This callback, if registered, will be called by ImageGear just before a new page is acquired using the IG_TWAIN_acquire(), IG_TWAIN_scan_pages(), IG_TWAIN_scan_pages_to_file() and IG_TWAIN_preview() functions.
Declaration:
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typedef LONG (LPACCUAPI LPFNIG_TWAIN_BEFORE_PAGE)(
LONG nPageNum,
DOUBLE dblLeft,
DOUBLE dblTop,
DOUBLE dblRight,
DOUBLE dblBottom,
LPVOID lpData);
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Arguments:
| nPageNum | Returns the number of the page that is about to be scanned. The page numbering begins with 1. |
| dblLeft | Returns the left coordinate of the selected layout rectangle that will be scanned for the current page. |
| dblTop | Returns the top coordinate of the selected layout rectangle that will be scanned for the current page. |
| dblRight | Returns the right coordinate of the selected layout rectangle that will be scanned for the current page. |
| dblBottom | Returns the bottom coordinate of the selected layout rectangle that will be scanned for the current page. |
| lpData | A far pointer to private data, as specified in your call to IG_TWAIN_CB_register() function. |
Return Value:
Return 1 if you want to continue scanning; return 0 to cancel the scanning process after saving the page just scanned.
Supported Raster Image Formats:
This function does not process image pixels.
Remarks:
This function returns the page number and the bounding image rectangle (image rectangle) within which the scanning will take place, for the page that is about to be scanned.