#include "ltwrappr.h"

virtual L_INT LBitmap::EdgeDetectEffect(uLevel, uThreshold, uFlags)

Performs edge detection on the image.


L_UINT uLevel

Level value used to determine the brightness of the edges. Standard value is 50. Range between 1 and 100. Big values will produce bright edges.

L_UINT uThreshold

Threshold value used to determine which pixels are going to be filtered. If the difference determined for a pixel is less than this value, the pixel is set to 0. If the difference is greater, the filter will be applied to the pixel. The valid ranges are:

L_UINT uFlags

Flag that indicates the type of edge to generate. Possible values are:

Value Meaning
EDGE_SOFT [0] Generate softer (smoother) edges.
EDGE_SOLID [1] Generate rougher edges.


Value Meaning
SUCCESS The function was successful.
< 1 An error occurred. Refer to Return Codes.


This function detects the edges in a bitmap and then replaces the values of edges by new values calculated according to the uFlags.

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.

To update a status bar or detect a user interrupt during execution of this function, refer to LBase::EnableStatusCallback.

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.

Required DLLs and Libraries


Win32, x64.

See Also




L_INT LBitmap__EdgeDetectEffectExample(LBitmap *pLeadBitmap)  
   /* Apply find edges effect on the image*/ 
   return pLeadBitmap->EdgeDetectEffect(50, 0, EDGE_SOFT);  
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