Package: github.com/klauspost/compress/flate

package flate Import Path github.com/klauspost/compress/flate (on go.dev) Dependency Relation imports 11 packages, and imported by 3 packages

Involved Source Files deflate.go dict_decoder.go fast_encoder.go huffman_bit_writer.go huffman_code.go huffman_sortByFreq.go huffman_sortByLiteral.go d inflate.go Package flate implements the DEFLATE compressed data format, described in RFC 1951. The gzip and zlib packages implement access to DEFLATE-based file formats. inflate_gen.go level1.go level2.go level3.go level4.go level5.go level6.go matchlen_amd64.go regmask_amd64.go stateless.go token.go matchlen_amd64.s

Package-Level Functions (total 7)

func NewReader(r io.Reader) io.ReadCloser NewReader returns a new ReadCloser that can be used to read the uncompressed version of r. If r does not also implement io.ByteReader, the decompressor may read more data than necessary from r. It is the caller's responsibility to call Close on the ReadCloser when finished reading. The ReadCloser returned by NewReader also implements Resetter.

func NewReaderDict(r io.Reader, dict []byte) io.ReadCloser NewReaderDict is like NewReader but initializes the reader with a preset dictionary. The returned Reader behaves as if the uncompressed data stream started with the given dictionary, which has already been read. NewReaderDict is typically used to read data compressed by NewWriterDict. The ReadCloser returned by NewReader also implements Resetter.

func NewStatelessWriter(dst io.Writer) io.WriteCloser NewStatelessWriter will do compression but without maintaining any state between Write calls. There will be no memory kept between Write calls, but compression and speed will be suboptimal. Because of this, the size of actual Write calls will affect output size.

func NewWriter(w io.Writer, level int) (*Writer, error) NewWriter returns a new Writer compressing data at the given level. Following zlib, levels range from 1 (BestSpeed) to 9 (BestCompression); higher levels typically run slower but compress more. Level 0 (NoCompression) does not attempt any compression; it only adds the necessary DEFLATE framing. Level -1 (DefaultCompression) uses the default compression level. Level -2 (ConstantCompression) will use Huffman compression only, giving a very fast compression for all types of input, but sacrificing considerable compression efficiency. If level is in the range [-2, 9] then the error returned will be nil. Otherwise the error returned will be non-nil.

func NewWriterDict(w io.Writer, level int, dict []byte) (*Writer, error) NewWriterDict is like NewWriter but initializes the new Writer with a preset dictionary. The returned Writer behaves as if the dictionary had been written to it without producing any compressed output. The compressed data written to w can only be decompressed by a Reader initialized with the same dictionary.

func NewWriterWindow(w io.Writer, windowSize int) (*Writer, error) NewWriterWindow returns a new Writer compressing data with a custom window size. windowSize must be from MinCustomWindowSize to MaxCustomWindowSize.

func StatelessDeflate(out io.Writer, in []byte, eof bool, dict []byte) error StatelessDeflate allows compressing directly to a Writer without retaining state. When returning everything will be flushed. Up to 8KB of an optional dictionary can be given which is presumed to precede the block. Longer dictionaries will be truncated and will still produce valid output. Sending nil dictionary is perfectly fine.

Package-Level Constants (total 8)

const BestCompression = 9

const BestSpeed = 1

const ConstantCompression = -2 // compatibility alias.

const DefaultCompression = -1

const HuffmanOnly = -2 HuffmanOnly disables Lempel-Ziv match searching and only performs Huffman entropy encoding. This mode is useful in compressing data that has already been compressed with an LZ style algorithm (e.g. Snappy or LZ4) that lacks an entropy encoder. Compression gains are achieved when certain bytes in the input stream occur more frequently than others. Note that HuffmanOnly produces a compressed output that is RFC 1951 compliant. That is, any valid DEFLATE decompressor will continue to be able to decompress this output.

const MaxCustomWindowSize = 32768 MaxCustomWindowSize is the maximum custom window that can be sent to NewWriterWindow.

const MinCustomWindowSize = 32 MinCustomWindowSize is the minimum window size that can be sent to NewWriterWindow.

const NoCompression = 0