diff --git a/pepic/utils/file.go b/pepic/utils/file.go
index 90a5f02..498b137 100644
--- a/pepic/utils/file.go
+++ b/pepic/utils/file.go
@@ -15,6 +15,7 @@ var canonicalExtensions = map[string]string{
 	".jpeg": ".jpg",
 	".jfif": ".jpg",
 	".qt":   ".mov",
+	".f4v":  ".mp4",
 }
 
 func ExtensionByMimeType(mimeType string) (string, error) {