Documentation
¶
Overview ¶
Package png implements a PNG image decoder and encoder.
The PNG specification is at https://www.w3.org/TR/PNG/.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Decode ¶
Decode reads a PNG image from r and returns it as an image.Image. The type of Image returned depends on the PNG contents.
func DecodeConfig ¶
DecodeConfig returns the color model and dimensions of a PNG image without decoding the entire image.
Types ¶
type CompressionLevel ¶ added in go1.4
type CompressionLevel int
CompressionLevel indicates the compression level.
const ( DefaultCompression CompressionLevel = 0 NoCompression CompressionLevel = -1 BestSpeed CompressionLevel = -2 BestCompression CompressionLevel = -3 )
type Encoder ¶ added in go1.4
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.
type EncoderBuffer ¶ added in go1.9
type EncoderBuffer encoder
EncoderBuffer holds the buffers used for encoding PNG images.
type EncoderBufferPool ¶ added in go1.9
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 (FormatError) Error ¶
func (e FormatError) Error() string
type UnsupportedError ¶
type UnsupportedError string
An UnsupportedError reports that the input uses a valid but unimplemented PNG feature.
func (UnsupportedError) Error ¶
func (e UnsupportedError) Error() string
Source Files