Moved PNG loading to common.

common/image.go

@@ -8,6 +8,7 @@ import (
 	"bufio"
 	"image"
 	"image/png"
+	"log"
 	"os"
 )
 
@@ -22,3 +23,20 @@ func SaveAsPNG(path string, img image.Image) (err error) {
 	file.Close()
 	return
 }
+
+func LoadPNG(path string) image.Image {
+	var err error
+	var file *os.File
+	if file, err = os.Open(path); err != nil {
+		//log.Printf("WARN: %s", err)
+		return image.White
+	}
+	defer file.Close()
+	reader := bufio.NewReader(file)
+	var img image.Image
+	if img, err = png.Decode(reader); err != nil {
+		log.Printf("WARN: %s", err)
+		return image.White
+	}
+	return img
+}