| Microsoft DirectX 8.1 (C++) |
The IQualProp interface provides methods for retrieving performance information from video renderers. The values returned through the interface are reset each time the filter is stopped. The Video Renderer filter and the Full Screen Renderer filter expose this interface.
Applications can use this interface to retrieve video performance information.
In addition to the methods inherited from IUnknown, the IQualProp interface exposes the following methods.
| Method | Description |
| get_AvgFrameRate | Retrieves the average frame rate achieved. |
| get_AvgSyncOffset | Retrieves the average time difference between when a frame was due for rendering and when rendering actually began (this is returned as a value in milliseconds). |
| get_DevSyncOffset | Retrieves the average time difference between when a frame was due for rendering and when rendering actually began (this is returned as a standard deviation). |
| get_FramesDrawn | Retrieves the number of frames drawn since streaming started. |
| get_FramesDroppedInRenderer | Retrieves the number of frames dropped by the renderer. |
| get_Jitter | Expresses the average time between successive frames delivered to the video renderer. |