Video Capture Minidriver Property Sets
This section describes the video capture-specific property sets that are available for video capture minidrivers that use WDM kernel-streaming services in Microsoft Windows XP, Windows 2000, and Windows 98/Me and later operating systems.
The reference page for each property contains a table with the following column headings.
Get | Set | Target | Property descriptor type | Property value type |
---|---|---|---|---|
These headings have the following meanings:
Get
Does the target KS object support the KSPROPERTY_TYPE_GET property request?
Set
Does the target KS object support the KSPROPERTY_TYPE_SET property request?
Target
The target is the KS object to which property request is sent. The target for a video capture property is either a filter or a pin. (The property request specifies the target object by its kernel handle.)
Property descriptor type
The property descriptor specifies the property and the operation to perform on that property. The descriptor always begins with a KSPROPERTY structure, but some types of descriptor contain additional information. For example, the KSNODEPROPERTY structure is a property descriptor that begins with a KSPROPERTY structure but also includes a node identifier.
Property value type
A property has a value and the type of this value depends on the property. For example, a property that can be in one of only two states--on or off--typically has a BOOL value. A property that can assume integer values from 0x0 to 0xFFFFFFFF might have a ULONG value. More complex properties might have values that are arrays or structures.
The property descriptor and property value above are the property-specific versions of the instance-specification and operation-data buffers that KS Properties, Events, and Methods discusses.
A property request uses one of the following flags to specify the operation to be performed on the property:
KSPROPERTY_TYPE_BASICSUPPORT
KSPROPERTY_TYPE_GET
KSPROPERTY_TYPE_SET
All filter and pin objects support the basic-support operation on their properties. Whether they support the get and Set operations depends on the property. A property that represents an inherent capability of the filter or pin object is likely to require only a get operation. A property that represents a configurable setting might require only a Set operation, although a get operation might also be useful for reading the current setting. For more information about using the get, set, and basic-support operations with video capture properties, see KS Properties.
Every property description contains a table that indicates whether video capture minidrivers must support reading or writing the property. Video capture minidrivers should return STATUS_NOT_SUPPORTED in response to get or set requests for properties that are not supported by the minidriver.
The following list describes kernel streaming property sets that video capture minidrivers use:
PROPSETID_VIDCAP_CAMERACONTROL
KSPROPERTYSETID_ExtendedCameraControl
PROPSETID_VIDCAP_DROPPEDFRAMES
PROPSETID_VIDCAP_VIDEOCOMPRESSION
The following property sets can be used with the USB Video Class Driver:
PROPSETID_VIDCAP_CAMERACONTROL