Count timecode starting base on in Point of the layer. Text Source

inPointTimecode.jsx

rate = 1;
clockStart = 0;
function addZero( n ) {
	if (n<10){
		return "0"+n
	}
	else {
		return ""+n
	}
}
clockTime = clockStart + rate * ( time - inPoint );

t = Math.floor( clockTime );
hours = Math.floor( t/3600 );
min = Math.floor( ( t%3600 )/ 60 );
sec=Math.floor( t%60 );
addZero( hours ) + ":" + addZero( min ) + ":" + addZero( sec );