brotli(1) User Manual brotli(1)
NAME
brotli(1) -- brotli, unbrotli - compress or decompress files
SYNOPSIS
brotli [OPTION|FILE]...
unbrotli is equivalent to brotli --decompress
DESCRIPTION
brotli is a generic-purpose lossless compression algorithm that
compresses data using a combination of a modern variant of the LZ77
algorithm, Huffman coding and 2-nd order context modeling, with a
compression ratio comparable to the best currently available general-
purpose compression methods. It is similar in speed with deflate but
offers more dense compression.
brotli command line syntax similar to gzip (1) and zstd (1). Unlike
gzip (1), source files are preserved by default. It is possible to
remove them after processing by using the --rm option.
Arguments that look like "--name" or "--name=value" are options. Every
option has a short form "-x" or "-x value". Multiple short form
options could be coalesced:
o "--decompress --stdout --suffix=.b" works the same as
o "-d -s -S .b" and
o "-dsS .b"
brotli has 3 operation modes:
o default mode is compression;
o --decompress option activates decompression mode;
o --test option switches to integrity test mode; this option is
equivalent to "--decompress --stdout" except that the decompressed
data is discarded instead of being written to standard output.
Every non-option argument is a file entry. If no files are given or
file is "-", brotli reads from standard input. All arguments after
"--" are file entries.
Unless --stdout or --output is specified, files are written to a new
file whose name is derived from the source file name:
o when compressing, a suffix is appended to the source filename to get
the target filename
o when decompressing, a suffix is removed from the source filename to
get the target filename
Default suffix is .br, but it could be specified with --suffix option.
Conflicting or duplicate options are not allowed.
OPTIONS
o -#: compression level (0-9); bigger values cause denser, but slower
compression
o -c, --stdout: write on standard output
o -d, --decompress: decompress mode
o -f, --force: force output file overwrite
o -h, --help: display this help and exit
o -j, --rm: remove source file(s); gzip (1)-like behaviour
o -k, --keep: keep source file(s); zstd (1)-like behaviour
o -n, --no-copy-stat: do not copy source file(s) attributes
o -o FILE, --output=FILE output file; valid only if there is a single
input entry
o -q NUM, --quality=NUM: compression level (0-11); bigger values cause
denser, but slower compression
o -t, --test: test file integrity mode
o -v, --verbose: increase output verbosity
o -w NUM, --lgwin=NUM: set LZ77 window size (0, 10-24) (default: 24);
window size is (pow(2, NUM) - 16); 0 lets compressor decide over the
optimal value; bigger windows size improve density; decoder might
require up to window size memory to operate
o -D FILE, --dictionary=FILE: use FILE as raw (LZ77) dictionary; same
dictionary MUST be used both for compression and decompression
o -S SUF, --suffix=SUF: output file suffix (default: .br)
o -V, --version: display version and exit
o -Z, --best: use best compression level (default); same as "-q 11"
SEE ALSO
brotli file format is defined in RFC 7932
(https://www.ietf.org/rfc/rfc7932.txt).
brotli is open-sourced under the MIT License
(https://opensource.org/licenses/MIT).
Mailing list: https://groups.google.com/forum/#!forum/brotli
BUGS
Report bugs at: https://github.com/google/brotli/issues
brotli 1.0.9 August 14 2021 brotli(1)
brotli 1.1.0 - Generated Wed Dec 20 10:29:43 CST 2023