/
main.go
58 lines (51 loc) · 866 Bytes
/
main.go
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package main
import (
"fmt"
"image"
"image/jpeg"
"image/png"
"os"
"path"
"strings"
)
func main() {
args := os.Args
if len(args) <= 1 {
fmt.Println("no files")
return
}
filenames := args[1:]
for _, filename := range filenames {
err := convert(filename)
if err != nil {
fmt.Println(err)
} else {
fmt.Println(filename)
}
}
}
func read(filename string) (image.Image, error) {
file, err := os.Open(filename)
if err != nil {
return nil, err
}
return jpeg.Decode(file)
}
func convert(filename string) error {
ext := path.Ext(filename)
pngFilename := strings.TrimSuffix(filename, ext) + ".png"
jpeg, err := read(filename)
if err != nil {
return err
}
file, err := os.Create(pngFilename)
if err != nil {
return err
}
err = png.Encode(file, jpeg)
if err != nil {
os.Remove(pngFilename)
return err
}
return nil
}