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