如何在Java程序中正确调用mkvmerge？

Question

我有几百集的动漫，我想把字幕和视频文件合并成一个。我决定编写一个简短的Java程序来遍历这些文件并合并它们。视频文件名为Bleach1.mkv，字幕为Bleach1.srt。为了避免任何潜在的空格问题，这些文件保存在我的C盘的根目录下。下面是我写的代码。

根据mkvmerge的文档，适当的命令行调用是"mkvmerge -o remux_Bleach1.mkv Bleach1.mkv Bleach1.srt“。我已经确认了，这实际上是有效的。我现在从不同的文件夹运行java程序，所以我对每个文件都使用了绝对路径。

我的代码中的命令打印为"C:\Program Files\MKVToolNix\mkvmerge.exe，-o C:\Bleach\remux_Bleach_1.mkv C:\Bleach\Bleach_1.mkv C:\Bleach\Bleach_1.srt“

我从mkvmerge返回的错误消息是“错误:没有给出目标文件名”。

我不清楚在使用ProcessBuilder时参数是如何传递的--我到底做错了什么？

import org.apache.commons.io.FilenameUtils;

import java.io.*;
import java.util.ArrayList;
import java.util.List;


public class Main {

    private static String mkvmergePath = "C:\\Program Files\\MKVToolNix\\mkvmerge.exe";

    public static void mergeVideoAndSubtitles(final File folder, String videoExtension, String subtitleExtension) {
        for (final File fileEntry : folder.listFiles()) {
            if (fileEntry.isDirectory()) {
                listFilesForFolder(fileEntry, videoExtension, subtitleExtension);
                // for each mkv file that is found
            } else if (FilenameUtils.isExtension(fileEntry.getName(), videoExtension)) {
                String parentFolderPath = fileEntry.getParentFile().getPath();
                String baseName = FilenameUtils.getBaseName(fileEntry.getName());
                String outputFileAbsolutePath = parentFolderPath + "\\remux_" + fileEntry.getName();
                String inputVideoAbsolutePath = fileEntry.getAbsolutePath();
                String inputSubtitleAbsolutePath = parentFolderPath + "\\" + baseName + "." + subtitleExtension;
                String param1 = "-o " + outputFileAbsolutePath + " " + inputVideoAbsolutePath + " " + 
                        inputSubtitleAbsolutePath;
//                String param2 = "--default-track \"und\"";
//                String param3 = "--language 0:und " + baseName + "." + subtitleExtension + "\"";
//                System.out.println(param1);
//                System.out.println(param2);
//                System.out.println(param3);
                BufferedReader br = null;
                String line;
                try {
                List<String> list = new ArrayList<String>();
                list.add(mkvmergePath);
                list.add(param1);

                ProcessBuilder build = new ProcessBuilder(list);
                    System.out.println(build.command());
                                        Process process = build.start();

                    InputStream is = process.getInputStream();
                    InputStreamReader isr = new InputStreamReader(is);
                    br = new BufferedReader(isr);

                    while ((line = br.readLine()) != null) {
                        System.out.println(line);
                    }

                } catch (IOException e) {
                    e.printStackTrace();
                }


            }
        }
    }

    public static void main(String[] args) {
        final File folder = new File("C:\\Bleach");
        mergeVideoAndSubtitles(folder, "mkv", "srt");
    }
}

Answer 1

我用Go写了一个类似的程序，也遇到了同样的错误。显然，参数中的空格(例如--language 0:eng)导致了这个问题。我试着把它们分成不同的论点，看起来很管用：

public static void main(String[] args) throws IOException {
    String mkvmerge = "C:\\Program Files\\MKVToolNix\\mkvmerge.exe";

    List<String> command = new ArrayList<String>();
    command.add(mkvmerge);

    command.add("--ui-language");
    command.add("en");
    command.add("--output");
    command.add("D:\\Dump\\test.mkv");
    command.add("--language");
    command.add("0:eng");
    command.add("--default-track");
    command.add("0:yes");
    command.add("--language");
    command.add("1:eng");
    command.add("--default-track");
    command.add("1:yes");
    command.add("--language");
    command.add("2:eng");
    command.add("D:\\Dump\\Game of Thrones\\Game.of.Thrones.S01.1080p.WEB-DL.DD5.1.H.264-SA89[rartv]\\Game.of.Thrones.S01E01.Winter.Is.Coming.1080p.WEB-DL.DD5.1.H.264-SA89.mkv");
    command.add("--sub-charset");
    command.add("0:UTF-8");
    command.add("--language");
    command.add("0:eng");
    command.add("D:\\Dump\\Game of Thrones\\Game.of.Thrones.S01.1080p.WEB-DL.DD5.1.H.264-SA89[rartv]\\Subs\\Game.of.Thrones.S01E01.Winter.Is.Coming.1080p.WEB-DL.DD5.1.H.264-SA89.srt");
    command.add("--track-order");
    command.add("0:0,0:1,0:2,1:0");

    ProcessBuilder builder = new ProcessBuilder(command);
    builder.redirectErrorStream(true);
    Process process = builder.start();

    BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
    String line = null;
    while ((line = reader.readLine()) != null) {
        System.out.println(line);
    }
}

由于某些原因，这不适用于路径中的空格。这在Go中也是有效的。