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L_BrightnessDetection

Summary

Finds the brightness amount in a bitmap.

Syntax

#include "l_bitmap.h"

L_LTIMGCOR_API L_INT L_BrightnessDetection(pBitmap, fBrightness, uFlags)

Parameters

pBITMAPHANDLE pBitmap

Pointer to the bitmap handle referencing the bitmap to be tested.

L_FLOAT *fBrightness

Pointer to a variable to be updated with the amount of brightness in the image. Valid values range from 0.0 to 1.0f

L_UINT uFlags

Reserved for future use. Pass 0.

Returns

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

Comments

Support for L_BrightnessDetection is only available in the Document and Medical Imaging toolkits.

This function is useful for filtering out overexposed images captured by portable devices.

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 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.

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

LTIMGCOR
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

L_INT BrightnessDetectionExample(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(TEXT("IMAGE1.CMP")), &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   /* Get the brightness amount in the bitmap */ 
   L_FLOAT fBrightness = 0.0f; 
 
   nRet = L_BrightnessDetection(&LeadBitmap, &fBrightness, 0); 
 
   L_TCHAR  szMsg[200] = { 0 }; 
   wsprintf(szMsg, TEXT("Brightness[%f]\n"), fBrightness); 
   OutputDebugString(szMsg); 
 
   //free bitmap 
   L_FreeBitmap(&LeadBitmap); 
 
   return nRet; 
}