LFile::Compact

#include "ltwrappr.h"

L_INT LFile::Compact(pszDstFile, uPages, pLoadFileOption, pSaveFileOption)

Compacts TIFF / BigTIFF files. It can also be used to copy or extract one or more pages from a TIFF / BigTIFF file and copy them without recompression to another TIFF / BigTIFF file.

Returns

Comments

This function can also be used to convert a TIFF file to BigTIFF and vice versa (BigTIFF -> TIFF).

The following members of the LOADFILEOPTION structure are important for this function:

• PageNumber: specifies the start page. Page 0 is the first page, page 1 is the second page, etc. The pages will be read starting with this page.

• Flags: specifies whether to use the IFD.

• IFD: used only if Flags contains the ELO_USEIFD flag. If ELO_USEIFD is not set, the PageNumber references the beginning of the file.

• (32-bit only) IFD64: used only if Flags2 contains the ELO2_USEIFD64. If ELO_USEIFD64 is not set, the PageNumber references the beginning of the file.

If pSaveFileOption is NULL, then if pszDstFile exists, it will be overwritten regardless of its format. Also, defaults will be used when saving the file (it will be saved in Intel format). Refer to the SAVEFILEOPTION documentation. TIF files are saved in two possible byte orders: Intel or Motorola (see SAVEFILEOPTIONS.Flags and ESO_MOTOROLAORDER flag.

If pSaveFileOption is not NULL, the following members of the SAVEFILEOPTION structure are important for this function:

• PageNumber: specifies the start page. This parameter is used as follows:

  • If ESO_INSERTPAGE is set in Flags, all the pages are inserted before this page.

  • If ESO_REPLACEPAGE is set in Flags, this page and the remaining uPages 1 will be replaced.

• If none of the above parameters are set, then:

  • If PageNumber is 0, the file will be overwritten.

  • If PageNumber is <> 0, the pages will be appended to the end of the file.

• IFD: can be used to speed up file access for TIFF files having many pages. Used only if ESO_USEIFD is set in Flags.

• (32-bit only) IFD64: can be used to speed up file access for TIFF files having many pages. Used only if ESO2_USEIFD64 is set in Flags.

Flags: can be used to specify one or more options:

• ESO_NOSUBFILETYPE if this flag is set, then the TGSUBFILETYPE tag will be stripped from all the pages.

• ESO_REPLACEPAGE if this is set, pages in pszDstFile are replaced starting with page PageNumber.

• ESO_INSERTPAGE - if this is set, all the pages are inserted before page PageNumber.

• ESO_USEIFD if this is set, the first page in pszDstFile is at offset IFD. All pages will be relative to that page. (Note that this might not be the first physical page in the file). This is a common technique for manipulating files with thousands of pages.

• ESO_MOTOROLAORDER if this is set and you are creating a new file, the pages will be saved in Motorola byte order. If the flag is not set, the pages will be saved in Inter byte order. If you are modifying an existing file, this flag has no meaning the pages will be saved in the same byte order used in the file.

Flags2: Can be used to specify one or more of the following options:

• ESO2_BIGTIFF: if set, the destination file will be BigTIFF instead of regular TIFF. BigTIFF files are similar to TIFF files, but are somewhat non-standard and not supported by all readers. But BigTIFF files use 64-bit file offsets so they can be greater than 4GB.

• (32-bit only) If ESO2_USEIFD64 is set, then the first page in pszDstFile is at offset IFD64. All pages are relative to that page. Useful only with BigTIFF files.

IFD64 offsets are useful only when processing BigTIFF files in 32-bit applications. For such files, the IFD pointer can be a 64-bit value > 0xFFFFFFFF. Because IFD is already a 64-bit value in 64-bit applications, IFD64 is not defined in 64-bit applications. In addition, regular TIFF files cannot use 64-bit pointers, so it is not necessary to use IFD64 with TIFF files.

Required DLLs and Libraries

Platforms

Win32, x64.

// Example 1 
L_INT LFile__CompactExample_1()  
{ 
   /* This example will compact all the pages in a TIFF file. */ 
   /* It will create a new file called dstfile.tif */ 
 
   LFile File; 
   L_INT nRet = 0 ; 
 
   File.SetFileName(MAKE_IMAGE_PATH(TEXT("clean.tif"))) ; 
 
   nRet = File.Compact(MAKE_IMAGE_PATH(TEXT("dstfile.tif")), 0, NULL, NULL);  
 
   if(nRet != SUCCESS)  
   { 
      MessageBox(NULL, TEXT("Error compacting file!"), TEXT("ERROR"), MB_OK); 
 
      return nRet; 
   } 
 
   return SUCCESS; 
} 
 
// Example 2 
L_INT LFile__CompactExample_2()  
{ 
   /* This example will compact all the pages in a TIFF file.*/ 
   /* It will append all the pages to an existing file called dstfile.tif */ 
   LFile File; 
   SAVEFILEOPTION SaveFileOption; 
   L_INT nRet = 0 ; 
 
   File.SetFileName(MAKE_IMAGE_PATH(TEXT("clean.tif"))) ; 
 
   File.GetDefaultSaveFileOption(&SaveFileOption, sizeof(SaveFileOption)); 
   SaveFileOption.PageNumber = 2; 
 
   nRet = File.Compact(MAKE_IMAGE_PATH(TEXT("dstfile.tif")), 0, NULL, &SaveFileOption); 
   if(nRet != SUCCESS) 
   { 
      MessageBox(NULL, TEXT("Error compacting file!"), TEXT("ERROR"), MB_OK); 
 
      return nRet; 
   } 
 
   return SUCCESS; 
}