Encoding after decoding failed: unsupported image type

[bayandin]

Here is another issue I found with the help of go-fuzz:
I'm able to decode data but aren't able to encode it back.

package main

import (
	"bytes"
	"fmt"

	"github.com/pixiv/go-libjpeg/jpeg"
)

func main() {
	data := []byte("\xff\xd8\xff\xdb\x00C\x000000000000000" +
		"00000000000000000000" +
		"00000000000000000000" +
		"00000000000\xff\xc0\x00\x11\b\x00000" +
		"\x03R\"\x00G\x11\x00B\x11\x00\xff\xda\x00\f\x03R\x00G\x00B" +
		"\x00")

	img, err := jpeg.Decode(bytes.NewReader(data), &jpeg.DecoderOptions{})
	if err != nil {
		return
	}

	var w bytes.Buffer
	err = jpeg.Encode(&w, img, &jpeg.EncoderOptions{})
	if err != nil {
		panic(err)
	}
}

It prints

Invalid SOS parameters for sequential JPEG
panic: unsupported image type

I use go version go1.12.9 darwin/amd64, libjpeg-turbo 2.0.2

[harukasan]

👍
I fixed in #57.