FLAC(1)

NAME
flac - Free Lossless Audio Codec

SYNOPSIS
flac [ OPTION] infile ...

DESCRIPTION

This manual page documents briefly the flac command.

This manual page was written for the Debian GNU/Linux distribution because the original program does not have a manual page. Instead, it has documentation in HTML format; see below.

OPTIONS

A summary of options is included below. For a complete description, see the HTML documentation.

  GENERIC OPTIONS

-H  Show detailed help screen

-d  Decode (default behavior is encode)

-c  Encode from standard input, or decode to standard output

-t  Test a flac encoded file (same as -d except no decoded file is written)

-a  Analyze a flac encoded file (same as -d except an analysis file is written)

-s  Silent mode (do not write runtime encode/decode statistics to stdout)

-o filename
    Force the output file name (usually flac just changes the extension). May only be used when encoding a single file. May not be used in conjunction with --output-prefix.

--output-prefix string
    Prefix each output file name with the given string. This can be useful for encoding/decoding files to a different directory. Make sure if your string is a path name that it ends with a trailing `/' (slash).

--delete-input-file
    Automatically delete the input file after a successful encode or decode. If there was an error (including a verify error) the input file is left intact.

--skip samples
    Skip the specified number of samples at the beginning of the input file (can be used for both encoding and decoding)

  ANALYSIS OPTIONS

--a-rtext
    Includes the residual signal in the analysis file. This will make the file very big, much larger than even the decoded file.

--a-rgp
    Generates a gnuplot file for every subframe; each file will contain the residual distribution of the subframe. This will create a lot of files.

  ENCODING OPTIONS

--ogg
    When encoding, generate Ogg-FLAC output instead of native-FLAC. Ogg-FLAC streams are FLAC streams wrapped in an Ogg transport layer. The resulting file should have an '.ogg' extension and will still be decodable by flac. When decoding, force the input to be treated as Ogg-FLAC. This is useful when piping input from stdin or when the filename does not end in '.ogg'.

--lax
    Allow encoder to generate non-Subset files.

--sector-align
    Align encoding of multiple CD format WAVE files on sector boundaries. See the HTML documentation for more information.

-S { # | X | #x }
    Include a point or points in a SEEKTABLE. Using #, a seek point at that sample number is added. Using X, a placeholder point is added at the end of a the table. Using #x, # evenly spaced seek points will be added, the first being at sample 0. You may use many -S options; the resulting SEEKTABLE will be the unique-ified union of all such values. With no -S options, flac defaults to '-S 100x'. Use -S- for no SEEKTABLE. Note: '-S #x' will not work if the encoder can't determine the input size before starting. Note: if you use '-S #' and # is >= samples in the input, there will be either no seek point entered (if the input size is determinable before encoding starts) or a placeholder point (if input size is not determinable).

-P bytes
    Tell the encoder to write a PADDING metadata block of the given length (in bytes) after the STREAMINFO block. -P 0 implies no PADDING block, which is the default. This is useful if you plan to tag the file later with an APPLICATION block; instead of having to rewrite the entire file later just to insert your block, you can write directly over the PADDING block.

-b blocksize
    Default is 1152 for -l 0, else 4608; must be 192/576/1152/2304/4608/256/512/1024/2048/4096/8192/16384/32768 (unless --lax is used)

-m  Try mid-side coding for each frame (stereo input only)

-M  Loose mid-side coding for all frames (stereo input only)

-0..-8
    Fastest compression..highest compression (default is -5). These are synonyms for other options:

    -0  Synonymous with -l 0 -b 1152 -r 2,2

    -1  Synonymous with -l 0 -b 1152 -M -r 2,2

    -2  Synonymous with -l 0 -b 1152 -m -r 3

    -3  Synonymous with -l 6 -b 4608 -r 3,3

    -4  Synonymous with -l 8 -b 4608 -M -r 3,3

    -5  Synonymous with -l 8 -b 4608 -m -r 3,3

    -6  Synonymous with -l 8 -b 4608 -m -r 4

    -7  Synonymous with -l 8 -b 4608 -m -e -r 6

    -8  Synonymous with -l 12 -b 4608 -m -e -r 6

-e  Do exhaustive model search (expensive!)

-E  Do escape coding in the entropy coder. This causes the encoder to use an unencoded representation of the residual in a partition if it is smaller. It increases the runtime and usually results in an improvement of less than 1%.

-l max_lpc_order
    0 => use only fixed predictors

-p  Do exhaustive search of LP coefficient quantization (expensive!). Overrides -q, does nothing if using -l 0

-q bits
    Precision of the quantized linear-predictor coefficients, 0 => let encoder decide (min is 5, default is 0)

-r [level,]level
    Set the [min,]max residual partition order (0..16). min defaults to 0 if unspecified. Default is -r 3,3.

-R #
    Set the Rice parameter search distance. Default is 0.

-V  Verify a correct encoding by decoding the output in parallel and comparing to the original

-S- -m- -M- -e- -E- -p- -V- --delete-input-file- --lax- --ogg-
    These flags can be used to invert the sense of the corresponding normal option.

  FORMAT OPTIONS

-fb Big-endian byte order

-fl Little-endian byte order

-fc channels
    Set number of channels.

-fp bits_per_sample
    Set bits per sample.

-fs sample_rate
    Set sample rate (in Hz).

-fu Unsigned samples (default is signed)

-fr Force to raw format (even if filename ends in .wav).

SEE ALSO

The programs are documented fully by HTML format documentation, available in /usr/share/doc/flac/html on Debian GNU/Linux systems.

AUTHOR

This manual page was written by Matt Zimmerman <mdz@debian.org> for the Debian GNU/Linux system (but may be used by others).