Function WithWindowSize

zstd/encoder_options.go:111–133

WithWindowSize will set the maximum allowed back-reference distance. The value must be a power of two between MinWindowSize and MaxWindowSize. A larger value will enable better compression but allocate more memory and, for above-default values, take considerably longer. The default value is determin

(n int)

// The default value is determined by the compression level and max 8MB.
// Cannot be changed with ResetWithOptions.
func WithWindowSize(n int) EOption {
	return func(o *encoderOptions) error {
		switch {
		case n < MinWindowSize:
			return fmt.Errorf("window size must be at least %d", MinWindowSize)
		case n > MaxWindowSize:
			return fmt.Errorf("window size must be at most %d", MaxWindowSize)
		case (n & (n - 1)) != 0:
			return errors.New("window size must be a power of 2")
		}
		if o.resetOpt && n != o.windowSize {
			return errors.New("WithWindowSize cannot be changed on Reset")
		}

		o.windowSize = n
		o.customWindow = true
		if o.blockSize > o.windowSize {
			o.blockSize = o.windowSize
			o.customBlockSize = true
		}
		return nil
	}
}

// WithEncoderPadding will add padding to all output so the size will be a multiple of n.
// This can be used to obfuscate the exact output size or make blocks of a certain size.