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L_ChangeBitmapSaturation

Summary

Increases or decreases the saturation of colors in a bitmap.

Syntax

#include "l_bitmap.h"

L_LTIMGCLR_API L_INT L_ChangeBitmapSaturation(pBitmap, nChange, uFlags)

Parameters

pBITMAPHANDLE pBitmap

Pointer to the bitmap handle that references the bitmap to be affected.

L_INT nChange

Amount to change saturation. Values are percentages between -1000 and +1000.

Returns

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

Comments

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.

Negative values decrease the saturation of colors. Positive values increase the saturation. The saturation level is increased or decreased by a percentage of its present saturation level. For example, an increase of 20% of the current saturation level "L" will raise the new saturation level "L1" to a value L + 0.20 * L. Likewise, increasing the saturation level 100% doubles the saturation level ( L1 = L + 1.0 * L). Decreasing the saturation level 100% will set the new saturation level to 0. This process is carried out for every pixel.

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 32-bit grayscale images. It returns the error code ERROR_GRAY32_UNSUPPORTED if a 32-bit grayscale image is passed to this function.

Change Saturation Function - Before

Change Saturation Function - After

View additional platform support for this Change Saturation function.

Required DLLs and Libraries

LTIMGCLR
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64, Linux.

Example

For complete sample code, refer to the CHILD.C module of the DEMO
This example loads a bitmap and increases its color saturation.

L_INT ChangeBitmapSaturationExample(L_VOID) 
{ 
   L_INT nRet; 
   BITMAPHANDLE LeadBitmap;   /* Bitmap handle to hold the loaded image. */ 
 
   /* Load the bitmap, keeping the bits per pixel of the file */ 
   nRet = L_LoadBitmap(MAKE_IMAGE_PATH(TEXT("IMAGE1.CMP")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   /* Increase the color saturation by 25 percent  of the possible range */ 
   nRet = L_ChangeBitmapSaturation(&LeadBitmap, 250, 0); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   nRet = L_SaveBitmap(MAKE_IMAGE_PATH(TEXT("Result.BMP")), &LeadBitmap, FILE_BMP, 24, 0, NULL); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   //free bitmap 
   if (LeadBitmap.Flags.Allocated) 
      L_FreeBitmap(&LeadBitmap); 
 
   return SUCCESS; 
}