Golang : Crop image

This is a continuation from the previous tutorial on how to resize image in Golang. For this tutorial, we will learn how easy it is to crop image with the excellent https://github.com/disintegration/imaging package.

This code below will create two images. One which is cropped from center point and another cropped according to the defined rectangular region.

 package main

 import (
 "fmt"
 "github.com/disintegration/imaging"
 "os"
 "runtime"
 "image"
 )

 func main() {

 // maximize CPU usage for maximum performance
 runtime.GOMAXPROCS(runtime.NumCPU())

 // load original image
 img, err := imaging.Open("./big.jpg")

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 // crop from center
 centercropimg := imaging.CropCenter(img, 300, 300)

 // save cropped image
 err = imaging.Save(centercropimg, "./centercrop.jpg")

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 // crop out a rectangular region
 rectcropimg := imaging.Crop(img, image.Rect(0, 0, 500, 500))

 // save cropped image
 err = imaging.Save(rectcropimg, "./rectcrop.jpg")

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 // everything ok
 fmt.Println("Done")

 }

Big.jpg(original)

Centercrop.jpg

Rectcrop.jpg

For more information and other functions to manipulate images, please see http://godoc.org/github.com/disintegration/imaging