From Forum Nokia Wiki

Creation of MBM file

1. Convert images to bmp and save them as .mbm using function CFbsbitmap::saveL()
2. Get this MBM filepaths into some buffer and pass them to TDesC* aSources[],
3. For TInt32 aSourceIds[] you can use ids starting from 0.
4. Call this storel() function ,mbm is ready to use now...

_LIT(KMbmFile,"C:\\result.mbm");
 
_LIT(KBMPFilePath0,"C:\\facebook.mbm");
_LIT(KBMPFilePath1,"C:\\balance.mbm");
 
TInt32* uniqueIds = new ( ELeave ) TInt32[ 2 ];
CleanupStack::PushL( uniqueIds );
uniqueIds[ 0 ] = 0;
uniqueIds[ 1 ] = 0;
 
TFileName** filenames = new ( ELeave ) TFileName*[ 2 ];
CleanupStack::PushL( filenames );
filenames[ 0 ] = new (ELeave) TFileName( KBMPFilePath0 );
filenames[ 1 ] = new (ELeave) TFileName( KBMPFilePath1 );
 
CFbsBitmap::StoreL( KMbmFile, // Filename for new multi-bitmap mbm
2, // Count of files
( const TDesC** )filenames, // bitmaps to be loaded
uniqueIds ); // id's of the bitmaps in MBM files
 
// Clean resources
delete filenames[ 0 ];
delete filenames[ 1 ];
 
CleanupStack::PopAndDestroy( filenames );
CleanupStack::PopAndDestroy( uniqueIds );

Alternate method

This method applies if you already have Bmp files and/or their masks. In this case the MBM files can be created using the mmp file.

Without mask file

START BITMAP      S60Test.mbm
HEADER
TARGETPATH        \system\apps\step6
SOURCEPATH        ..\bitmaps
SOURCE            c12  tlo.bmp
END

With mask file

START BITMAP		Myownmbm.mbm
HEADER
TARGETPATH		\system\apps\Jhalak
SOURCEPATH		..\bitmaps
SOURCE			c12 check.bmp
SOURCE			c12 check_mask.bmp
SOURCE			c12 uncheck.bmp
SOURCE			c12 uncheck_mask.bmp
END

This creates a mbg file that has to be included wherever the images need to be used. The mbg is actually a text file which contains an enum with the image indexes.

e.g.

/* This file has been generated, DO NOT MODIFY. */
enum TMbmS60test
{
EMbmS60testTlo
};