1960746 - (wmf-h264) Some H264 videos are not supported on Window Media Foundation Decoder

Status: NEW

(Web Compatibility :: Knowledge Base, defect)

Description

[Alastor Wu [:alwu]]

On Windows, according to the Microsoft's documentation, the following are the supported H.264 formats

Setting	Format
Profiles/Levels	Baseline, Main, and High profiles, up to level 5.1. (See ITU-T H.264 specification for details.) [1]
Chroma Formats	4:2:0 chroma or monochrome
Minimum Resolution	48 × 48 pixels
Maximum Resolution	4096 × 2304 pixels <br><br>The maximum guaranteed resolution for DXVA acceleration is 1920 × 1088 pixels; at higher resolutions, decoding is done with DXVA if supported by hardware, otherwise, decoding is done with software. <br>Note: In Windows 7, the maximum supported resolution is 1920 × 1088 pixels for both software and DXVA decoding.
DXVA	The decoder supports DXVA version 2, but not DXVA version 1. DXVA decoding is supported only for Main-compatible Baseline, Main, and High profile bitstreams. (Main-compatible Baseline bitstreams are defined as profile_idc=66 and constrained_set1_flag=1.)

We have encountered several issues, such as bug 1908296 and bug 1931436, which are caused by formats not supported by the Windows Media Foundation H.264 decoder.

[1] The decoder actually supports up to 6.2.