Allow use of native image/jpeg

README.md

@@ -12,7 +12,7 @@ or
 ### Requirements
 
 * [OpenCV](http://opencv.org/) (default is version 2.x via [go-opencv](https://github.com/lazywei/go-opencv), use `-tags cv3` for [gocv](https://github.com/hybridgroup/gocv))
-* [libjpeg-turbo](https://www.libjpeg-turbo.org/)
+* [libjpeg-turbo](https://www.libjpeg-turbo.org/) (use `-tags jpeg` for native image/jpeg)
 
 
 ### Download

encoder/encode.go

@@ -1,9 +1,10 @@
+// +build !jpeg
+
 // Package encoder.
 package encoder
 
 import (
 	"image"
-	//"image/jpeg"
 	"io"
 
 	jpeg "github.com/antonini/golibjpegturbo"

encoder/encode_jpeg.go

@@ -0,0 +1,30 @@
+// +build jpeg
+
+// Package encoder.
+package encoder
+
+import (
+	"image"
+	"image/jpeg"
+	"io"
+)
+
+// New returns a new Encoder.
+func New(w io.Writer) *Encoder {
+	return &Encoder{w}
+}
+
+// Encoder struct.
+type Encoder struct {
+	w io.Writer
+}
+
+// Encode encodes image to JPEG.
+func (e Encoder) Encode(img image.Image) error {
+	err := jpeg.Encode(e.w, img, &jpeg.Options{Quality: 75})
+	if err != nil {
+		return err
+	}
+
+	return nil
+}