一个修改电影字幕时间偏移的小程序

今天晚上看电影的时候在射手网上下载了一个字幕文件，看了一会儿就发觉字幕有点跟不上电影，差了两三秒钟吧，我想这应该是大家都遇到过的问题。怎么办呢，既然咱是程序员，那就动动手，发挥一下，于是花了20分钟写了这么个小程序，很简陋，但是记录下来，一方面为了做个记录，另一方面也为了能够帮到别人，如果你也有同样的需求，希望能节省一点你的时间吧

附上jar文件，使用方法 java -jar SrtTimelineChanger 字幕文件路径 调节的时间（以毫秒计算） 如： java -jar SrtTimelineChanger 1.srt -3000

只适用于.srt文件，或是时间方式为 HH:MM:SS,nnn ---> HH:MM:SS,nnn的字幕文件，编码为gbk

代码如下：

/*
 * Copyright 2013
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.yueang.tools;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;

public class SrtTimelineChanger {

    public static void main(String[] args) {

        if (args.length != 2) {
            System.out.print("params wrong");
            return;
        }

        String filePath = args[0];
        int timeShift = Integer.parseInt(args[1]);

        SrtTimelineChanger changer = new SrtTimelineChanger();
        try {
            changer.change(filePath, timeShift);
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        System.out.print("Exit");
    }

    private void change(String filePath, int timeShift) throws IOException {
        File file = new File(filePath);

        StringBuilder sb = new StringBuilder();
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                new FileInputStream(file), "gbk"));
        String line = reader.readLine();
        while (line != null) {
            sb.append(changeLine(line, timeShift));
            sb.append("\r\n");
            line = reader.readLine();
        }

        reader.close();
        File outFile = new File(filePath + ".out");
        if (outFile.exists()) {
            outFile.delete();
        }
        outFile.createNewFile();
        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(
                new FileOutputStream(outFile), "gbk"));
        writer.write(sb.toString());
        writer.flush();
        writer.close();
    }

    private Object changeLine(String line, int timeShift) {
        if (line.matches("^\\d\\d:\\d\\d:\\d\\d,\\d\\d\\d.*\\d\\d:\\d\\d:\\d\\d,\\d\\d\\d$")) {
            int start = calculate(line.substring(0, 12));
            int end = calculate(line.substring(17, 29));

            StringBuilder sb = new StringBuilder();
            sb.append(expand(start + timeShift));
            sb.append(" --> ");
            sb.append(expand(end + timeShift));

            System.out.println(line);
            System.out.println(sb.toString());

            return sb.toString();
        }

        return line;
    }

    private String expand(long l) {
        int hour = (int) (l / 3600000);
        int min = (int) ((l - hour * 3600000) / 60000);
        int sec = (int) ((l - hour * 3600000 - min * 60000) / 1000);
        int mili = (int) (l - hour * 3600000 - min * 60000 - sec * 1000);

        return String.format("%02d:%02d:%02d,%03d", hour, min, sec, mili);
    }

    private int calculate(String time) {
        int hour = Integer.parseInt(time.substring(0, 2));
        int min = Integer.parseInt(time.substring(3, 5));
        int sec = Integer.parseInt(time.substring(6, 8));
        int mili = Integer.parseInt(time.substring(9, 12));

        return mili + sec * 1000 + min * 60000 + hour * 3600000;
    }
}