resize

Documentation

Index

• func Resize(width, height uint, img image.Image, interp InterpolationFunction) image.Image
• func Thumbnail(maxWidth, maxHeight uint, img image.Image, interp InterpolationFunction) image.Image
• type InterpolationFunction

Functions

func Resize

func Resize(width, height uint, img image.Image, interp InterpolationFunction) image.Image

Resize scales an image to new width and height using the interpolation function interp. A new image with the given dimensions will be returned. If one of the parameters width or height is set to 0, its size will be calculated so that the aspect ratio is that of the originating image. The resizing algorithm uses channels for parallel computation. If the input image has width or height of 0, it is returned unchanged.

func Thumbnail

func Thumbnail(maxWidth, maxHeight uint, img image.Image, interp InterpolationFunction) image.Image

Thumbnail will downscale provided image to max width and height preserving original aspect ratio and using the interpolation function interp. It will return original image, without processing it, if original sizes are already smaller than provided constraints.

Types

type InterpolationFunction

type InterpolationFunction int

An InterpolationFunction provides the parameters that describe an interpolation kernel. It returns the number of samples to take and the kernel function to use for sampling.

const (
	// Nearest-neighbor interpolation
	NearestNeighbor InterpolationFunction = iota
	// Bilinear interpolation
	Bilinear
	// Bicubic interpolation (with cubic hermite spline)
	Bicubic
	// Mitchell-Netravali interpolation
	MitchellNetravali
	// Lanczos interpolation (a=2)
	Lanczos2
	// Lanczos interpolation (a=3)
	Lanczos3
)

InterpolationFunction constants