LEADTOOLS Raster imaging C++ Class library help
| LEADTOOLS Raster Imaging C++ Class Library Help > Classes and Member Functions > LBitmap > LBitmap Member Functions > LBitmap::EdgeDetector |
#include "ltwrappr.h"
virtual L_INT LBitmap::EdgeDetector (uThreshold, uFilter, uFlags = 0)
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L_UINT uThreshold; |
/* threshold value */ |
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L_UINT uFilter; |
/* filter to be used */ |
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L_UINT32 uFlags; |
/* flags */ |
Applies the specified edge filter to the class object's bitmap.
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Parameter |
Description |
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uThreshold |
Threshold value used to determine which pixels are edge pixels. If the difference determined for a pixel is greater than this value, the pixel is an edge pixel. |
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uFilter |
Flag that indicates which edge detection filter to apply. Possible values are: |
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Value |
Meaning |
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EDG_SOBEL_VERT |
[0x0101] Detect the vertical edges |
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EDG_SOBEL_HORZ |
[0x0102] Detect the horizontal edges |
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EDG_SOBEL_ALL |
[0x0103] Detect horizontal & vertical edges |
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EDG_PREWITT_VERT |
[0x0201] Detect the vertical edges |
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EDG_PREWITT_HORZ |
[0x0202] Detect the horizontal edges |
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EDG_PREWITT_ALL |
[0x0203] Detect horizontal & vertical edges |
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EDG_LAPLACE_1 |
[0x0301] Detect vertical & horizontal edges |
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EDG_LAPLACE_2 |
[0x0302] Detect general edges |
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EDG_LAPLACE_3 |
[0x0303] Detect general edges. (The filter used for this option is different than the filter used for the EDG_LAPLACE_2 filter.) |
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EDG_LAPLACE_DIAG |
[0x0304] Detect the diagonal edges |
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EDG_LAPLACE_HORZ |
[0x0305] Detect the horizontal edges |
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EDG_LAPLACE_VERT |
[0x0306] Detect the vertical edges |
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EDG_GRADIENT_N |
[0x0401] Detect north edges |
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EDG_GRADIENT_NE |
[0x0402] Detect north east edges |
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EDG_GRADIENT_E |
[0x0403] Detect east edges |
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EDG_GRADIENT_SE |
[0x0404] Detect south east edges |
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EDG_GRADIENT_S |
[0x0405] Detect south edges |
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EDG_GRADIENT_SW |
[0x0406] Detect south west edges |
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EDG_GRADIENT_W |
[0x0407] Detect west edges |
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EDG_GRADIENT_NW |
[0x0408] Detect north west edges |
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uFlags |
Reserved for future use. Must be 0. |
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Returns
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SUCCESS |
The function was successful. |
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< 1 |
An error occurred. Refer to Return Codes. |
Comments
Filters such as Sobel filter, Prewitt filter, Laplacian filter, and Gradient filter are used to determine the pixels belonging to edges in the bitmap.
This function can process the whole image or a region of the image.
This function supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale and 48 and 64-bit color images is available only in the Document/Medical toolkits.
The threshold range for the 16, 48, and 64-bit bitmaps is from 0 to 65535 and for 12-bit bitmaps from 0 to 4095. Otherwise, it is from 0 to 255. The threshold is applied on channels separately.
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.
Required DLLs and Libraries
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LTDIS For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application. |
Win32, x64.
See Also
Example
L_INT LBitmap__EdgeDetectorExample(LBitmap & Bitmap, L_TCHAR * szFile)
{
L_INT nRet;
nRet =Bitmap.Load(szFile);
if(nRet !=SUCCESS)
return nRet;
nRet =Bitmap.EdgeDetector(60, EDG_SOBEL_ALL);
if(nRet !=SUCCESS)
return nRet;
return SUCCESS;
}
