#include "l_bitmap.h"

L_LTIMGSFX_API L_INT EXT_FUNCTION L_ColoredPencilBitmapExt(pBitmap, uSize, uStrength, uThreshold, uPencilRoughness, uStrokeLength, uPaperRoughness, nAngle, uFlags)

Applies an effect to a bitmap that makes it look like it has been drawn with colored pencils.



Pointer to the bitmap handle that references the bitmap on which to apply the effect.

L_UINT uSize

Size of the neighborhood used to determine the width of the outlines.

L_UINT uStrength

Strength factor used to create the "outline". This can be any number that is 0 or greater.

L_UINT uThreshold

Threshold value used to determine which pixels are edge pixels (outlines). If the difference determined for a pixel is greater than this value, the pixel is an edge pixel. Valid values range from 0 through 65535 for 64-bit, 48-bit and 16-bit grayscale images and from 0 through 4095 for 12-bit grayscale images. Otherwise, it is from 0 to 255. Use this parameter to control the number of edge pixels found.

L_UINT uPencilRoughness

Percentage of coloring coverage (colored pencil roughness), expressed in tenths of a percent. Valid values range from 0 to 1000.

L_UINT uStrokeLength

Length of the colored pencil stroke, in pixels.

L_UINT uPaperRoughness

Percentage of paper surface roughness, expressed in tenths of a percent. Valid values range from 0 to 1000.

L_INT nAngle

Value that represents the direction of the coloring motion, in hundredths of a degree (+/-) This value can be a number from -18000 to 18000. This parameter is ignored when uFlags = ARTISTIC_COLOREDPENCIL.

L_UINT uFlags

Flags that determine which the type of direction to use and whether to combine the resulted bitmap with the original one or not. You can specify one flag or combine both groups of flags by using a bitwise OR ( | ). The following flags indicate which type of direction to use:

Value Meaning
ARTISTIC_COLOREDPENCIL [0x01] The coloring is more artistic, since no certain direction dominates the whole image.
DIRECTIONAL_COLOREDPENCIL [0x02] The coloring motion is directed in a certain direction determined by the nAngle value.

The following flag indicates whether to combine the resulted bitmap with the original one. If you do not want to combine the two,  ignore this group.

Value Meaning
COMBINE_ORIGINAL [0x10] Combines the resulted bitmap with the original one.


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


This function is like the L_ColoredPencilBitmap function, but has been extended to produce more realistic results.

For an example, click here

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 in the Document and Medical Imaging toolkits.

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

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




The following example loads a bitmap and applies the extended colored pencil effect:

L_INT ColoredPencilBitmapExtExample(L_VOID) 
   L_INT nRet; 
   /* Bitmap handle to hold the loaded image. */ 
   BITMAPHANDLE LeadBitmap; 
   /* Load the bitmap, keeping the bits per pixel of the file */ 
   nRet = L_LoadBitmap(MAKE_IMAGE_PATH(TEXT("ImageProcessingDemo\\NaturalFruits.jpg")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL); 
   if(nRet !=SUCCESS) 
      return nRet; 
   nRet = L_ColoredPencilBitmapExt(&LeadBitmap,  5, 4, 0, 250, 15, 100, 0, ARTISTIC_COLOREDPENCIL); 
   if(nRet !=SUCCESS) 
      return nRet; 
   nRet = L_SaveBitmap(MAKE_IMAGE_PATH(TEXT("ImageProcessingDemo\\Result.BMP")), &LeadBitmap, FILE_BMP, 24, 0, NULL); 
   if(nRet !=SUCCESS) 
      return nRet; 
   // free bitmap  
   return SUCCESS; 

Help Version 21.0.2021.4.7
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2021 LEAD Technologies, Inc. All Rights Reserved.

LEADTOOLS Raster Imaging C API Help