brotli(1)

💖 brotli(1) — the User Manual, bestie edition 💖

okay so hi. this is the manual for brotli(1), and yes there's also brcat and unbrotli in the mix — they're the same tool wearing different outfits. buckle up, we're gonna make your files smol. 🎀

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✨ NAME ✨

brotli(1) — aka brotli, brcat, unbrotli — compress or decompress files. that's the whole job. iconic honestly. 💅

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🌸 SYNOPSIS 🌸

brotli [OPTION|FILE]...

• brcat is literally just brotli --decompress --concatenated --stdout
• unbrotli is literally just brotli --decompress

same girl, different vibes. 🦋

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🫶 DESCRIPTION 🫶

so brotli is a generic-purpose lossless compression algorithm — lossless meaning nothing gets thrown away, your data comes back exactly how it left. it squishes your data using a combo of a modern variant of the LZ77 algorithm, Huffman coding, and 2nd order context modeling. the compression ratio? comparable to the best currently available general-purpose compression methods. no cap. it's similar in speed with deflate but offers more dense compression. so like, same-ish speed, tinier output. we love a glow-up. ✨

the brotli command line syntax is similar to gzip(1) and zstd(1). but here's the plot twist — unlike gzip(1), source files are preserved by default. your originals stay safe, periodt. and if you do want them gone after processing, you can remove them with the --rm option. your call, bestie. 💜

arguments that look like --name or --name=value are options. every option has a short form -x or -x value. and multiple short form options could be coalesced, which is so satisfying:

• --decompress --stdout --suffix=.b works the same as
• -d -s -S .b and
• -dsS .b

look at that last one. compressed and cunty. 😌

brotli has 3 operation modes:

• default mode is compression (the main character)
• --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. so it checks the vibe and then ghosts the output. 💀

every non-option argument is a file entry. if no files are given, or if the 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 the --suffix option.

⚠️ conflicting or duplicate options are not allowed. don't try it. the tool said no. 🙈

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👑 OPTIONS 👑

• -# — compression level (0-9); bigger values cause denser, but slower compression. denser = more slay, but she takes her time. 🐌✨
• -c, --stdout — write on standard output. no new files, just vibes to your terminal. 🖥️
• -d, --decompress — decompress mode. un-squish time. 🦋
• -f, --force — force output file overwrite. she will not ask twice. 💅
• -h, --help — display this help and exit. the girlie will explain herself. 📖
• -j, --rm — remove source file(s); that's the gzip(1)-like behaviour. bye bye original. 😭
• -k, --keep — keep source file(s); that's the zstd(1)-like behaviour. original stays, we protect her. 🫶
• -n, --no-copy-stat — do not copy source file(s) attributes. fresh file, no inherited lore. ✨
• -o FILE, --output=FILE — output file; valid only if there is a single input entry. one input, one output. don't be greedy. 🙅
• -q NUM, --quality=NUM — compression level (0-11); bigger values cause denser, but slower compression. yes this goes higher than -#. she contains multitudes. 🔥
• -t, --test — test file integrity mode. just checking, not committing. 👀
• -v, --verbose — increase output verbosity. she starts telling you everything. 🗣️
• -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. bigger window = denser output but the decoder's gotta have the RAM for it. plan accordingly bestie. 🧠
• -C B64, --comment=B64 — set comment; argument is base64-decoded first; when decoding: check stream comment; when encoding: embed comment (fingerprint). a lil signature, a lil mark of ownership. 💌
• -D FILE, --dictionary=FILE — use FILE as raw (LZ77) dictionary; same dictionary MUST be used both for compression and decompression. like, this is not a suggestion. both sides or it breaks. ⚠️
• -K, --concatenated — when decoding, allow concatenated brotli streams as input. multiple streams walking in together, holding hands. 🌈
• -S SUF, --suffix=SUF — output file suffix (default: .br). pick your own lil ending. 🎀
• -V, --version — display version and exit. she'll tell you what era she's in. ⭐
• -Z, --best — use best compression level (default); same as -q 11. maximum effort, maximum density, maximum icon behaviour. 👑

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🌈 SEE ALSO 🌈

the brotli file format is defined in RFC 7932 (https://www.ietf.org/rfc/rfc7932.txt). the receipts, the lore, the whole spec.

brotli is open-sourced under the MIT License (https://opensource.org/licenses/MIT). free to use, free to love. 🫶

Mailing list: https://groups.google.com/forum/#!forum/brotli — come hang out, iykyk. 💜

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💀 BUGS 💀

found something cursed? report bugs at: https://github.com/google/brotli/issues

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and that's the whole page bestie, you're officially brotli-pilled. this was brotli version 1.0.9, dated August 14 2021, and honestly? she's been slaying since day one. go compress something. 💖✨🎀