L_Jp2ReadFrames

#include "l_bitmap.h"

L_LTJP2_API L_INT EXT_FUNCTION L_Jp2ReadFrames(hJp2, pszFile, pComposite, pFrames, uNumOfFrames, nBitsPerPixel, nOrder, pLoadOptions, pFileInfo, pReadCallBack, pUserData)

L_HJP2 hJp2;

/* JPEG 2000 engine handle */

L_TCHAR * pszFile;

/* JPEG 2000 file name */

pL_JP2_JPXCOMPOSITE pComposite;

/* pointer to a L_JP2_JPXCOMPOSITE structure */

L_UINT32 * pFrames;

/* frames indices */

L_UINT32 uNumOfFrames;

/* number of frames */

L_INT nBitsPerPixel;

/* resulting bitmaps pixel depth */

L_INT nOrder;

/* desired color order */

pLOADFILEOPTION pLoadOptions;

/* pointer to optional extended load options */

pFILEINFO pFileInfo;

/* pointer to a structure */

FILEREADCALLBACK pReadCallBack;

/* optional callback function */

L_VOID * pUserData;

/* pointer to more parameters for the callback */

Loads the specified frames bitmaps (Color, Opacity and Pre-multiplied opacity) stored in the specified JPEG 2000 file.

Parameter

Description

hJp2

JPEG 2000 engine handle that was created by the L_Jp2Create function.

pszFile

Character string that contains the name of the JPEG 2000 file.

pComposite

Pointer to the L_JP2_JPXCOMPOSITE structure that references L_JP2_JPXBITMAPS bitmaps to be filled with image data.

pFrames

Frames indices. An array of unsigned integers specifies the indices of the frames to be loaded from the file.

uNumOfFrames

Number of frames to be loaded. This value specifies the size of pFrames.

nBitsPerPixel

Resulting bitmap pixel depth. If zero [0], the bitmap will have the original files pixel depth (do not convert).

nOrder

The desired color order. Possible values are:

Value

Meaning

ORDER_RGB

[0] Read-green-blue order.

ORDER_BGR

[1] Blue green-red order.

ORDER_GRAY

[2] 12 or 16-bit grayscale image. 12 and 16-bit grayscale images are supported in Document and Medical imaging products only.

0

The data is 8 bits per pixel or less.

ORDER_RGBORGRAY

[3] Load the image as red, green, blue, OR as a 12 or 16-bit grayscale image. 12 and 16-bit grayscale images are supported in Document/Medical imaging products only.

ORDER_BGRORGRAY

[4] Load the image as blue, green, red, OR as a 12 or 16-bit grayscale image. 12 and 16-bit grayscale images are supported in Document/Medical imaging products only.

ORDER_ROMM

[5] ROMM order. ROMM only supports 24 and 48-bit images.

ORDER_BGRORGRAYORROMM

[6] Load the image as blue, green, red, OR as a 12 or 16-bit grayscale image OR as ROMM. 12 and 16-bit grayscale images are supported in Document/Medical imaging products only.

pLoadOptions

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

pFileInfo

Pointer to a FILEINFO structure. If nothing is known about the file pass NULL.

pReadCallBack

Optional callback function for additional processing.

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

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

The callback function must adhere to the function prototype described in the FILEREADCALLBACK function.

pUserData

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

Returns

SUCCESS

The function was successful.

< 1

An error occurred. Refer to Return Codes.

Comments

L_Jp2ReadFrames loads the specified frames bitmaps (Color, Opacity and Pre-multiplied opacity) stored in the specified JPEG 2000 file. You must free this structure by calling the L_Jp2FreeComposite function. Also you must free structure bitmaps by calling the L_FreeBitmap function. All of the engines boxes will be reset.

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

Windows 2000 / XP/Vista.

See Also

Functions:

L_Jp2Read, L_Jp2ReadList, L_Jp2ReadComposite, L_Jp2Save, L_Jp2SaveList, L_Jp2SaveComposite, L_Jp2AppendFrames, L_Jp2ReadMemory, L_Jp2ReadListMemory, L_Jp2ReadCompositeMemory, L_Jp2ReadFramesMemory, L_Jp2SaveMemory, L_Jp2SaveListMemory, L_Jp2SaveCompositeMemory, L_Jp2AppendFramesMemory

Topics:

Programming with JPEG 2000 Features
Raster Image Functions: Working with JPEG 2000

Example

This example reads specific frame in JPEG 2000 file format

L_LTJP2TEX_API L_INT Jp2ReadFramesExample(pBITMAPHANDLE pBitmap)
{
   L_HJP2 hEngine;
   L_INT  nRet;
   L_JP2_JPXCOMPOSITE Composite = {0}; 
   L_UINT32 puFrames[1] = {0};

   Composite.uStructSize = sizeof(L_JP2_JPXCOMPOSITE);

   /*Create JPEG  2000 engine handle*/
   hEngine = L_Jp2Create();
   
   /*Read a frame*/
   puFrames[0] = 0;
   nRet = L_Jp2ReadFrames(hEngine,TEXT("%UserProfile%\\My Documents\\LEADTOOLS Images\\image1.jpx"),&Composite,puFrames,1,24,ORDER_BGR,NULL,NULL,NULL, NULL);
   if(nRet != SUCCESS)
      return nRet;

   *pBitmap = Composite.pBitmaps[0].ColorBitmap;

   /*Free comoposite structure*/
   L_Jp2FreeComposite(hEngine, &Composite);
   /*Destroy engine handle*/
   L_Jp2Destroy(hEngine);

   return SUCCESS;
}