‐
239              data block.  This option may only be used when encoding a single
240              file.   A  seekpoint  will  be added for each index point in the
241              cuesheet to the SEEKTABLE unless --no-cued-seekpoints is  speci‐
242              fied.
243
244       --picture={FILENAME|SPECIFICATION}
245              Import a picture and store it in a PICTURE metadata block.  More
246              than one --picture command can be specified.  Either a  filename
247              for  the  picture file or a more complete specification form can
248              be used.  The SPECIFICATION is a string whose  parts  are  sepa‐
249              rated  by  | (pipe) characters.  Some parts may be left empty to
250              invoke  default  values.   FILENAME  is   just   shorthand   for
251              "||||FILENAME".  The format of SPECIFICATION is
252
253              [TYPE]|[MIME-TYPE]|[DESCRIPTION]|[WIDTHxHEIGHTxDEPTH[/COL‐
254              ORS]]|FILE
255
256              TYPE is optional; it is a number from one of:
257
258              0: Other
259
260              1: 32x32 pixels 'file icon' (PNG only)
261
262              2: Other file icon
263
264              3: Cover (front)
265
266              4: Cover (back)
267
268              5: Leaflet page
269
270              6: Media (e.g. label side of CD)
271
272              7: Lead artist/lead performer/soloist
273
274              8: Artist/performer
275
276              9: Conductor
277
278              10: Band/Orchestra
279
280              11: Composer
281
282              12: Lyricist/text writer
283
284              13: Recording Location
285
286              14: During recording
287
288              15: During performance
289
290              16: Movie/video screen capture
291
292              17: A bright coloured fish
293
294              18: Illustration
295
296              19: Band/artist logotype
297
298              20: Publisher/Studio logotype
299
300              The default is 3 (front cover).  There may only be  one  picture
301              each of type 1 and 2 in a file.
302
303              MIME-TYPE  is  optional; if left blank, it will be detected from
304              the file.  For best compatibility  with  players,  use  pictures
305              with  MIME type image/jpeg or image/png.  The MIME type can also
306              be --> to mean that FILE is actually a URL to an  image,  though
307              this use is discouraged.
308
309              DESCRIPTION is optional; the default is an empty string.
310
311              The next part specfies the resolution and color information.  If
312              the MIME-TYPE is image/jpeg, image/png, or  image/gif,  you  can
313              usually leave this empty and they can be detected from the file.
314              Otherwise, you must specify the width in pixels, height in  pix‐
315              els,  and  color  depth  in  bits-per-pixel.   If  the image has
316              indexed colors you should also  specify  the  number  of  colors
317              used.   When  manually  specified, it is not checked against the
318              file for accuracy.
319
320              FILE is the path to the picture file to be imported, or the  URL
321              if MIME type is -->
322
323              For  example,  "|image/jpeg|||../cover.jpg"  will embed the JPEG
324              file at ../cover.jpg, defaulting to type 3 (front cover) and  an
325              empty  description.   The  resolution  and  color  info  will be
326              retrieved from the file itself.
327
328              The                                                specification
329              "4|-->|CD|320x300x24/173|http://blah.blah/backcover.tiff"   will
330              embed the given URL, with type 4 (back cover), description "CD",
331              and  a  manually  specified  resolution of 320x300, 24 bits-per-
332              pixel, and 173 colors.  The file at the URL will not be fetched;
333              the URL itself is stored in the PICTURE metadata block.
334
335       --sector-align
336              Align encoding of multiple CD format files on sector boundaries.
337              See the HTML documentation for more information.  This option is
338              DEPRECATED and may not exist in future versions of flac.
339
340       --ignore-chunk-sizes
341              When  encoding  to flac, ignore the file size headers in WAV and
342              AIFF files to attempt to work around problems with over-sized or
343              malformed files.
344
345              WAV  and  AIFF files both have an unsigned 32 bit numbers in the
346              file header which specifes the length of audio data. Since  this
347              number is unsigned 32 bits, that limits the size of a valid file
348              to being just over 4 Gigabytes. Files larger than this are  mal-
349              formed, but should be read correctly using this option.
350
351       -S {#|X|#x|#s}, --seekpoint={#|X|#x|#s}
352              Include a point or points in a SEEKTABLE.  Using #, a seek point
353              at that sample number is added.  Using X, a placeholder point is
354              added at the end of a the table.  Using #x, # evenly spaced seek
355              points will be added, the first being at sample 0.  Using #s,  a
356              seekpoint will be added every # seconds (# does not have to be a
357              whole number; it can be, for example, 9.5, meaning  a  seekpoint
358              every  9.5 seconds).  You may use many -S options; the resulting
359              SEEKTABLE will be the unique-ified union  of  all  such  values.
360              With  no  -S options, flac defaults to '-S 10s'.  Use --no-seek‐
361              table for no SEEKTABLE.  Note: '-S #x' and '-S #s' will not work
362              if  the  encoder can't determine the input size before starting.
