Missing changes

thumb_image.go

@@ -7,12 +7,22 @@ import (
 	"image/jpeg"
 	_ "image/png"
 	"io"
+	"path/filepath"
+	"strings"
 )
 
 func init() {
 	thumbnailers = append(thumbnailers, &imageThumbnailer{})
 }
 
+// isImageFile reports whether name is a raster image we can thumbnail and thus
+// embed on a page. Video files also carry thumbnails but are not embeddable, so
+// this keys on the image thumbnailer's own extension set rather than
+// hasThumbnail.
+func isImageFile(name string) bool {
+	return (&imageThumbnailer{}).CanHandle(strings.ToLower(filepath.Ext(name)))
+}
+
 type imageThumbnailer struct{}
 
 func (it *imageThumbnailer) CanHandle(ext string) bool {