Go PNG Decoder
Many file formats are stored and transferred as one-dimensional sequences of bytes. The purpose of a decoder is to transform this stream into a data structure that can be manipulated by a program.
A key component of the
image/png
package in the Go
standard library is the
decoder
struct, an aggregate data
type that collates a PNG data stream into an
object that fulfills the
image.Image
interface.
image.Image
provides the color
model, dimensions, and pixel coordinates of an
image file. A Go program can use this data to
transform a PNG prior to encoding it back into a
byte stream.
type decoder struct {
r io.Reader
img image.Image
crc hash.Hash32
width, height int
depth int
palette color.Palette
cb int
stage int
idatLength uint32
tmp [3 * 256]byte
interlace int
useTransparent bool
transparent [6]byte
}