KSAUDIO_PACKETSIZE_CONSTRAINTS structure (ksmedia.h)
The KSAUDIO_PACKETSIZE_CONSTRAINTS structure describes the physical hardware constraints. It includes an array of 0 or more KSAUDIO_PACKETSIZE_PROCESSINGMODE_CONSTRAINT structures describing constraints specific to any signal processing modes. The driver sets this property before calling PcRegisterSubdevice or otherwise enabling its KS filter interface for its streaming pins.
Syntax
typedef struct _KSAUDIO_PACKETSIZE_CONSTRAINTS {
ULONG MinPacketPeriodInHns;
ULONG PacketSizeFileAlignment;
ULONG Reserved;
ULONG NumProcessingModeConstraints;
KSAUDIO_PACKETSIZE_PROCESSINGMODE_CONSTRAINT ProcessingModeConstraints[ANYSIZE_ARRAY];
} KSAUDIO_PACKETSIZE_CONSTRAINTS;
Members
MinPacketPeriodInHns
The absolute minimum processing period supported by the driver expressed in hundred-nanosecond (HNS) units. This value can be 0 if the driver has no specific minimum processing period.
PacketSizeFileAlignment
The byte size alignment requirement. Use one of these defined file alignment values:
FILE_BYTE_ALIGNMENT
FILE_WORD_ALIGNMENT
FILE_LONG_ALIGNMENT
FILE_QUAD_ALIGNMENT
FILE_OCTA_ALIGNMENT
FILE_32_BYTE_ALIGNMENT
FILE_64_BYTE_ALIGNMENT
FILE_128_BYTE_ALIGNMENT
FILE_256_BYTE_ALIGNMENT
FILE_512_BYTE_ALIGNMENT
Reserved
Unused.
NumProcessingModeConstraints
The number of additional constraints for specific processing modes. This value can be 0.
ProcessingModeConstraints[ANYSIZE_ARRAY]
An array of 0 or more processing mode constraints.
Remarks
The driver sets this variable length data structure as the value of the DEVPKEY_KsAudio_PacketSize_Constraints property on the PnP interface of the KS filter that has the streaming pins with the constraints.
For WaveRT drivers, this data structure describes the constraints for a WaveRT packet. Several WaveRT packets (typically 2) are concatenated to form the WaveRT buffer.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 10 |
| Minimum supported server | Windows Server 2016 |
| Header | ksmedia.h |