From bfcc7c72ace85464b957ff76c3d8deddd26b8d72 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?David=20Ho=CC=88gborg?= <david.hogborg@greatbeyond.se>
Date: Fri, 17 Jul 2015 12:48:13 +0200
Subject: [PATCH] write output as jpeg as option

---
 gopow.go                |  2 +-
 internal/gopow/gopow.go | 18 +++++++++++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/gopow.go b/gopow.go
index 45e9da7..a14111d 100644
--- a/gopow.go
+++ b/gopow.go
@@ -66,7 +66,7 @@ func main() {
 		cli.StringFlag{
 			Name:  "format,f",
 			Value: "png",
-			Usage: "Output file format, default png",
+			Usage: "Output file format, default png [png,jpeg]",
 		},
 		cli.BoolFlag{
 			Name:  "verbose",
diff --git a/internal/gopow/gopow.go b/internal/gopow/gopow.go
index f0dad79..e0c8fd6 100644
--- a/internal/gopow/gopow.go
+++ b/internal/gopow/gopow.go
@@ -3,6 +3,7 @@ package gopow
 import (
 	"fmt"
 	"image"
+	"image/jpeg"
 	"image/png"
 	"os"
 	"time"
@@ -108,7 +109,22 @@ func (g *GoPow) Write() error {
 		return err
 	}
 
-	err = png.Encode(out, g.image)
+	switch g.config.Format {
+	case "png":
+		err = png.Encode(out, g.image)
+		break
+
+	case "jpeg", "jpg":
+		opt := &jpeg.Options{
+			Quality: 98,
+		}
+		err = jpeg.Encode(out, g.image, opt)
+		break
+
+	default:
+		return fmt.Errorf("unsupported format: %s", g.config.Format)
+	}
+
 	if err != nil {
 		return err
 	}