How to covert a []byte object to an image and store it as a jpeg image on disk

Question

I am trying to convert an []byte object to an image and save it as a jpeg in Golang. I tried to use Decode function of image but it always returns <nil>.

func saveFrames(imgByte []byte) {
    img, _, _ := image.Decode(bytes.NewReader(imgByte))
   out, err := os.Create("./img.jpeg")

   if err != nil {
             fmt.Println(err)
             os.Exit(1)
   }
   err = jpeg.Encode(out, img)
   if err != nil {
            fmt.Println(err)
            os.Exit(1)
   }
}

Possible duplicate of [How to read/write from/to file using Go?](https://stackoverflow.com/questions/1821811/how-to-read-write-from-to-file-using-go) — Oliver Baumann, Oct 23 '18 at 10:50

score 8 · Accepted Answer · answered Oct 23 '18 at 11:27

8

You are not passing Options,to jpeg.Encode, you can also set it to nil.

func serveFrames(imgByte []byte) {

    img, _, err := image.Decode(bytes.NewReader(imgByte))
    if err != nil {
        log.Fatalln(err)
    }

    out, _ := os.Create("./img.jpeg")
    defer out.Close()

    var opts jpeg.Options
    opts.Quality = 1

    err = jpeg.Encode(out, img, &opts)
    //jpeg.Encode(out, img, nil)
    if err != nil {
        log.Println(err)
    }

}

Don't forget to close any file, if opened.

You can use log.Fatalln(...), if you want to print error message and quit in-case of any error.

answered Oct 23 '18 at 11:27

nilsocket

1,441
9
17

2018/10/23 14:03:42 invalid JPEG format: short Huffman data Getting this error: – shahidammer Oct 23 '18 at 12:03
@shahidammer, data in `imgByte` should data of some image – nilsocket Oct 23 '18 at 12:08
Quality 1? Even 100 looks terrible. Isn't there a better way which doesn't play with quality? Or does it depend on bytes? – Shivang Kakkar Feb 21 '22 at 13:03

score 0 · Answer 2 · answered Mar 11 '23 at 03:12

0

guess this is what u really want:

err = ioutil.WriteFile(path, bt, 0644)

answered Mar 11 '23 at 03:12

zenopein

1

How to covert a []byte object to an image and store it as a jpeg image on disk

2 Answers2