diff --git a/media/extractors/mp4/ItemTable.cpp b/media/extractors/mp4/ItemTable.cpp
index 74d5f1f..c082fc1 100644
--- a/media/extractors/mp4/ItemTable.cpp
+++ b/media/extractors/mp4/ItemTable.cpp
@@ -1058,9 +1058,12 @@
                 return ERROR_MALFORMED;
             }
 
-            String8 content_encoding;
-            if (!parseNullTerminatedString(&offset, &size, &content_encoding)) {
-                return ERROR_MALFORMED;
+            // content_encoding is optional; can be omitted if would be empty
+            if (size > 0) {
+                String8 content_encoding;
+                if (!parseNullTerminatedString(&offset, &size, &content_encoding)) {
+                    return ERROR_MALFORMED;
+                }
             }
         } else if (item_type == FOURCC('u', 'r', 'i', ' ')) {
             String8 item_uri_type;