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Brotli Compress and Decompress: In-Browser Wasm
Compress one file to a .br brotli stream or decode one back: quality 0-11, both sides capped before the wasm runs, no container metadata claimed.
Brotli has no magic signature: a truncated or non-brotli file is rejected by the decoder itself, and the message says exactly that. One stream per file: names and containers are gzip/zip territory, not brotli's.
Higher quality compresses smaller and runs slower (11 is glacial on large files). The wasm encoder runs in the archive worker; the page never blocks on it.