前段时间想做个图片站，就用手机照了很多相片，但是要一个个用PS去压缩修改尺寸太麻烦了。最后想到了用golang去实现，算是边学边练吧。其中用到了github测试数据/nfnt/resize这个第三方库，仅仅支持JPG图片格式。
复制代码 代码如下:
package main
import (
??? "fmt"
??? "github测试数据/nfnt/resize"
??? "image"
??? "image/draw"
??? "image/jpeg"
??? "image/png"
??? "io/ioutil"
??? "log"
??? "math/rand"
??? "os"
??? "runtime"
??? "strconv"
??? "strings"
??? "time"
)
func main() {
??? runtime.GOMAXPROCS(runtime.NumCPU())
??? cmd("data/")
??? fmt.Println("OK!")
}
// 执行操作
func cmd(path string) {
??? files, _ := ioutil.ReadDir(path)
??? for _, file := range files {
??????? if file.IsDir() {
??????????? fmt.Println("目录" + file.Name())
??????????? cmd(path + file.Name() + "/")
??????? } else {
??????????? if strings.Contains(strings.ToLower(file.Name()), ".jpg") {
??????????????? // 随机名称
??????????????? to := path + random_name() + ".jpg"
??????????????? origin := path + file.Name()
??????????????? fmt.Println("正在处理" + origin + ">>>" + to)
??????????????? cmd_resize(origin, 2048, 0, to)
??????????????? defer os.Remove(origin)
??????????? }
??????? }
??? }
}
// 改变大小
func cmd_resize(file string, width uint, height uint, to string) {
??? // 打开图片并解码
??? file_origin, _ := os.Open(file)
??? origin, _ := jpeg.Decode(file_origin)
??? defer file_origin.Close()
??? canvas := resize.Resize(width, height, origin, resize.Lanczos3)
??? file_out, err := os.Create(to)
??? if err != nil {
??????? log.Fatal(err)
??? }
??? defer file_out.Close()
??? jpeg.Encode(file_out, canvas, &jpeg.Options{80})
??? // cmd_watermark(to, strings.Replace(to, ".jpg", "@big.jpg", 1))
??? cmd_thumbnail(to, 480, 360, strings.Replace(to, ".jpg", "@small.jpg", 1))
}
func cmd_thumbnail(file string, width uint, height uint, to string) {
??? // 打开图片并解码
??? file_origin, _ := os.Open(file)
??? origin, _ := jpeg.Decode(file_origin)
??? defer file_origin.Close()
??? canvas := resize.Thumbnail(width, height, origin, resize.Lanczos3)
??? file_out, err := os.Create(to)
??? if err != nil {
??????? log.Fatal(err)
??? }
??? defer file_out.Close()
??? jpeg.Encode(file_out, canvas, &jpeg.Options{80})
}
// 水印
func cmd_watermark(file string, to string) {
??? // 打开图片并解码
??? file_origin, _ := os.Open(file)
??? origin, _ := jpeg.Decode(file_origin)
??? defer file_origin.Close()
??? // 打开水印图并解码
??? file_watermark, _ := os.Open("watermark.png")
??? watermark, _ := png.Decode(file_watermark)
??? defer file_watermark.Close()
??? //原始图界限
??? origin_size := origin.Bounds()
??? //创建新图层
??? canvas := image.NewNRGBA(origin_size)
??? // 贴原始图
??? draw.Draw(canvas, origin_size, origin, image.ZP, draw.Src)
??? // 贴水印图
??? draw.Draw(canvas, watermark.Bounds().Add(image.Pt(30, 30)), watermark, image.ZP, draw.Over)
??? //生成新图片
??? create_image, _ := os.Create(to)
??? jpeg.Encode(create_image, canvas, &jpeg.Options{95})
??? defer create_image.Close()
}
// 随机生成文件名
func random_name() string {
??? rand.Seed(time.Now().UnixNano())
??? return strconv.Itoa(rand.Int())
}
以上就是本文所述的全部内容了，希望能够对大家熟练掌握go语言有所帮助。