LBitmapBase::ChangeCompression (original) (raw)
Summary
Compresses or decompresses a bitmap.
Syntax
#include "ltwrappr.h"
virtual L_INT LBitmapBase::ChangeCompression(nComp)
Parameters
L_INT nComp
Flag that indicates the type of compression to use on the bitmap. Possible values are:
| Value | Meaning |
|---|---|
| COMP_NONE | [0] No compression. This option can be used to decompress compressed or super compressed bitmaps. |
| COMP_RLE | [1] 1-bit RLE compression. This compression is very fast and Lossless. For more information, refer to Speeding Up 1-Bit Documents. This is the same as passing TYPE_COMPRESSED to LBitmapBase::Allocate. |
| COMP_SUPER | [2] Super compression. This is available for 1-bit, 8-bit, and 24-bit bitmaps only. The 24-bit and 8-bit compression is lossy, while the 1-bit compression is lossless. |
Returns
| Value | Meaning |
|---|---|
| SUCCESS | The function was successful. |
| < 1 | An error occurred. Refer to Return Codes. |
Required DLLs and Libraries
- LTDIS
- LTFIL
- LFCMP (for 24-bit Super compression)
- LFFAX (for 1-bit Super compression)
- 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
Topics
Example
L_INT LBitmapBase__ChangeCompressionExample(LBitmapBase & Bitmap, L_TCHAR * pszFile)
{
L_INT nRet;
L_TCHAR szMessage[256];
nRet =Bitmap.Load(pszFile);
if(nRet !=SUCCESS)
return nRet;
if (Bitmap.GetBitsPerPixel() == 1 || Bitmap.GetBitsPerPixel() == 24)
{
wsprintf(szMessage, TEXT("BEFORE:\nImage Size: %ld bytes\nType: %s"),
Bitmap.GetMemSize(),
Bitmap.IsSuperCompressed() ?
TEXT("Super Compressed") : TEXT("Uncompressed"));
MessageBox(NULL, szMessage, TEXT("Changing Compression"), MB_OK);
nRet = Bitmap.ChangeCompression(Bitmap.IsSuperCompressed() ?
COMP_NONE : COMP_SUPER);
if(nRet == SUCCESS)
wsprintf(szMessage,
TEXT("AFTER:\nImage Size: %ld bytes\nType: %s"),
Bitmap.GetMemSize(),
Bitmap.IsSuperCompressed() ?
TEXT("Super Compressed") : TEXT("Uncompressed"));
else
{
wsprintf(szMessage, TEXT("Change Compressions Failed!"));
return nRet;
}
MessageBox(NULL, szMessage, TEXT("Changing Compression"), MB_OK);
}
return SUCCESS;
}
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