1 .\" Automatically generated by Pandoc 1.17.1
3 .TH "FDKAAC" "1" "November, 2013" "" ""
7 fdkaac \- command line frontend for libfdk\-aac encoder
10 \f[B]fdkaac\f[] [OPTIONS] [FILE]
13 \f[B]fdkaac\f[] reads linear PCM audio in either WAV, raw PCM, or CAF
14 format, and encodes it into either M4A / AAC file.
16 If the input file is "\-", data is read from stdin.
17 Likewise, if the output file is "\-", data is written to stdout if one
18 of streamable AAC transport formats are selected by \f[B]\-f\f[].
20 When CAF input and M4A output is used, tags in CAF file are copied into
34 .B \-p, \-\-profile <n>
35 Target profile (MPEG4 audio object type, AOT)
39 MPEG\-4 AAC LC (default)
49 MPEG\-4 HE\-AAC v2 (SBR+PS)
64 .B \-b, \-\-bitrate <n>
65 Target bitrate (for CBR)
69 .B \-m, \-\-bitrate\-mode <n>
70 Bitrate configuration mode.
71 Available VBR quality value depends on other parameters such as profile,
72 sample rate, or number of channels.
81 VBR (higher value \-> higher bitrate)
86 .B \-w, \-\-bandwidth <n>
87 Frequency bandwidth (lowpass cut\-off frequency) in Hz.
88 Available on AAC LC only.
92 .B \-a, \-\-afterburner <n>
93 Configure afterburner mode.
94 When enabled, quality is increased at the expense of additional
95 computational workload.
109 .B \-L, \-\-lowdelay\-sbr <n>
110 Configure SBR activity on AAC ELD.
114 Use ELD SBR auto configuration
119 Disable SBR on ELD (default)
129 .B \-s, \-\-sbr\-ratio <n>
130 Controls activation of downsampled SBR.
134 Use lib default (default)
139 Use downsampled SBR (default for ELD+SBR)
144 Use dual\-rate SBR (default for HE\-AAC)
148 Dual\-rate SBR is what is normally used for HE\-AAC, where AAC is
149 encoded at half the sample rate of SBR, hence "dual rate".
150 On the other hand, downsampled SBR uses same sample rate for both of AAC
151 and SBR (single rate), therefore downsampled SBR typically consumes more
154 Downsampled SBR is newly introduced feature in FDK encoder library
156 When libfdk\-aac in the system doesn\[aq]t support this, dual\-rate SBR
158 When available, dual\-rate SBR is the default for HE\-AAC and
159 downsampled SBR is the default for ELD+SBR.
161 Note that downsampled HE\-AAC is not so common as dual\-rate one.
162 When downsampled HE\-AAC is selected, \f[B]fdkaac\f[] is forced to
163 choose explicit hierarchical SBR signaling, which (at least) iTunes
167 .B \-f, \-\-transport\-format <n>
169 Tagging and gapless playback is only available on M4A.
170 Streaming to stdout is only available on others.
199 LOAS/LATM (LATM within LOAS)
204 .B \-C, \-\-adts\-crc\-check
205 Add CRC protection on ADTS header.
209 .B \-h, \-\-header\-period <n>
210 StreamMuxConfig/PCE repetition period in the transport layer.
214 .B \-G, \-\-gapless\-mode <n>
215 Method to declare amount of encoder delay (and padding) in M4A
217 These values are mandatory for proper gapless playback on player side.
226 ISO standard (edts and sgpd)
236 .B \-\-include\-sbr\-delay
237 When specified, count SBR decoder delay in encoder delay.
240 This is not iTunes compatible and will lead to gapless playback issue on
241 LC only decoder, but this is the default behavior of FDK library.
243 Whether counting SBR decoder delay in encoder delay or not result in
244 incompatibility in gapless playback.
245 You should pick which one will work for your favorite player.
247 However, it\[aq]s better not to choose SBR at all if you want gapless
249 LC doesn\[aq]t have such issues.
252 .B \-I, \-\-ignorelength
253 Ignore length field of data chunk in input WAV file.
258 Don\[aq]t print progress messages.
262 .B \-\-moov\-before\-mdat
263 Place moov box before mdat box in M4A container.
264 This option might be important for some hardware players, that are known
265 to refuse moov box placed after mdat box.
270 Regard input as raw PCM.
274 .B \-\-raw\-channels <n>
275 Specify number of channels of raw input (default: 2)
280 Specify sample rate of raw input (default: 44100)
284 .B \-\-raw\-format <spec>
285 Specify sample format of raw input (default: "S16L").
286 \f[B]Spec\f[] is as the following (case insensitive):
289 .B 1st char \-\- type of sample
290 \f[B]S\f[] (igned) | \f[B]U\f[] (nsigned) | \f[B]F\f[] (loat)
294 .B 2nd part (in digits)
299 .B Last char \-\- endianness (can be omitted)
300 \f[B]L\f[] (ittle, default) | \f[B]B\f[] (ig)
305 .B \-\-title <string>
310 .B \-\-artist <string>
315 .B \-\-album <string>
320 .B \-\-genre <string>
330 .B \-\-composer <string>
335 .B \-\-grouping <string>
340 .B \-\-comment <string>
345 .B \-\-album\-artist <string>
346 Set album artist tag.
350 .B \-\-track <number[/total]>
351 Set track tag, with or without number of total tracks.
355 .B \-\-disk <number[/total]>
356 Set disk tag, with or without number of total discs.
365 .B \-\-tag <fcc>:<value>
366 Set iTunes predefined tag with explicit fourcc key and value.
367 See <https://code.google.com/p/mp4v2/wiki/iTunesMetadata> for known
369 You can omit first char of \f[B]fcc\f[] when it is the copyright sign.
373 .B \-\-tag\-from\-file <fcc>:<filename>
374 Same as \-\-tag, but set content of file as tag value.
378 .B \-\-long\-tag <name>:<value>
379 Set arbitrary tag as iTunes custom metadata.
380 Stored in com.apple.iTunes field.
384 .B \-\-tag\-from\-json <filename[?dot_notation]>
386 By default, tags are assumed to be direct children of the root object in
388 Optionally you can specify arbitrary dot notation to locate the object
394 Encode WAV file into a M4A file.
395 MPEG4 AAC LC, VBR quality 3:
399 fdkaac\ \-m3\ foo.wav
403 Encode WAV file into a M4A file.
404 MPEG4 HE\-AAC, bitrate 64kbps:
408 fdkaac\ \-p5\ \-b64\ foo.wav
412 Piping from \f[B]ffmpeg\f[] (you need version supporting CAF output):
416 ffmpeg\ \-i\ foo.flac\ \-f\ caf\ \-\ |\ fdkaac\ \-b128\ \-\ \-o\ foo.m4a
420 Import tags via json:
424 ffprobe\ \-v\ 0\ \-of\ json\ \-show_format\ foo.flac\ >foo.json
426 flac\ \-dc\ foo.flac\ |\ \\
427 fdkaac\ \-\ \-ox.m4a\ \-m2\ \-\-import\-tag\-from\-json=foo.json?format.tags
432 Upto 32bit integer or 64bit floating point format is supported as input.
433 However, FDK library is implemented based on fixed point math and only
434 supports 16bit integer PCM.
435 Therefore, be wary of clipping.
436 You might want to dither/noise shape beforehand when your input has
439 Following channel layouts are supported by the encoder.
472 C Lc Rc L R Ls Rs LFE
477 C L R Ls Rs Rls Rrs LFE
481 nu774 <honeycomb77@gmail.com>.