xenial (1) fdkaac.1.gz

Provided by: fdkaac_0.6.2-1_amd64 bug

NAME

       fdkaac - command line frontend for libfdk-aac encoder

SYNOPSIS

       fdkaac [OPTIONS] [FILE]

DESCRIPTION

       fdkaac reads linear PCM audio in either WAV, raw PCM, or CAF format, and encodes it into either M4A / AAC
       file.

       If the input file is "-", data is read from stdin.  Likewise, if the output file is "-", data is  written
       to stdout if one of streamable AAC transport formats are selected by -f.

       When CAF input and M4A output is used, tags in CAF file are copied into the resulting M4A.

OPTIONS

       -h, --help
              Show command help

       -o <FILE>
              Output filename.

       -p, --profile <n>
              Target profile (MPEG4 audio object type, AOT)

              2      MPEG-4 AAC LC (default)

              5      MPEG-4 HE-AAC (SBR)

              29     MPEG-4 HE-AAC v2 (SBR+PS)

              23     MPEG-4 AAC LD

              39     MPEG-4 AAC ELD

              129    MPEG-2 AAC LC

              132    MPEG-2 HE-AAC (SBR)

              156    MPEG-2 HE-AAC v2 (SBR+PS)

       -b, --bitrate <n>
              Target bitrate (for CBR)

       -m, --bitrate-mode <n>
              Bitrate  configuration  mode.   Available  VBR  quality  value depends on other parameters such as
              profile, sample rate, or number of channels.

              0      CBR (default)

              1-5    VBR (higher value -> higher bitrate)

       -w, --bandwidth <n>
              Frequency bandwidth (lowpass cut-off frequency) in Hz.  Available on AAC LC only.

       -a, --afterburner <n>
              Configure afterburner mode.  When enabled, quality is  increased  at  the  expense  of  additional
              computational workload.

              0      Off

              1      On (default)

       -L, --lowdelay-sbr <n>
              Configure SBR activity on AAC ELD.

              -1     Use ELD SBR auto configuration

              0      Disable SBR on ELD (default)

              1      Enable SBR on ELD

       -s, --sbr-ratio <n>
              Controls activation of downsampled SBR.

              0      Use lib default (default)

              1      Use downsampled SBR (default for ELD+SBR)

              2      Use dual-rate SBR (default for HE-AAC)

              Dual-rate SBR is what is normally used for HE-AAC, where AAC is encoded at half the sample rate of
              SBR, hence "dual rate".  On the other hand, downsampled SBR uses same sample rate for both of  AAC
              and SBR (single rate), therefore downsampled SBR typically consumes more bitrate.

              Downsampled  SBR  is  newly  introduced  feature  in  FDK  encoder  library  version 3.4.12.  When
              libfdk-aac in the system doesn't support this,  dual-rate  SBR  will  be  used.   When  available,
              dual-rate SBR is the default for HE-AAC and downsampled SBR is the default for ELD+SBR.

              Note  that  downsampled  HE-AAC  is  not  so  common as dual-rate one.  When downsampled HE-AAC is
              selected, fdkaac is forced to choose explicit hierarchical SBR signaling, which (at least)  iTunes
              doesn't accept.

       -f, --transport-format <n>
              Transport  format.  Tagging and gapless playback is only available on M4A.  Streaming to stdout is
              only available on others.

              0      M4A (default)

              1      ADIF

              2      ADTS

              6      LATM MCP=1

              7      LATM MCP=0

              10     LOAS/LATM (LATM within LOAS)

       -C, --adts-crc-check
              Add CRC protection on ADTS header.

       -h, --header-period <n>
              StreamMuxConfig/PCE repetition period in the transport layer.

       -G, --gapless-mode <n>
              Method to declare amount of encoder delay (and  padding)  in  M4A  container.   These  values  are
              mandatory for proper gapless playback on player side.

              0      iTunSMPB (default)

              1      ISO standard (edts and sgpd)

              2      Both

       --include-sbr-delay
              When specified, count SBR decoder delay in encoder delay.

