From fd9f924ad730f94f9022ee4b7391c0e99a14a272 Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Fri, 4 Jul 2014 18:03:48 -0700
Subject: [PATCH] add a convenient function to preprocess images on client
 side.

---
 go/images/preprocess.go | 25 +++++++++++++++++++++++++
 go/images/resizing.go   |  2 +-
 2 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 go/images/preprocess.go

diff --git a/go/images/preprocess.go b/go/images/preprocess.go
new file mode 100644
index 000000000..b5907b1b8
--- /dev/null
+++ b/go/images/preprocess.go
@@ -0,0 +1,25 @@
+package images
+
+import (
+	"path/filepath"
+)
+
+/*
+* Preprocess image files on client side.
+* 1. possibly adjust the orientation
+* 2. resize the image to a width or height limit
+* 3. remove the exif data
+* Call this function on any file uploaded to weedfs
+* 
+*/
+func MaybePreprocessImage(filename string, data []byte, width, height int) (resized []byte) {
+	ext := filepath.Ext(filename)
+	switch ext {
+	case ".png", ".gif":
+		return Resized(ext, data, width, height)
+	case ".jpg", ".jpeg":
+	  data = FixJpgOrientation(data)
+		return Resized(ext, data, width, height)
+	}
+	return data
+}
diff --git a/go/images/resizing.go b/go/images/resizing.go
index f5077c1fd..6e774e1db 100644
--- a/go/images/resizing.go
+++ b/go/images/resizing.go
@@ -25,7 +25,7 @@ func Resized(ext string, data []byte, width, height int) (resized []byte) {
 		switch ext {
 		case ".png":
 			png.Encode(&buf, dstImage)
-		case ".jpg":
+		case ".jpg", ".jpeg":
 			jpeg.Encode(&buf, dstImage, nil)
 		case ".gif":
 			gif.Encode(&buf, dstImage, nil)