WMV media streams look more pixelated in Windows 7 than in XP

Question

Our streaming media player is a C ++ / DirectShow home application and runs on XP and higher.

One of the most widely used streaming codecs is WMV, as it is widely supported.

We noticed that the output from WMV media streams is different from Windows 7 clients than in Windows XP.

Windows 7's output looks much more pixelated / blocky for WMV streams. The identical stream (coming from the media server) in Windows XP looks much smoother or less pixelated.

The same playback schedule is used on both platforms, and the same media server is used for encoding and stream for both clients.

The W7 client has a Windows Media codec, which is part of the Windows Media Player application.

Has anyone else noticed this problem, or can anyone comment on what I can check / fix on the Windows 7 platform?

Answer 1

From chatting with Chris P , Microsoft MVP:

The VMR9 renderer in Windows 7 doesn’t seem to support texture smoothing properties, so the whole video looks like crap. The only viable solution I found was to use EVR or a custom render. It does not implement any of these functions (but does not give any errors when it is turned on):

MixerPref9_BiLinearFiltering, 
MixerPref9_AnisotropicFiltering, 
MixerPref9_PyramidalQuadFiltering, 
MixerPref9_GaussianQuadFiltering

instead, it always seems that MixerPref9_PointFiltering is being used.

Answer 2

, , WMV . Video Renderer, Windows Vista Windows 7. , Aero . Windows 7.