363              Note: if you use '-S #' and # is >= samples in the input,  there
364              will  be  either  no  seek  point  entered (if the input size is
365              determinable before encoding starts) or a placeholder point  (if
366              input size is not determinable).
367
368       -P #, --padding=#
369              Tell  the encoder to write a PADDING metadata block of the given
370              length (in bytes) after the STREAMINFO block.  This is useful if
371              you  plan  to  tag  the  file  later  with an APPLICATION block;
372              instead of having to rewrite  the  entire  file  later  just  to
373              insert  your  block,  you  can  write  directly over the PADDING
374              block.  Note that the total length of the PADDING block will  be
375              4  bytes  longer than the length given because of the 4 metadata
376              block header bytes.  You can force no PADDING block at all to be
377              written  with  --no-padding.  The encoder writes a PADDING block
378              of 8192 bytes by default (or 65536  bytes  if  the  input  audio
379              stream is more that 20 minutes long).
380
381       -T FIELD=VALUE, --tag=FIELD=VALUE
382              Add  a  FLAC tag.  The comment must adhere to the Vorbis comment
383              spec; i.e. the FIELD must contain only legal characters,  termi‐
384              nated  by  an  'equals' sign.  Make sure to quote the comment if
385              necessary.  This option may appear more than once to add several
386              comments.  NOTE: all tags will be added to all encoded files.
387
388       --tag-from-file=FIELD=FILENAME
389              Like  --tag,  except  FILENAME  is a file whose contents will be
390              read verbatim to set the tag value.  The contents will  be  con‐
391              verted  to  UTF-8  from  the local charset.  This can be used to
392              store   a    cuesheet    in    a    tag    (e.g.     --tag-from-
393              file="CUESHEET=image.cue").   Do not try to store binary data in
394              tag fields!  Use APPLICATION blocks for that.
395
396       -b #, --blocksize=#
397              Specify the block size in samples.  Subset streams must use  one
398              of  192,  576, 1152, 2304, 4608, 256, 512, 1024, 2048, 4096 (and
399              8192 or 16384 if the sample rate is >48kHz).
400
401       -m, --mid-side
402              Try mid-side coding for each frame (stereo input only)
403
404       -M, --adaptive-mid-side
405              Adaptive mid-side coding for all frames (stereo input only)
406
407       -0..-8, --compression-level-0..--compression-level-8
408              Fastest compression..highest compression (default is -5).  These
409              are synonyms for other options:
410
411              -0, --compression-level-0
412                     Synonymous with -l 0 -b 1152 -r 3 --no-mid-side
413
414              -1, --compression-level-1
415                     Synonymous with -l 0 -b 1152 -M -r 3
416
417              -2, --compression-level-2
418                     Synonymous with -l 0 -b 1152 -m -r 3
419
420              -3, --compression-level-3
421                     Synonymous with -l 6 -b 4096 -r 4 --no-mid-side
422
423              -4, --compression-level-4
424                     Synonymous with -l 8 -b 4096 -M -r 4
425
426              -5, --compression-level-5
427                     Synonymous with -l 8 -b 4096 -m -r 5
428
429              -6, --compression-level-6
430                     Synonymous  with  -l  8  -b 4096 -m -r 6 -A tukey(0.5) -A
431                     partial_tukey(2)
432
433              -7, --compression-level-7
434                     Synonymous with -l 12 -b 4096 -m -r 6  -A  tukey(0.5)  -A
435                     partial_tukey(2)
436
437              -8, --compression-level-8
438                     Synonymous  with  -l  12 -b 4096 -m -r 6 -A tukey(0.5) -A
439                     partial_tukey(2) -A punchout_tukey(3)
440
441       --fast Fastest compression.  Currently synonymous with -0.
442
443       --best Highest compression.  Currently synonymous with -8.
444
445       -e, --exhaustive-model-search
446              Do exhaustive model search (expensive!)
447
448       -A function, --apodization=function
449              Window audio data with  given  the  apodization  function.   The
450              functions  are: bartlett, bartlett_hann, blackman, blackman_har‐
451              ris_4term_92db, connes, flattop, gauss(STDDEV),  hamming,  hann,
452              kaiser_bessel,  nuttall,  rectangle,  triangle,  tukey(P),  par‐
453              tial_tukey(n[/ov[/P]]), punchout_tukey(n[/ov[/P]]), welch.
454
455              For gauss(STDDEV), STDDEV  is  the  standard  deviation  (0<STD‐
456              DEV<=0.5).
457
458              For  tukey(P),  P  specifies  the fraction of the window that is
459              tapered (0<=P<=1; P=0 corresponds to "rectangle" and P=1  corre‐
460              sponds to "hann").
