golang-imagick图片去除边框（黑边，白边）

package main

import (
    "fmt"
    "github.com/gographics/imagick/imagick"
    "io/ioutil"
    "os"
    "strconv"
)

func ReadFile(path string) (string, error) {
    fi, err := os.Open(path)
    if err == nil {
        defer fi.Close()
        fd, err := ioutil.ReadAll(fi)
        return string(fd), err
    } else {
        return "", err
    }

}

func main() {

    arg_num := len(os.Args)
    if arg_num < 3 {
        fmt.Println("./tester [imagepath][trimdistance]")
        return
    }

    imagick.Initialize()
    defer imagick.Terminate()

    compMW := imagick.NewMagickWand()
    compMW.ReadImage(os.Args[1])
    trimDistance, _ := strconv.ParseFloat(os.Args[2], 0)

    err := compMW.TrimImage(trimDistance)
    if err != nil {
        fmt.Println("trim failed, ", err)
    } else {
        compMW.TrimImage(trimDistance)
        compMW.WriteImage("./trim.jpg")
        fmt.Println("trim success")
    }
    compMW.Destroy()
}