| Microsoft DirectX 8.1 (C++) |
The Tee/Sink-to-Sink Converter is a kernel-mode, KsProxy-based filter. It is used in analog video television filter graphs where VBI data is being rendered or captured. The filter is connected upstream to the WDM Video Capture Filter and provides an efficient means to duplicate streams of data within kernel mode without the expensive transitions between kernel and user mode. It delivers each received data block to all output pins, and the downstream codec is responsible for finding the specific VBI data to decode.
The other important function of the Tee/Sink-to-Sink Converter is not really relevant for application programmers, but is mentioned here for completeness. The "Sink-to-Sink" capability was required for the Microsoft® Windows 98® platform to enabled the connection of two drivers that each supported only incoming IRPs. This functionality is now performed by other components in the WDM architecture.
The Tee/Sink-to-Sink Converter appears in GraphEdit under the "WDM Streaming Tee/Splitter Devices" category. Because this is a kernel-mode filter, applications cannot co-create it directly, but must use the System Device Enumerator to instantiate it, as described in Enumerating Devices and Filters.