PacketSize
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Description

Returns or sets the number of bytes in an isochronous packet


Syntax


[VB]
objActiveDcam.PacketSize [= Value]


[C/C++]
HRESULT get_PAcketSize( long *pPacketSize );
HRESULT put_PacketSize( long PacketSize );



Data Type
[VB]

Long


Parameters
[C/C++]

pPacketSize [out,retval]  
Pointer to the current packet size  
pPacketSize [in]  
The packet size to be set  


Return Values


S_OK  
Success  
E_FAIL  
Failure.  
E_INVALIDARG  
Invalid property value.  
 

Example


This VB example sets the current packet size to 4096 bytes:

ActiveDcam1.PacketSize = 4096
MsgBox ActiveDcam1.PacketSize
 

Remarks


This property is available only for partial scan (Format 7) Modes and related but not necessarily indicative of the effective frame rate. Only certain values of the packet size can be allowed depending on the camera. If the property is set to a value which is not supported by the camera, it will be reset to the nearest allowable packet size.

Note - ActiveDcam supports large packet sizes which exceed 8192 bytes specified by the 1394 standard. This provides full compatibility with high speed dual-packet 1394b cameras such as Point Grey Research Grasshopper 50S5. For more information refer to "IIDC 1394-based Digital Camera Specification, Version 1.31" published by the 1394 Trade Association.