L_LTIMGCOR_API L_INT EXT_FUNCTION L_BlankPageDetectorBitmap(pBitmap, pOptions, uFlags)
Determines whether the scanned image is a blank page.
Pointer to the bitmap handle that references the image to be tested.
Pointer to a BLANKPAGEDETECTOROPTIONS structure containing options for detecting whether an image is a blank page.
Flags that indicate how to consider blank pages and the function behavior. You can combine values when appropriate by using a bitwise OR ( | ). Possible values are:
Value | Meaning |
---|---|
BLANK_DETECT_EMPTY | [0x00000000] A page must be totally blank. |
BLANK_DETECT_NOISY | [0x00000001] A page may have some noise. This is the default value. |
Value | Meaning |
---|---|
BLANK_NOT_BLEED_THROUGH | [0x00000000] Do not ignore bleed through from the page. |
BLANK_BLEED_THROUGH | [0x00000010] Ignore bleed through from the page. This is the default value. |
Value | Meaning |
---|---|
BLANK_DONT_DETECT_LINES | [0x00000000] Do not consider lined page as a blank page. This is the default value. |
BLANK_DETECT_LINES | [0x00000100] Consider lined page as a blank page. |
Value | Meaning |
---|---|
BLANK_DONT_USE_ACTIVE_AREA | [0x00000000] Do not ignore blank spaces around the page edges. This is the default value. |
BLANK_USE_ACTIVE_AREA | [0x00001000] Ignore blank spaces around the page edges. |
Value | Meaning |
---|---|
BLANK_DEFAULT_MARGIN | [0x00000000] Use default margins, which are computed automatically by the function based on the page dimensions. This is the default value. |
BLANK_USER_MARGIN | [0x00010000] Use the user-specified margins, which are specified in PMargins. |
Value | Meaning |
---|---|
SUCCESS | The function was successful. |
< 1 | An error occurred. Refer to Return Codes. |
Scanned images can contain blank (empty) pages. This function determines whether the scanned image is a blank page or not, detects noisy, bleed through, and lined blank pages with high precision and speed, and provides a percentage accuracy of the result. This function helps reduce the disk storage space required for scanned images.
This function does not support signed data images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image is passed to this function.
This function does not support 32-bit grayscale images. It returns the error code ERROR_GRAY32_UNSUPPORTED if a 32-bit grayscale image is passed to this function.
Win32, x64, Linux.
L_INT BlankPageDetectorBitmapExample(L_VOID)
{
L_INT nRet;
BITMAPHANDLE LeadBitmap; /* Bitmap handle hold the loaded image. */
/* Load the bitmap, keeping the bits per pixel of the file */
nRet = L_LoadBitmap (MAKE_IMAGE_PATH("IMAGE1.CMP"), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);
if(nRet !=SUCCESS)
return nRet;
/* Check if the image is a blank page */
BLANKPAGEDETECTOROPTIONS Options = { 0 };
Options.uStructSize = sizeof BLANKPAGEDETECTOROPTIONS;
Options.bIsBlank = 1;
Options.uAccuracy = 0;
nRet = L_BlankPageDetectorBitmap(&LeadBitmap, &Options,
BLANK_DETECT_NOISY | BLANK_BLEED_THROUGH | BLANK_DEFAULT_MARGIN);
if (Options.bIsBlank)
OutputDebugString(L_TEXT("Image is blank.\n"));
else
OutputDebugString(L_TEXT("Image is not blank.\n"));
//free bitmap
L_FreeBitmap(&LeadBitmap);
return nRet;
}
Help Collections
Raster .NET | C API | C++ Class Library | HTML5 JavaScript
Document .NET | C API | C++ Class Library | HTML5 JavaScript
Medical .NET | C API | C++ Class Library | HTML5 JavaScript
Medical Web Viewer .NET
Multimedia
Direct Show .NET | C API | Filters
Media Foundation .NET | C API | Transforms
Supported Platforms
.NET, Java, Android, and iOS/macOS Assemblies
Imaging, Medical, and Document
C API/C++ Class Libraries
Imaging, Medical, and Document
HTML5 JavaScript Libraries
Imaging, Medical, and Document