Function EncodeBetter

s2/encode.go:117–144

EncodeBetter returns the encoded form of src. The returned slice may be a sub- slice of dst if dst was large enough to hold the entire encoded block. Otherwise, a newly allocated slice will be returned. EncodeBetter compresses better than Encode but typically with a 10-40% speed decrease on both co

(dst, src []byte)

// If you need to encode larger amounts of data, consider using
// the streaming interface which gives all of these features.
func EncodeBetter(dst, src []byte) []byte {
	if n := MaxEncodedLen(len(src)); n < 0 {
		panic(ErrTooLarge)
	} else if cap(dst) < n {
		dst = make([]byte, n)
	} else {
		dst = dst[:n]
	}

	// The block starts with the varint-encoded length of the decompressed bytes.
	d := binary.PutUvarint(dst, uint64(len(src)))

	if len(src) == 0 {
		return dst[:d]
	}
	if len(src) < minNonLiteralBlockSize {
		d += emitLiteral(dst[d:], src)
		return dst[:d]
	}
	n := encodeBlockBetter(dst[d:], src)
	if n > 0 {
		d += n
		return dst[:d]
	}
	// Not compressible
	d += emitLiteral(dst[d:], src)
	return dst[:d]
}

// EncodeBest returns the encoded form of src. The returned slice may be a sub-
// slice of dst if dst was large enough to hold the entire encoded block.