461
462              For  partial_tukey(n) and punchout_tukey(n), n apodization func‐
463              tions are added that span different parts of each block.  Values
464              of  2  to 6 seem to yield sane results. If necessary, an overlap
465              can be specified, as can be the  taper  parameter,  for  example
466              partial_tukey(2/0.2)  or  partial_tukey(2/0.2/0.5). ov should be
467              smaller than 1 and can be negative.
468
469              Please note that P, STDDEV and ov  are  locale  specific,  so  a
470              comma as decimal separator might be required instead of a dot.
471
472              More  than  one  -A option (up to 32) may be used.  Any function
473              that is specified erroneously is silently dropped.  The  encoder
474              chooses  suitable defaults in the absence of any -A options; any
475              -A option specified replaces the default(s).
476
477              When more than one function is specified, then  for  every  sub‐
478              frame  the  encoder  will try each of them separately and choose
479              the window that results in  the  smallest  compressed  subframe.
480              Multiple functions can greatly increase the encoding time.
481
482       -l #, --max-lpc-order=#
483              Specifies  the maximum LPC order. This number must be <= 32. For
484              Subset streams, it must be <=12 if the sample rate  is  <=48kHz.
485              If  0,  the  encoder will not attempt generic linear prediction,
486              and use only fixed predictors. Using fixed predictors is  faster
487              but usually results in files being 5-10% larger.
488
489       -p, --qlp-coeff-precision-search
490              Do  exhaustive  search  of  LP  coefficient quantization (expen‐
491              sive!).  Overrides -q; does nothing if using -l 0
492
493       -q #, --qlp-coeff-precision=#
494              Precision of the quantized linear-predictor coefficients,  0  =>
495              let encoder decide (min is 5, default is 0)
496
497       -r [#,]#, --rice-partition-order=[#,]#
498              Set the [min,]max residual partition order (0..15). min defaults
499              to 0 if unspecified.  Default is -r 5.
500
501   FORMAT OPTIONS
502       --endian={big|little}
503              Set the byte order for samples
504
505       --channels=#
506              Set number of channels.
507
508       --bps=#
509              Set bits per sample.
510
511       --sample-rate=#
512              Set sample rate (in Hz).
513
514       --sign={signed|unsigned}
515              Set the sign of samples (the default is signed).
516
517       --input-size=#
518              Specify the size of the raw input in bytes.  If you are encoding
519              raw  samples from stdin, you must set this option in order to be
520              able to use --skip, --until, --cuesheet, or other  options  that
521              need  to  know  the  size  of the input beforehand.  If the size
522              given is greater than what is found in  the  input  stream,  the
523              encoder  will  complain about an unexpected end-of-file.  If the
524              size given is less, samples will be truncated.
525
526       --force-raw-format
527              Force input (when encoding) or  output  (when  decoding)  to  be
528              treated as raw samples (even if filename ends in .wav).
529
530       --force-aiff-format
531              Force  the  decoder  to  output AIFF format.  This option is not
532              needed if the output filename (as set by -o) ends with  .aif  or
533              .aiff.   Also,  this  option  has  no effect when encoding since
534              input AIFF is auto-detected.
535
536       --force-rf64-format
537              Force the decoder to output RF64 format.   This  option  is  not
538              needed  if  the  output filename (as set by -o) ends with .rf64.
539              Also, this option has no effect when encoding since  input  RF64
540              is auto-detected.
541
542       --force-wave64-format
543              Force  the  decoder to output Wave64 format.  This option is not
544              needed if the output filename (as set by  -o)  ends  with  .w64.
545              Also, this option has no effect when encoding since input Wave64
546              is auto-detected.
547
548   NEGATIVE OPTIONS
549       --no-adaptive-mid-side
550
551       --no-cued-seekpoints
552
553       --no-decode-through-errors
554
555       --no-delete-input-file
556
557       --no-preserve-modtime
558
559       --no-keep-foreign-metadata
560
561       --no-exhaustive-model-search
562
563       --no-force
564
565       --no-lax
566
567       --no-mid-side
568
569       --no-ogg
570
571       --no-padding
572
573       --no-qlp-coeff-prec-search
574
575       --no-replay-gain
576
577       --no-residual-gnuplot
578
579       --no-residual-text
580
581       --no-sector-align
582
583       --no-seektable
584
585       --no-silent
586
587       --no-verify
588
589       --no-warnings-as-errors
590              These flags can be used to invert the sense of the corresponding
591              normal option.
592

SEE ALSO

594       metaflac(1)
595
596       The  programs are documented fully by HTML format documentation, avail‐
597       able in /usr/share/doc/libflac-doc/html on Debian GNU/Linux systems.
598

AUTHOR

600       This  manual   page   was   initially   written   by   Matt   Zimmerman
601       <mdz@debian.org>  for  the  Debian GNU/Linux system (but may be used by
602       others). It has been kept up-to-date by the Xiph.org Foundation.
603
604
605
606                                  2013/09/18                           FLAC(1)
Impressum