I am tring to get the image data from a Video Capture card. The SDK is a DLL and an .h file. I met some problems when I am using the Call Library Function Node for a function. The function was described like this:
Function Name: int RegisterStreamDirectReadCallback(STREAM_DIRECT_READ_CALLBACK StreamDirectReadCallback, void* Context)
Parameter: STREAM_DIRECT_READ_CALLBACK StreamDirectReadCallback
Callback function explanation:
typedef int (* STREAM_DIRECT_READ_CALLBACK)(ULONG channelNumber, void * DataBuf,DWORD Length, int FrameType,void *context);
ULONG channelNumber channel number
void* DataBuf buffer address
DWORD Length buffer length
int FrameType buffer type
void* context device context
so how can I define the parameters in the Call Labrary Function Node for this ?
I'd recommend taking a look at this community example, Calling C/++ DLLs Containing Simple and Complex Data Types from LabVIEW
I'm most concerned about the DWORD data type--what errors does it throw when you try to get the DLL to work with it or what performance are you seeing?