              This is not iTunes compatible and will lead to gapless playback issue on LC only decoder, but this
              is the default behavior of FDK library.

              Whether counting SBR decoder delay in encoder delay or not result in  incompatibility  in  gapless
              playback.  You should pick which one will work for your favorite player.

              However,  it's better not to choose SBR at all if you want gapless playback.  LC doesn't have such
              issues.

       -I, --ignorelength
              Ignore length field of data chunk in input WAV file.

       -S, --silent
              Don't print progress messages.

       --moov-before-mdat
              Place moov box before mdat box in M4A container.  This option might be important for some hardware
              players, that are known to refuse moov box placed after mdat box.

       -R, --raw
              Regard input as raw PCM.

       --raw-channels <n>
              Specify number of channels of raw input (default: 2)

       --raw-rate <n>
              Specify sample rate of raw input (default: 44100)

       --raw-format <spec>
              Specify  sample  format  of  raw  input  (default:  "S16L").   Spec  is  as  the  following  (case
              insensitive):

              1st char -- type of sample
                     S (igned) | U (nsigned) | F (loat)

              2nd part (in digits)
                     bits per channel

              Last char -- endianness (can be omitted)
                     L (ittle, default) | B (ig)

       --title <string>
              Set title tag.

       --artist <string>
              Set artist tag.

       --album <string>
              Set album tag.

       --genre <string>
              Set genre tag.

       --date <string>
              Set date tag.

       --composer <string>
              Set composer tag.

       --grouping <string>
              Set grouping tag.

       --comment <string>
              Set comment tag.

       --album-artist <string>
              Set album artist tag.

       --track <number[/total]>
              Set track tag, with or without number of total tracks.

       --disk <number[/total]>
              Set disk tag, with or without number of total discs.

       --tempo <n>
              Set tempo (BPM) tag.

       --tag <fcc>:<value>
              Set    iTunes    predefined    tag    with    explicit    fourcc    key    and     value.      See
              <https://code.google.com/p/mp4v2/wiki/iTunesMetadata>  for  known  predefined  keys.  You can omit
              first char of fcc when it is the copyright sign.

       --tag-from-file <fcc>:<filename>
              Same as --tag, but set content of file as tag value.

       --long-tag <name>:<value>
              Set arbitrary tag as iTunes custom metadata.  Stored in com.apple.iTunes field.

       --tag-from-json <filename[?dot_notation]>
              Read tags from JSON.  By default, tags are assumed to be direct children of  the  root  object  in
              JSON.  Optionally you can specify arbitrary dot notation to locate the object containing tags.

EXAMPLES

       Encode WAV file into a M4A file.  MPEG4 AAC LC, VBR quality 3:

              fdkaac -m3 foo.wav

       Encode WAV file into a M4A file.  MPEG4 HE-AAC, bitrate 64kbps:

              fdkaac -p5 -b64 foo.wav

       Piping from ffmpeg (you need version supporting CAF output):

              ffmpeg -i foo.flac -f caf - | fdkaac -b128 - -o foo.m4a

       Import tags via json:

              ffprobe -v 0 -of json -show_format foo.flac >foo.json

              flac -dc foo.flac | \
              fdkaac - -ox.m4a -m2 --import-tag-from-json=foo.json?format.tags

NOTES

       Upto  32bit  integer  or  64bit  floating  point  format  is supported as input.  However, FDK library is
       implemented based on fixed point math and only  supports  16bit  integer  PCM.   Therefore,  be  wary  of
       clipping.  You might want to dither/noise shape beforehand when your input has higher resolution.

       Following channel layouts are supported by the encoder.

       1ch    C

       2ch    L R

       3ch    C L R

       4ch    C L R Cs

       5ch    C L R Ls Rs

       5.1ch  C L R Ls Rs LFE

       7.1ch (front)
              C Lc Rc L R Ls Rs LFE

       7.1ch (rear)
              C L R Ls Rs Rls Rrs LFE

AUTHORS

       nu774 <honeycomb77@gmail.com>.

                                                 November, 2013                                        FDKAAC(1)