mencoder转码生成文件0字节，如何解决

[pp虾我们走]

public void convertCommandAvi(String video_path){
String format = ".avi";
String newVideoPath = "F:tools/video/444"+format;
List<String> commend = new java.util.ArrayList<String>();
commend.add(MENCODER_PATH);
commend.add(video_path);
commend.add("-oac");
commend.add("mp3lame");
commend.add("-lameopts");
commend.add("preset=64");
commend.add("-ovc");
commend.add("xvid");
commend.add("-xvidencopts");
commend.add("bitrate=600");
commend.add("-of");
commend.add("avi");
commend.add("-o");
commend.add(newVideoPath);
//commend.add(videofolder + filerealname + ".avi");
// 命令类型：mencoder 1.rmvb -oac mp3lame -lameopts preset=64 -ovc xvid
// -xvidencopts bitrate=600 -of avi -o rmvb.avi

ProcessBuilder builder = new ProcessBuilder();
builder.command(commend);
try {
Process p = builder.start();
System.err.println("111111111122");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

[QWERT4745]

报的什么错，转码命令直接在cmd中执行可不可以成功转