[Go] Convert JPEG

convert_jpeg.go

func ConvertToJpeg(src io.Reader, dst io.Writer, quality int) error {
	img, _, err := image.Decode(src)
	if err != nil {
		return err
	}

	opts := &jpeg.Options{Quality: quality}
	err = jpeg.Encode(dst, img, opts)
	if err != nil {
		return err
	}
	return nil
}

sample.go

func sample(srcImage io.Reader) {
	pr, pw := io.Pipe()
	errChan := make(chan error, 1)
	go func() {
		defer pw.Close()
		err := lib.ConvertToJpeg(srcImage, pw, 90)
		errChan <- err
	}()
  
	err := <- errChan
  
	// use pw
}