GO语言实现批量压缩图片和水印

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.com/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.com/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。