png

type CompressionLevel ¶

type CompressionLevel int

const (
	DefaultCompression CompressionLevel = 0
	NoCompression      CompressionLevel = -1
	BestSpeed          CompressionLevel = -2
	BestCompression    CompressionLevel = -3
)

type Encoder ¶

type Encoder struct {
	CompressionLevel CompressionLevel

	// BufferPool optionally specifies a buffer pool to get temporary
	// EncoderBuffers when encoding an image.
	BufferPool EncoderBufferPool
}

Encoder configures encoding PNG images.

func (enc *Encoder) Encode(w io.Writer, m image.Image) error

type EncoderBuffer ¶

type EncoderBuffer encoder

EncoderBuffer holds the buffers used for encoding PNG images.

type EncoderBufferPool ¶

type EncoderBufferPool interface {
	Get() *EncoderBuffer
	Put(*EncoderBuffer)
}

EncoderBufferPool is an interface for getting and returning temporary instances of the EncoderBuffer struct. This can be used to reuse buffers when encoding multiple images.

type FormatError ¶

type FormatError string

A FormatError reports that the input is not a valid PNG.

func (e FormatError) Error() string

type UnsupportedError ¶

type UnsupportedError string

An UnsupportedError reports that the input uses a valid but unimplemented PNG feature.

func (e UnsupportedError) Error() string