MPEG-4 Part 2 vs H.263

MPEG-4 Pt 2 has two parts, short header mode and non short header mode.

Short header mode is (baseline) H.263 compatible, with minimum set of resolutions, defined by source_format syntax, not including resolutions such as 320x240, 720x480.

Non short header mode is not H.263 compatible, and can code other resolutions beyond the minimum set of resolutions for baseline H.263.

Custom resolution support in H.263 some feature in H.263+ (H.263 v2).

 

Microsoft MPEG-4 Part 2 Video Decoder supports both short header mode (baseline H.263) and non short header mode, but not H.263+ and H.263++, up to Windows Blue.