javascript: photoshop save for web with metadata

gistfile1

function Cs4SFW(FileName,Quality,MetaData, Profile,Progressive) {
  function cTID(s) { return app.charIDToTypeID(s); };
  function sTID(s) { return app.stringIDToTypeID(s); };
  /*
  reference	-> http://forums.adobe.com/message/2582725
  Metadata:-
 'MDAl'  All metadata 'MDNn'  No metadata
 'MDCp'  Copywright  'MDCC' Copyright and contact
 'MDAx'  All except camera info
 Profile:-
 'CHsR' sRGB Profile    'CHDc'  Use document profile
  */
	//Set defaults
	if(MetaData == undefined) MetaData = 'MDNn';
	if(Quality == undefined) Quality = 60;
	if(Profile == undefined) Profile = 'CHsR';	
	if(Progressive == undefined) Progressive = 1;
	    var desc7 = new ActionDescriptor();
	        var desc8 = new ActionDescriptor();
	        desc8.putEnumerated( cTID('Op  '), cTID('SWOp'), cTID('OpSa') );
	        desc8.putEnumerated( cTID('Fmt '), cTID('IRFm'), cTID('JPEG') );
	        desc8.putBoolean( cTID('Intr'), false );
	        desc8.putInteger( cTID('Qlty'), Quality );
	        desc8.putInteger( cTID('QChS'), 0 );
	        desc8.putInteger( cTID('QCUI'), 0 );
	        desc8.putBoolean( cTID('QChT'), false );
	        desc8.putBoolean( cTID('QChV'), false );
	        desc8.putBoolean( cTID('Optm'), true );
	        desc8.putInteger( cTID('Pass'), Progressive ); // 1 = Optimized 3 = Progressive
	        desc8.putDouble( cTID('blur'), 0.000000 );
	        desc8.putBoolean( cTID('EICC'), false ); //Embed Color Profile, Bool
	        desc8.putBoolean( cTID('Mtt '), false );
	        desc8.putInteger( cTID('MttR'), 255 );
	        desc8.putInteger( cTID('MttG'), 255 );
	        desc8.putInteger( cTID('MttB'), 255 );
	        desc8.putBoolean( cTID('SHTM'), false );
	        desc8.putBoolean( cTID('SImg'), true );
	        desc8.putEnumerated( cTID('SWch'), cTID('STch'), cTID(Profile) );
	        desc8.putEnumerated( cTID('SWmd'), cTID('STmd'), cTID(MetaData) );
	        desc8.putBoolean( cTID('SSSO'), false );
	            var list2 = new ActionList();
	        desc8.putList( cTID('SSLt'), list2 );
	        desc8.putBoolean( cTID('DIDr'), false );
	        desc8.putPath( cTID('In  '), new File( FileName) );
	    desc7.putObject( cTID('Usng'), sTID('SaveForWeb'), desc8 );
	    executeAction( cTID('Expr'), desc7, DialogModes.NO );
};