pciGrabber-4x4
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PHYTEC Messtechnik GmbH 2008 L-720e_0
The parameter
dwBitsSize
defines the whole size of the required
memory region of the image. This is calculated from the number of
pixels and the number of pixels per Byte:
hsize
vsize
pixel size.
Please pay attention that
dwBitsSize
is the size of the
complete
memory region required for the image. If even- and odd-fields are dig-
itized separately, you have to add the memory region for both fields.
More information on calculating memory requirements can be found
under the command
SetImage().
Activate Interrupt
DWORD ActivateFieldInterrupt (WORD nDevNo,
HANDLE *hEvent);
HANDLE : Pointer to an Event
Monitoring the progress of image digitizing can also be done using the
hardware-interrupt of the framegrabber. An interrupt can be generated
at the end of every field.
The interrupt ist signaled to the software by the generation of an event.
Waiting for this event is a method to monitor the digitization progress
without polling the status flags (see
DataPresent()
).
The function
ActivateFieldInterrupt()
sets up the interrupt
configuration of the grabber card and activates the hardware interrupt.
It creates the event and returns a pointer (handle) to this event.
You can monitor this event by using the Windowa API-function
WaitForSingleObject()
. Please note, that the event has to be reset by
calling the function
ResetEvent().
Otherwise, new events can not be
signaled.
Important:
•
The event is signaled every time the digitizing of a field is finished.
This happens only, if the digitization has been started
(
Start_Grabber()
). After the occurrence of the field end, the signal
remains active until it is reset by calling
ResetEvent()
. This enables
