Hand Held Products 4X00, Руководство пользователя

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10 IMAGETEAM™ 4X00 Series Hardware Interface Layer Specification
InitCaptureICMedia
This function indicates that a transfer will begin on the next Vsync pulse, and the image data will go into the physical memory
location referenced by "hPhysical." This function can be called at any time during a frame, and the driver relies on the hardware
DLL and associated functionality to synchronize to the next Vsync to begin a frame. The Vsync is the border. Anything that
comes in before the front edge of a Vsync will initiate a transfer on the next Vsync. Anything that comes in after that edge of
Vsync will wait for the next Vsync.
Note: The scan driver then assumes that because the Vsync IST runs after this front edge of Vsync, that any calls to
InitCaptureICMedia that are made during the Vsync IST will wait until the front edge of the next Vsync to be initiated
DWORD InitCaptureICMedia(
DWORD hPhysical
)
Passed Arguments Description
DWORD hPhysical A "pseudo-handle" to a reserved physical memory slot. This is the "pseudo-handle"
returned by AllocatePhysicalScanSpaceICMedia when the space was allocated.
Returns
Zero on failure.
1 - capture request was initiated, but it happened just after the front edge of Vsync (i.e., in down time), and therefore will
only take effect on the next front edge of Vsync.
2 - capture request will take effect on next front edge of Vsync.
InitializeImageLineDataProcessingICMedia
This function is used to set up any necessary hardware and or software associated with generating the callback to the data line
processing functionality in the scan driver. This should not enable the calling of this callback. It should only initialize it. To enable
or disable, use the
EnableImageLineDataProcessingICMedia (see page 4), or the
DisableImageLineDataProcessingICMedia (see page 4) function.
DWORD InitializeImageLineDataProcessingICMedia(
void
)
Returns
Zero on failure, non-zero on success.
InitializeVsyncProcessingICMedia
This function configures the hardware and software of the system to respond to the front edge of the Vsync, and put in place the
mechanisms that perform the call of the callback upon the receipt of that edge. The callback functionality is only initialized int his
function, not enabled. (see EnableVsyncProcessingICMedia and DisableVsyncProcessingICMedia).
DWORD InitializeVsyncProcessingICMedia(
void
)
Returns
Zero on failure, non-zero on success.