IQualProp::get_DevSyncOffset method (amvideo.h)
[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The get_DevSyncOffset method retrieves the average time difference between when the video frames should have been displayed and when they actually were. This method is the same as the IQualProp::get_AvgSyncOffset method except that the value returned is calculated as a standard deviation rather than as a simple average.
Syntax
HRESULT get_DevSyncOffset(
int *piDev
);
Parameters
piDev
Pointer to a value denoting the accuracy of the video frames displayed.
Return value
Returns an HRESULT value.
Remarks
When playing video from networks, the presentation can often be disrupted by network glitches. For this reason, expressing the accuracy of video frames by a simple average is inappropriate. Looking at a standard deviation provides a better idea of the overall accuracy.
Requirements
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | amvideo.h (include Dshow.h) |
| Library | Strmiids.lib |