L_SaveBitmapMemory

#include "l_bitmap.h"

L_LTFIL_API L_INT L_SaveBitmapMemory(phHandle, pBitmap, nFormat, nBitsPerPixel, nQFactor, puSize, pSaveOptions)

Saves a bitmap to a file in memory. The output can be in any of the supported compressed or uncompressed file formats.

Returns

Comments

To use this function, do the following:

Support for 12 and 16-bit grayscale images is only available in the Document and Medical Imaging toolkits.

This function cannot be used in combination with L_RedirectIO.

This function supports signed data images, but only DICOM and TIFF formats support signed data. This function will return an error code if you attempt to save a signed image to a format other than DICOM or TIFF.

If the bitmap has a region, the region stored in the bitmap will be saved, if the image is saved as one of the TIFF file formats.

In LEADTOOLS version 17 and up, when saving a colored image (such as a 24-bits per pixel image) to bitonal (1-bit per pixel), the toolkit will not use any dithering when converting the image data. This is done because dithering is not the recommended when converting colored images containing text for document processing such as OCR and Barcode. The result text will be fuzzy and hard for a recognition engine to process. To save a colored image as bitonal with Floyd-Stein dithering (the behavior of LEADTOOLS 16.5 and earlier) use the ESO_USEDITHERINGMETHOD along with BITMAPHANDLE.DitheringMethod as illustrated below:

// 'pBitmap' is a colored BITMAPHANDLE
// Setup FloydStein dithering:
bitmapHandle.DitheringMethod = FLOYD_STEIN_DITHERING;
SAVEFILEOPTION saveOptions = {0};
L_GetDefaultSaveFileOption(&saveOptions, sizeof(SAVEFILEOPTION));
saveOptions.Flags |= ESO_USEDITHERINGMETHOD;
// Save the bitmap as 1-bpp with auto-dithering:
L_SaveBitmap(fileName, &bitmapHandle, FILE_CCITT_GROUP4, 1, 0, &saveOptions);
// or any other L_SaveBitmapXyz or L_SaveFileXyz functions such as:
// L_SaveFile(fileName, &bitmapHandle, FILE_CCITT_GROUP4, 1, 0, 0, NULL, NULL, &saveOptions)

Required DLLs and Libraries

Platforms

Win32, x64, Mobile.

See Also

For a list of functions that utilize the LOADFILEOPTION or SAVEFILEOPTION structures, refer to Functions Utilizing the LOADFILEOPTION or SAVEFILEOPTION structures.

Example

For complete sample code, refer to the SAVEMEM example. This example loads a temporary bitmap, saves it as a file in memory, then loads the memory-resident file into a new bitmap handle.

 L_INT SaveBitmapMemoryExample(L_VOID)
{
   L_INT nRet;
   BITMAPHANDLE LeadBitmap;   /* Bitmap handle for the final image */
   BITMAPHANDLE TmpBitmap;    /* Bitmap handle for the initial image */
   HGLOBAL hFileInMemory = NULL;     /* Memory handle */
   L_SIZE_T uMemSize;   /* Size of the data in memory */
   L_UCHAR  *pData;     /* Pointer to the data in memory */

   /* Load a bitmap at its own bits per pixel  */
   nRet = L_LoadBitmap (MAKE_IMAGE_PATH(TEXT("ImageProcessingDemo\\Image3.cmp")), &TmpBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);
   if(nRet != SUCCESS)
      return nRet;

   /* Save the image as a CMP file in memory */
   nRet = L_SaveBitmapMemory(&hFileInMemory, &TmpBitmap, FILE_CMP, 24, QS, &uMemSize, NULL);
   if(nRet != SUCCESS)
      return nRet;

   /* Free the temporary bitmap */
   if(TmpBitmap.Flags.Allocated)  
      L_FreeBitmap(&TmpBitmap);

   /* Get the pointer to the memory-resident file */
   pData = (L_UCHAR  *) GlobalLock (hFileInMemory);

   /* Load the new bitmap from memory at its own bits per pixel  */
   nRet = L_LoadBitmapMemory (pData, &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, uMemSize, NULL, NULL);
   if(nRet != SUCCESS)
      return nRet;

   /* Clean up */
   GlobalUnlock (hFileInMemory);
   GlobalFree (hFileInMemory);
   L_FreeBitmap(&LeadBitmap);
   return SUCCESS;
}