LEADTOOLS Raster Imaging C DLL Help > Function References > L_Jp2ReadBox |
#include "l_bitmap.h"
L_LTJP2_API L_INT EXT_FUNCTION L_Jp2ReadBox(hJp2, pszFile, eBoxType, plBox, uBoxIndex)
L_HJP2 hJp2; |
/* JPEG 2000 handle */ |
L_TCHAR * pszFile; |
/* JPEG 2000 file name */ |
eJP2BOXTYPE eBoxType; |
/* box type */ |
L_VOID ** plBox; |
/* pointer to a pointer */ |
L_UINT32 uBoxIndex; |
/* box index */ |
Reads a box of type eBoxType at uBoxIndex from 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. |
eBoxType |
Box type. It specifies the type of the box to be read from the file. |
plBox |
Pointer to a pointer to be updated with the box data structure. |
uBoxIndex |
0-based box index. It specifies the box to read. |
Returns
SUCCESS |
The function was successful. |
< 1 |
An error occurred. Refer to Return Codes. |
Comments
L_Jp2ReadBox reads a box of type eBoxType at uBoxIndex from the specified JPEG 2000 file.
If the uBoxIndex is greater than the number of boxes, the function returns: ERROR_INV_PARAMETER.
L_JP2B_RESOLUTION and L_JPXB_RESOLUTION boxes cant be read using this function. All of the engines boxes will be reset and updated with the new loaded boxes only.
You must free the allocated box by calling the L_Jp2FreeBoxes function.
Required DLLs and Libraries
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: |
L_Jp2FreeBoxes, L_Jp2ReadBoxMemory, L_Jp2AppendBoxes, L_Jp2AppendBoxesMemory |
Topics: |
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Example
This example reads an MPEG7 box stored in a JPEG 2000 file.
#define MAKE_IMAGE_PATH(pFileName) TEXT("C:\\Users\\Public\\Documents\\LEADTOOLS Images\\")pFileName L_LTJP2TEX_API L_INT Jp2ReadBoxExample(L_UINT8 ** pMPEG7Data, L_SIZE_T* puSize) { L_HJP2 hEngine; L_INT nRet; pL_JP2_MPEG7_BOX pMPEG7Box; L_JP2_FILEINFO Jp2FileInfo; /*Create JPEG 2000 engine handle*/ hEngine = L_Jp2Create(); Jp2FileInfo.uStructSize = sizeof(L_JP2_FILEINFO); L_Jp2GetFileInfo(hEngine, MAKE_IMAGE_PATH(TEXT("image1.jpx")),&Jp2FileInfo); if(Jp2FileInfo.MPEG7.uNumOfBoxes == 0) return 0; nRet = L_Jp2ReadBox(hEngine,MAKE_IMAGE_PATH(TEXT("image1.jpx")),L_JPXB_MPEG7, (L_VOID**)&pMPEG7Box,0); if(nRet != SUCCESS) return nRet; *pMPEG7Data = (L_UINT8*)malloc(pMPEG7Box->uDataSize); memcpy(*pMPEG7Data, pMPEG7Box->pData,pMPEG7Box->uDataSize); *puSize = pMPEG7Box->uDataSize; /*Free the read box*/ L_Jp2FreeBoxes(hEngine, L_JPXB_MPEG7, pMPEG7Box, 1); /*Free File Info structure*/ L_Jp2FreeFileInfo(hEngine, &Jp2FileInfo); /*Destroy engine handle*/ L_Jp2Destroy(hEngine); return SUCCESS; }