LJp2FileFormat::ReadFrames

#include "ltwrappr.h"

L_INT LJp2FileFormat::ReadFrames(pszFile, pComposite, pFrames, uNumOfFrames, nBitsPerPixel, nOrder, pLoadOptions, pFileInfo, pReadCallBack, pUserData)

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 */

LFile::LoadFileCallBack 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

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/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 LFile::LoadFileCallBack 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

LJp2FileFormat::ReadFrames 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 LJp2FileFormat::FreeComposite function. Also you must free structure bitmaps by calling the LBitmapBase::Free 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

Win32, x64.

See Also

Functions:

LJp2FileFormat::Read, LJp2FileFormat::ReadList, LJp2FileFormat::ReadComposite, LJp2FileFormat::Save, LJp2FileFormat::SaveList, LJp2FileFormat::SaveComposite, LJp2FileFormat::AppendFrames, LJp2FileFormat::ReadMemory, LJp2FileFormat::ReadListMemory, LJp2FileFormat::ReadCompositeMemory, LJp2FileFormat::ReadFramesMemory, LJp2FileFormat::SaveMemory, LJp2FileFormat::SaveListMemory, LJp2FileFormat::SaveCompositeMemory, LJp2FileFormat::AppendFramesMemory

Topics:

Implementing JPEG 2000 Features

 

Raster Image Functions: Working with JPEG 2000

 

Programming with JPX Features

 

JPX File Comments

 

Raster Image Functions: Working with JPX

Example

This example reads specific frame in JPEG 2000 file format 

#define MAKE_IMAGE_PATH(pFileName) TEXT("C:\\Users\\Public\\Documents\\LEADTOOLS Images\\")pFileName
L_INT LJp2FileFormat__ReadFramesExample(pBITMAPHANDLE pBitmap)
{
   LJp2FileFormat Engine;
   L_INT  nRet;
   L_JP2_JPXCOMPOSITE Composite = {0}; 
   L_UINT32 puFrames[1] = {0};
   Composite.uStructSize = sizeof(L_JP2_JPXCOMPOSITE);
   /*Read a frame*/
   puFrames[0] = 0;
   nRet = Engine.ReadFrames(MAKE_IMAGE_PATH(TEXT("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*/
   Engine.FreeComposite( &Composite);
   return SUCCESS;
}