Fix review

options.go

@@ -5,27 +5,25 @@ package bimg
 #include "vips/vips.h"
 */
 import "C"
-import "fmt"
+import "errors"
 
 const (
 	// Quality defines the default JPEG quality to be used.
 	Quality = 75
-	// maxSize defines the maximum pixels width or height supported.
 )
 
+// maxSize defines maximum pixels width or height supported.
 var maxSize = 16383
 
 // MaxSize returns maxSize.
-// maxSize defines maximum pixels width or height supported.
 func MaxSize() int {
 	return maxSize
 }
 
 // SetMaxSize sets maxSize.
-// maxSize defines maximum pixels width or height supported.
 func SetMaxsize(s int) error {
 	if s <= 0 {
-		return fmt.Errorf("invalid size.A size must be 0.")
+		return errors.New("Size must be higher than zero.")
 	}
 
 	maxSize = s

vips.go

@@ -564,7 +564,7 @@ func vipsExtract(image *C.VipsImage, left, top, width, height int) (*C.VipsImage
 	var buf *C.VipsImage
 	defer C.g_object_unref(C.gpointer(image))
 
-	if width > MaxSize() || height > MaxSize() {
+	if width > maxSize || height > maxSize {
 		return nil, errors.New("Maximum image size exceeded")
 	}
 
@@ -581,7 +581,7 @@ func vipsSmartCrop(image *C.VipsImage, width, height int) (*C.VipsImage, error)
 	var buf *C.VipsImage
 	defer C.g_object_unref(C.gpointer(image))
 
-	if width > MaxSize() || height > MaxSize() {
+	if width > maxSize || height > maxSize {
 		return nil, errors.New("Maximum image size exceeded")
 	}