Osprey 240e/450e User Guide

Preview Pin to VMR9

Figure 66. Video Mixing Renderer 9

Video Mixing Renderer 9 is the newest video rendering method and the one on which Microsoft supposedly is basing its future development. The intent is to combine the functionality of the Overlay Mixer plus Video Renderer in one module that takes advantage of the latest developments in DirectShow. We are finding that at its present stage of development, with our hardware, VMR9 does not achieve the high efficiency of YUY2–to–VMR7. Also, although VMR9 is supposed to function as an overlay mixer for rendering captioning from the driver’s DShow CC or VBI pin, we have never seen it function correctly.

Some Data Points

The following measurements are CPU percent on two machines – a fairly old P4, and a dual Opteron

244. The video size is 640 x 480. The screen depth is 32 bits. The following abbreviations are used:

YUY2

the Osprey driver’s preview pin in YUY2 format

 

 

RGB15

the Osprey driver’s preview pin in RGB15 format

 

 

RGB32

the Osprey driver’s preview pin in RGB32 format

 

 

VR

old Video Renderer

 

 

VMR7

Video Mixing Renderer 7

 

 

VMR9

Video Mixing Renderer 9

 

 

AVI

AVI Decompressor

 

 

OVL

Overlay Mixer

 

 

The PostProc results are shown in two modes: with all post processing filters turned off, and with the adaptive deinterlace filter turned on.

Generally these results show the following:

The desirability of newer machines for video processing has to do with system architecture more than raw CPU speed.

VMR7 is generally fastest. If you don’t need the driver’s PostProcessing, then Direct Mode with VMR7 is especially fast.

Results for specific pathways can be inconsistent across different machines. For example, on the P4, YUV to VR is faster than RGB to VR; on the Opteron, RGB is faster.

In evaluating these benchmarks, remember that all of them involve video rendering to the screen. Depending on the exact pathway, video rendering can result in CPU utilization that is a lot higher than for other capture scenarios. If you are streaming video or capturing to file, you do not see numbers this high. If you are encoding video, you may see high CPU utilization, but much or most of it is from the encoder rather than the driver.

ViewCast

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ViewCast 450E, 240E manual Preview Pin to VMR9, Some Data Points