Microsoft DirectX 8.0 |
The Line 21 Decoder filter accepts line21 data in either the standard byte pair format or, in the case of DVD, as a packet for the whole group of pictures (GOP). For every GOP in the DVD video stream, there can be a user data packet that has that particular GOP's header information and line 21 data.
On the input pin the filter connects to any line21 data provider, e.g., a DVD video decoder that has a line21 data output pin, or the CC Decoder WDM filter (via KsProxy) that provides line21 data from the VBI stream coming into a TVTuner/video capture card.
The filter decodes the line 21 data into bitmaps and passes them to the downstream filter, either to a secondary pin on the Overlay Mixer or to the Video Renderer. (The Overlay Mixer's primary pin always takes the main video stream.)
The following diagram shows a typical DVD filter graph using the Line 21 Decoder.
Filter Interfaces | IAMLine21Decoder |
---|---|
Input Pin Media Types | Major Type: MEDIATYPE_AUXLine21Data Subtype:
|
Input Pin Interfaces | None. |
Output Pin Media Types | Major type: MEDIATYPE_Video Subtype:
|
Output Pin Interfaces | None. |
Filter CLSID | CLSID_Line21Decoder |
Property Page CLSID | None |
Executable | qdvd.dll |
Merit | MERIT_NORMAL |
Category | CLSID_LegacyAmFilterCategory |