LJp2FileFormat::SaveCompositeMemory

Summary

Creates a file in memory in any of the supported JPEG 2000 file formats, using the layer information you provide in pComposite.

Syntax

#include "ltwrappr.h"

L_INT LJp2FileFormat::SaveCompositeMemory(lpBuffer, puBufferSize, pComposite, eFormat, nBitsPerPixel, nQFactor, pSaveOptions, pSaveCallBack, pUserData)

Parameters

L_UINT8 ** lpBuffer

Pointer to a memory buffer pointer that will be updated with a new memory buffer pointer that contains the saved image. You must free this buffer by calling the Windows LocalFree() function.

L_SIZE_T *puBufferSize

Address of a variable to be updated with the size of the memory buffer in bytes.

pL_JP2_JPXCOMPOSITE pComposite

Pointer to the L_JP2_JPXCOMPOSITE structure that provides information (color, opacity, pre-opacity, and compression) for all layers to be saved.

eJP2FILEFORMAT eFormat

Output JPEG 2000 file format.

L_INT nBitsPerPixel

Resulting files pixel depth. Possible values are: 8, 12, 16, 24, 32, 48, 64, and 0. Zero [0] means that each bitmap will be saved with its bits per pixel value, if that value is equal to one of the possible values (8, 12, 16, 24, 32, 48, or 64). If it is not one of the possible values, it will return: ERROR_J2K_UNSUPPORTED.

L_INT nQFactor

Quality factor. This value determines the degree of loss in the compression process. Possible values are from 0 to 255. Zero (0) represents lossless compression. Values between 1 and 255 are interpreted as a compression ratio.

pSAVEFILEOPTION pSaveOptions

Pointer to optional extended save options. Pass NULL to use the default save options.

LFile::SaveFileCallBack pSaveCallBack

Optional callback function for additional processing.

If you do not provide a callback function, pass NULL.

If you provide a callback function, use the function pointer as the value of this parameter.

The callback function must adhere to the syntax described in LFile::SaveFileCallBack.

L_VOID * pUserData

Void pointer you can use to pass one or more additional parameters used by the callback function.

To use this feature, assign a value to a variable or create a structure that contains as many fields as you need. Then, in this parameter, pass the address of the variable or structure, casting it to L_VOID *. The callback function, which receives the address in its own pUserData parameter, can cast it to a pointer of the appropriate data type to access your variable or structure.

If additional parameters are not needed, pass NULL.

Returns

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

Comments

LJp2FileFormat::SaveCompositeMemory creates a file in memory in any of the supported JPEG 2000 file formats, using the layer information you provide in pComposite. The color bitmap must be allocated in all layers. If any color bitmap is not allocated, the function will return: ERROR_NO_BITMAP. All of the engines boxes will be reset. The JPEG 2000 part 1 (JP2) file format supports only one layer. If you set more than one layer in pComposite, only the first layer will be saved. Also, the JPEG 2000 part 1 (JP2) file format does not support multiple codestreams, so only the color bitmap will be saved. All of the currently-set engines boxes will also be saved in this file.

Required DLLs and Libraries

LTJP2
LFJ2K
LTIMGEFX
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.

Example

This example saves/loads composite bitmaps in JPEG 2000 file format

L_INT LJp2FileFormat__SaveCompositeMemoryExample(pL_JP2_JPXCOMPOSITE pComposite, L_UINT8 * pXMLData, L_SIZE_T uSize) 
{ 
   LJp2FileFormat Engine; 
   L_INT  nRet; 
   L_UINT i; 
   L_JP2_XML_BOX XMLBox; 
   L_UINT8* pFileBuffer; 
   L_SIZE_T uFileSize; 
   L_JP2_JPXCOMPOSITE Composite = {0}; 
 
   /*Create an XML box*/ 
   XMLBox.uStructSize = sizeof(L_JP2_XML_BOX); 
   XMLBox.pData = pXMLData; 
   XMLBox.uDataSize = uSize; 
 
   /*Set XML box of JPX engine*/ 
   nRet = Engine.SetBoxes(L_JPXB_XML,&XMLBox,1); 
   if(nRet != SUCCESS) 
      return nRet; 
 
 
   /*Save the image in JPx format*/ 
   nRet = Engine.SaveCompositeMemory( &pFileBuffer, &uFileSize, pComposite,LEADJP2_JPX, 24, 5,NULL, NULL, NULL); 
   if(nRet != SUCCESS) 
      return nRet; 
 
   Composite.uStructSize = sizeof(L_JP2_JPXCOMPOSITE); 
   /*Load the compiste images*/ 
   nRet = Engine.ReadCompositeMemory( pFileBuffer, uFileSize, &Composite,0,ORDER_BGR,NULL, NULL, NULL, NULL); 
   if(nRet != SUCCESS) 
      return nRet; 
 
   /*Free the read composite bitmaps*/ 
   for(i = 0; i < Composite.uNumOfBitmaps; i++) 
   { 
      if(Composite.pBitmaps[i].ColorBitmap.Flags.Allocated) 
         L_FreeBitmap(&Composite.pBitmaps[i].ColorBitmap); 
      if(Composite.pBitmaps[i].OpacityBitmap.Flags.Allocated) 
         L_FreeBitmap(&Composite.pBitmaps[i].OpacityBitmap); 
      if(Composite.pBitmaps[i].PreOpacityBitmap.Flags.Allocated) 
         L_FreeBitmap(&Composite.pBitmaps[i].PreOpacityBitmap); 
   } 
 
   /*Free composite structure*/ 
   nRet = Engine.FreeComposite( &Composite); 
   if(nRet != SUCCESS) 
      return nRet; 
 
 
   GlobalFree(pFileBuffer); 
   return SUCCESS; 
}