L_PicturizeBitmap

#include "l_bitmap.h"

L_LTIMG_API L_INT L_PicturizeBitmap(pBitmap, pszDirName, uFlags, nCellWidth, nCellHeight, pfnCallback, pUserData)

Replaces the current image with an image created using images present in the specified directory.

Returns

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.

The image, or selected region, is broken down into rectangles of size nCellWidth x nCellHeight. For each rectangle, the image in the directory that is best suited to replace that rectangle is inserted into the original image.

pBitmap is updated only once for every row of lines, where each line has a height dimension of nCellHeight. Therefore, the pfnCallback can be used to show the progress of every cell. For more information, refer to the PICTURIZECALLBACK callback function.

If a region is selected, only the selected region will be changed by this function. If no region is selected, the whole image will be processed.

On an 8 BPP display, it is recommended that you create a fixed palette before you start the picturize process and use it to paint all the bitmaps. All the bitmaps which will be passed to the picturize callback will be 24BPP so a fixed palette is best. It is faster to create the palette before you start painting rather than creating it every time you paint a little square.

If PICTURIZE_BESTFIT is set, then nCellWidth and nCellHeight are used as a starting point for the actual cell size. The cell sizes are modified so that the size of the last rectangle in a row or column differs from the other rectangles by one. Note that the cell width and height are chosen to be smaller than nCellWidth and nCellHeight. For example, if the bitmap is 101x131 and you pass 32 for the cell width and height and set PICTURIZE_BESTFIT, then the actual cell size will be 25x32. The widths of the cells will be 26, 25, 25, 25 (for a total of 101). The heights of the rows will be 33, 33, 33, 32 (for a total of 131). This option should be used if the bitmap width and height are not multiples of nCellWidth and nCellHeight.

If the bitmap width and height are not multiples of nCellWidth and nCellHeight and PICTURIZE_BESTFIT is not passed, then the last rectangle in a row or column might be very small. Using the example given above, if PICTURIZE_BESTFIT is not set, the widths of the cells would be 32, 32, 32, 5 and the heights would be 32, 32, 32, 32, 3.

PICTURIZE_EQUALUSAGE and PICTURIZE_ONCE will reduce the number of times a bitmap is used by this function.

When PICTURIZE_ONCE is set, the function will try not to use the same bitmap twice. Note that if there arent enough images, the function will return the ERROR_NOT_ENOUGH_IMAGES code if this flag is set.

When PICTURIZE_EQUALUSAGE is set, the function will use the same image more than once only if it is necessary to successfully complete the picturize process. If PICTURIZE_EQUALUSAGE is set, then for any bitmap, the number of times it is used differs from the number of times another bitmap is used by at most one. Therefore, most bitmaps will be used n times, but some bitmaps that will be used n+1 times.

This function supports 12 and 16-bit grayscale and 48 and 64-bit color images. Supportfor 12 and 16-bit grayscale and 48 and 64-bit color images is available only in the Document/Medical 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

Platforms

Windows 2000 / XP/Vista.

See Also

Example

This example will assume that the original bitmap was painted at 100% zoom factor and that there are no scroll bars. It also assumes that we are painting on a display that doesn't need palettes. We imposed all the above limitations for simplicity and to make the code easier to understand.

L_INT EXT_CALLBACK UpdateRectCallback(pBITMAPHANDLE pThumb,
                                      L_UINT        x,
                                      L_UINT        y,
                                      L_VOID      * pUserData) 
{
   HWND  hWnd = (HWND)pUserData;
   RECT  rcDest;
   HDC   hdc = GetDC(hWnd);

   // assume that the original bitmap was viewed at 100% zoom factor.
   // Also assume that we are painting on a 24BPP display. 
   SetRect(&rcDest, x, y, x + pThumb->Width, y + pThumb->Height);

   // paint the bitmap at (x,y) coordinates
   L_PaintDC(hdc, pThumb, NULL, NULL, &rcDest, NULL, SRCCOPY);

   ReleaseDC(hWnd, hdc);

   // return an error code if you want to abort the process
   return SUCCESS;
}

L_INT  PicturizeBitmapExample(HWND hWnd,pBITMAPHANDLE pBitmap)
{
   L_INT nRet;
   FARPROC pfnUpdateRectCallback = MakeProcInstance ((FARPROC)UpdateRectCallback, hInst);

   // Picturize the bitmap in pBitmap 
   //    - use all the images in c:\thumbs directory
   //    - load all images and resize the ones that are not the desired size 
   //    - use 32x32 images 
   //    - use UpdateRectCallback callback to show the progress 
   nRet = L_PicturizeBitmap(pBitmap, 
                           TEXT("C:\\Program Files\\LEAD Technologies\\LEADTOOLS 15\\Images\\thumbs"),
                           PICTURIZE_LOADALL|PICTURIZE_RESIZE,
                           32, 32, 
                           (PICTURIZECALLBACK)pfnUpdateRectCallback, 
                           (L_VOID *)hWnd);
   if(nRet != SUCCESS )
      return nRet;
   FreeProcInstance(pfnUpdateRectCallback);
   
   return SUCCESS;
}