# MPEG-4 video object type ## Overview - Containing profile atom: Track (video), movie - `part-ID`: `0x20202020` (universal feature) - `feature-code`: `'m4vo'` - `feature-value`: Unsigned `int(32)` where the least significant 8 bits hold the `video_object_type_indication` found in the `VideoObjectLayer` (Described in ISO/IEC 14496-2, subclause 6.2.3). The `VideoObjectLayer` is found in the MPEG-4 Elementary Stream Descriptor Atom within the `'esds'` sample description atom of the video sample description for the QuickTime video codec of type `'mp4v'`. ## Feature Values The value is a video object type constant that indicates a set of video tools. The list of video object type constants is defined in specification ISO/IEC 14496-2, subclause 6.3.3. The least significant 8 bits hold the value. The most significant 24 bits should be set to `0`. Example: The Simple Object Type video object is indicated by the value `1`. ## Writer Responsibilities A writer of the MPEG-4 Video Object Type feature should record the 8 bits corresponding to the `video_object_type_indication` found in the `VideoObjectLayer` within the `ES_descriptor`’s video `DecoderSpecificConfig`. The most significant 24 bits of the value should be set to `0`. This feature should be written only for MPEG-4 video of video object type `1` (Video ID). If the MPEG-4 video does not use Video ID (`1`) for `visual_object_type`, the esds will have no `VideoObjectLayer` and consequently no `video_object_type_indication`. In this case, no MPEG-4 Video Object Type feature should be written. > Note: A writer that records the MPEG-4 Video Object Type feature for encoded video using the Video ID visual object type is encouraged to write the MPEG-4 Video Codec and MPEG-4 Video Profile features as well. ## Feature Value Algorithm The MPEG-4 video object type is the least significant 8 bits of the `video_object_type_indication` found in the `VideoObjectLayer`. See ISO/IEC 14496-2, subclause 6.2.3. The `VideoObjectLayer` is found in the MPEG-4 Elementary Stream Descriptor Atom within the `'esds'` sample description atom of the video sample description for the QuickTime video codec of type `'mp4v'`. ## Reader Responsibilities A reader of this feature code should compare the recorded value with the set of MPEG-4 video tools supported by the reader. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)