Package 'Brotli'

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Package ‘brotli’ May 13, 2018 Type Package Title A Compression Format Optimized for the Web Version 1.2 Description A lossless compressed data format that uses a combination of the LZ77 algorithm and Huffman coding. Brotli is similar in speed to deflate (gzip) but offers more dense compression. License MIT + file LICENSE URL https://tools.ietf.org/html/rfc7932 (spec) https://github.com/google/brotli#readme (upstream) http://github.com/jeroen/brotli#read (devel) BugReports http://github.com/jeroen/brotli/issues VignetteBuilder knitr, R.rsp Suggests spelling, knitr, R.rsp, microbenchmark, rmarkdown, ggplot2 RoxygenNote 6.0.1 Language en-US NeedsCompilation yes Author Jeroen Ooms [aut, cre] (<https://orcid.org/0000-0002-4035-0289>), Google, Inc [aut, cph] (Brotli C++ library) Maintainer Jeroen Ooms <[email protected]> Repository CRAN Date/Publication 2018-05-13 20:31:43 UTC R topics documented: brotli . .2 Index 4 1 2 brotli brotli Brotli Compression Description Brotli is a compression algorithm optimized for the web, in particular small text documents. Usage brotli_compress(buf, quality = 11, window = 22) brotli_decompress(buf) Arguments buf raw vector with data to compress/decompress quality value between 0 and 11 window log of window size Details Brotli decompression is at least as fast as for gzip while significantly improving the compression ratio. The price we pay is that compression is much slower than gzip. Brotli is therefore most effective for serving static content such as fonts and html pages. For binary (non-text) data, the compression ratio of Brotli usually does not beat bz2 or xz (lzma), however decompression for these algorithms is too slow for browsers in e.g. mobile devices. References J. Alakuijala and Z. Szabadka (July 2016). Brotli Compressed Data Format. IETF Internet Draft https://tools.ietf.org/html/rfc7932. See Also memCompress Examples # Simple example myfile <- file.path(R.home(), "COPYING") x <- readBin(myfile, raw(), file.info(myfile)$size) y <- brotli_compress(x) stopifnot(identical(x, brotli_decompress(y))) # Compare to other algorithms length(x) length(brotli_compress(x)) length(memCompress(x, "gzip")) brotli 3 length(memCompress(x, "bzip2")) length(memCompress(x, "xz")) Index brotli,2 brotli_compress (brotli),2 brotli_decompress (brotli),2 memCompress, 2 4.

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