tiff - ActiveState ActiveGo 1.8

Package tiff

import "golang.org/x/image/tiff"

Overview ▾

Package tiff implements a TIFF image decoder and encoder.

The TIFF specification is at http://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf

func Decode

func Decode(r io.Reader) (img image.Image, err error)

Decode reads a TIFF image from r and returns it as an image.Image. The type of Image returned depends on the contents of the TIFF.

func DecodeConfig

func DecodeConfig(r io.Reader) (image.Config, error)

DecodeConfig returns the color model and dimensions of a TIFF image without decoding the entire image.

func Encode

func Encode(w io.Writer, m image.Image, opt *Options) error

Encode writes the image m to w. opt determines the options used for encoding, such as the compression type. If opt is nil, an uncompressed image is written.

type CompressionType

CompressionType describes the type of compression used in Options.

type CompressionType int
const (
    Uncompressed CompressionType = iota

type FormatError

A FormatError reports that the input is not a valid TIFF image.

type FormatError string

func (FormatError) Error

func (e FormatError) Error() string

type Options

Options are the encoding parameters.

type Options struct {
    // Compression is the type of compression used.
    Compression CompressionType
    // Predictor determines whether a differencing predictor is used;
    // if true, instead of each pixel's color, the color difference to the
    // preceding one is saved.  This improves the compression for certain
    // types of images and compressors. For example, it works well for
    // photos with Deflate compression.
    Predictor bool

type UnsupportedError

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

type UnsupportedError string

func (UnsupportedError) Error

func (e UnsupportedError) Error() string


Name Synopsis
lzw Package lzw implements the Lempel-Ziv-Welch compressed data format, described in T. A. Welch, ``A Technique for High-Performance Data Compression'', Computer, 17(6) (June 1984), pp 8-19.