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.
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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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| Name | Type | Description |
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| nPageNum | LONG | Returns the number of the page that is about to be scanned. The page numbering begins with 1. |
| dblLeft | DOUBLE | Returns the left coordinate of the selected layout rectangle that will be scanned for the current page. |
| dblTop | DOUBLE | Returns the top coordinate of the selected layout rectangle that will be scanned for the current page. |
| dblRight | DOUBLE | Returns the right coordinate of the selected layout rectangle that will be scanned for the current page. |
| dblBottom | DOUBLE | Returns the bottom coordinate of the selected layout rectangle that will be scanned for the current page. |
| lpData | LPVOID | A far pointer to private data, as specified in your call to IG_TWAIN_CB_register() function. |
Return 1 if you want to continue scanning; return 0 to cancel the scanning process after saving the page just scanned.
This function does not process image pixels.
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.