ob-ivan/srt-resize.html

## srt-resize.html
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
    </head>
    <body>
        <textarea id="input"></textarea>
        <label>Offset (ms): <input id="offset"/></label>
        <label>Factor: <input id="factor"/></label>
        <button id="resize">resize</button>
        <textarea id="output"></textarea>
        <script type="text/javascript">
            function getMicroseconds(timestamp) {
                // 00:01:38,960
                var matches = new String(timestamp).match(/^(\d\d):(\d\d):(\d\d),(\d{3})$/);
                if (! matches) return null;
                var hour = parseInt(matches[1], 10);
                var min = parseInt(matches[2], 10);
                var sec = parseInt(matches[3], 10);
                var ms = parseInt(matches[4], 10);
                return ((hour * 60 + min) * 60 + sec) * 1000 + ms;
            }
            function pad(num, size) {
                var s = num + '';
                while (s.length < size) s = '0' + s;
                return s;
            }
            function makeTimestamp(microseconds) {
                var ms = microseconds % 1000;
                var input = Math.floor(microseconds / 1000);
                var sec = input % 60;
                input = Math.floor(input / 60);
                var min = input % 60;
                var hour = Math.floor(input / 60);
                return pad(hour, 2) + ':' + pad(min, 2) + ':' + pad(sec, 2) + ',' + pad(ms, 3);
            }
            function makePart(index, start, end, text) {
                return [
                    index,
                    makeTimestamp(start) + ' -' + '-> ' + makeTimestamp(end),
                    text
                ].join('\n');
            }
            document.getElementById('resize').addEventListener('click', function () {
                var input = document.getElementById('input').value.split(/\n\n/);
                var offset = parseInt(document.getElementById('offset').value, 10);
                var factor = document.getElementById('factor').value;
                var outputParts = [];
                var matches;
                for (var i = 0; i < input.length; ++i) {
                    var matches = input[i].match(/^(\d+)\n([\d:,]+) --> ([\d:,]+)\n([\s\S]+)$/);
                    if (! matches) break;
                    outputParts.push(makePart(
                        matches[1],
                        getMicroseconds(matches[2]) * factor + offset,
                        getMicroseconds(matches[3]) * factor + offset,
                        matches[4]
                    ));
                }
                document.getElementById('output').value = outputParts.join('\n\n');
            });
        </script>
    </body>
</html>
	<html>
	<head>
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
	</head>
	<body>
	<textarea id="input"></textarea>
	<label>Offset (ms): <input id="offset"/></label>
	<label>Factor: <input id="factor"/></label>
	<button id="resize">resize</button>
	<textarea id="output"></textarea>
	<script type="text/javascript">
	function getMicroseconds(timestamp) {
	// 00:01:38,960
	var matches = new String(timestamp).match(/^(\d\d):(\d\d):(\d\d),(\d{3})$/);
	if (! matches) return null;
	var hour = parseInt(matches[1], 10);
	var min = parseInt(matches[2], 10);
	var sec = parseInt(matches[3], 10);
	var ms = parseInt(matches[4], 10);
	return ((hour * 60 + min) * 60 + sec) * 1000 + ms;
	}
	function pad(num, size) {
	var s = num + '';
	while (s.length < size) s = '0' + s;
	return s;
	}
	function makeTimestamp(microseconds) {
	var ms = microseconds % 1000;
	var input = Math.floor(microseconds / 1000);
	var sec = input % 60;
	input = Math.floor(input / 60);
	var min = input % 60;
	var hour = Math.floor(input / 60);
	return pad(hour, 2) + ':' + pad(min, 2) + ':' + pad(sec, 2) + ',' + pad(ms, 3);
	}
	function makePart(index, start, end, text) {
	return [
	index,
	makeTimestamp(start) + ' -' + '-> ' + makeTimestamp(end),
	text
	].join('\n');
	}
	document.getElementById('resize').addEventListener('click', function () {
	var input = document.getElementById('input').value.split(/\n\n/);
	var offset = parseInt(document.getElementById('offset').value, 10);
	var factor = document.getElementById('factor').value;
	var outputParts = [];
	var matches;
	for (var i = 0; i < input.length; ++i) {
	var matches = input[i].match(/^(\d+)\n([\d:,]+) --> ([\d:,]+)\n([\s\S]+)$/);
	if (! matches) break;
	outputParts.push(makePart(
	matches[1],
	getMicroseconds(matches[2]) * factor + offset,
	getMicroseconds(matches[3]) * factor + offset,
	matches[4]
	));
	}
	document.getElementById('output').value = outputParts.join('\n\n');
	});
	</script>
	</body>
	</html>