IAMStats interface (control.h)
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The IAMStats interface retrieves performance data from the Filter Graph Manager. Filters can use this interface to record performance data.
Filter developers: As with all Filter Graph Manager interfaces, a filter must not hold a reference count on this interface, or it will cause a circular reference count. For more information, see IBaseFilter::JoinFilterGraph.
Inheritance
The IAMStats interface inherits from the IDispatch interface. IAMStats also has these types of members:
Methods
The IAMStats interface has these methods.
| IAMStats::AddValue The AddValue method records a new value. |
| IAMStats::get_Count The get_Count method retrieves the number of statistics. |
| IAMStats::GetIndex The GetIndex method retrieves the index for a named statistic, or creates a new statistic. |
| IAMStats::GetValueByIndex The GetValueByIndex method retrieves a statistic, by index. |
| IAMStats::GetValueByName The GetValueByName method retrieves a statistic, by name. |
| IAMStats::Reset The Reset method resets all statistics to zero. |
Remarks
Each statistic is defined by a name and an index. Use the GetIndex method to find the index from the name. Values are always double types. The following statistics are predefined.
| Name | Description |
|---|---|
| RenderFile | Measures the time taken by each call to IGraphBuilder::RenderFile. |
| ConnectDirectInternal | Measures the time taken to connect two filters. |
| Build Mapper Cache | Measures the time taken to cache information about registered filters (used by the Filter Mapper object). |
| Process Category CategoryName | Measures the time taken to cache information about filters in a particular category, where CategoryName is the friendly name of the filter category. (See Filter Categories.) |
For each of these statistics, the values represent time in milliseconds.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP [desktop apps only] |
| Minimum supported server | Windows Server 2003 [desktop apps only] |
| Target Platform | Windows |
| Header | control.h (include Dshow.h) |