"BROTLI" "1" "August 2017" "brotli 1.0.0" "User commands"
"NAME"
brotli - 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:
\(bu 2
"
--decompress --stdout --suffix=\.b" works the same as
\(bu 2
"
-d -s -S \.b" and
\(bu 2
"
-dsS \.b"
brotli has 3 operation modes:
\(bu 2
default mode is compression;
\(bu 2
--decompress option activates decompression mode;
\(bu 2
--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:
\(bu 2
when compressing, a suffix is appended to the source filename to
get the target filename
\(bu 2
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
\(bu 2
-#:
compression level (0-9); bigger values cause denser, but slower compression
\(bu 2
-c,
--stdout:
write on standard output
\(bu 2
-d,
--decompress:
decompress mode
\(bu 2
-f,
--force:
force output file overwrite
\(bu 2
-h,
--help:
display this help and exit
\(bu 2
-j,
--rm:
remove source file(s);
gzip (1)-like behaviour
\(bu 2
-k,
--keep:
keep source file(s);
zstd (1)-like behaviour
\(bu 2
-n,
--no-copy-stat:
do not copy source file(s) attributes
\(bu 2
-o FILE,
--output=FILE
output file; valid only if there is a single input entry
\(bu 2
-q NUM,
--quality=NUM:
compression level (0-11); bigger values cause denser, but slower compression
\(bu 2
-t,
--test:
test file integrity mode
\(bu 2
-v,
--verbose:
increase output verbosity
\(bu 2
-w NUM,
--lgwin=NUM:
set LZ77 window size (0, 10-24) (default: 22); window size is
(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
\(bu 2
-S SUF,
--suffix=SUF:
output file suffix (default:
\|\.br)
\(bu 2
-V,
--version:
display version and exit
\(bu 2
-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
