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Stream Categories

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The KsProxy filter supports several types of stream categories. The tables in the following subsections describe the different types of stream categories and the data formats associated with each type of category, as well as the extended header size value that a video capture minidriver should specify per category.

A Stream class video capture minidriver provides stream category and content information in response to an SRB_GET_STREAM_INFO request. The minidriver returns information about each stream category it supports in a HW_STREAM_INFORMATION structure.

Within the HW_STREAM_INFORMATION structure is a StreamFormatsArray member, which has an entry for each unique data format that the minidriver provides for the specified stream category. Each StreamFormatsArray entry contains stream format information, including image characteristics, such as color format, bit depth, cropping, and scaling information. Also included in the StreamFormatsArray member is the range of formats available for the specified stream category.

For each video stream category there are corresponding KSDATAFORMAT and KSDATARANGE structures to be used when describing the stream in the HW_STREAM_INFORMATION structure. The structures that correspond to stream categories are listed in the tables in the following subsections.

The stream category GUID and pin name GUID for a given video capture stream type are usually identical. These GUIDs are specified in the Category and Name members of the HW_STREAM_INFORMATION structure, respectively. The only case where these GUIDs do not match is when a given stream category has more than one instance on a filter. In this case, the category GUIDs should match, but each pin should be assigned a unique pin name GUID.

The following subsections contain information about each of the different video capture stream categories. The stream category GUID and pin name GUID are described, as well as the structures that should be used to support the category. Required property set support is also listed for each category. The corresponding user-mode DirectShow type information is also listed for convenience.