Java调用linux命令ffmpeg视频转码

import java.io.*;
import java.lang.*;
import java.util.*;
import java.text.*;
import java.net.*;
public class MediocreExecJavac
{
//运行命令
public void runCmd(String command){
  try
        {           
            Runtime rt = Runtime.getRuntime();
   Process proc = rt.exec(command);
   InputStream stderr = proc.getErrorStream();
            InputStreamReader isr = new InputStreamReader(stderr);
            BufferedReader br = new BufferedReader(isr);
            String line = null;
            System.out.println("<ERROR>");
            while ( (line = br.readLine()) != null)
                System.out.println(line);
            System.out.println("</ERROR>");
            int exitVal = proc.waitFor();
            System.out.println("Process exitValue: " + exitVal);
        } catch (Throwable t)
  {
   t.printStackTrace();
  }
}

//视频转码，infile输入文件(包括完整路径)，outfile输出文件
public boolean transfer(String infile,String outfile){
  String avitoflv = "ffmpeg -i "+infile+" -ar 22050 -ab 56 -f flv -y -s 320x240 "+outfile;
  String flvto3gp = "ffmpeg -i " + infile + " -ar 8000 -ac 1 -acodec amr_nb -vcodec h263 -s 176x144 -r 12 -b 30 -ab 12 " + outfile;
  String avito3gp = "ffmpeg -i " + infile + " -ar 8000 -ac 1 -acodec amr_nb -vcodec h263 -s 176x144 -r 12 -b 30 -ab 12 " + outfile;
  //avi -> jpg
  String avitojpg = "ffmpeg -i " + infile + " -y -f image2 -ss 00:00:10 -t 00:00:01 -s 350x240 " + outfile;
  try
        {           
            Runtime rt = Runtime.getRuntime();
   Process proc = rt.exec(avitoflv);
   InputStream stderr = proc.getErrorStream();
            InputStreamReader isr = new InputStreamReader(stderr);
            BufferedReader br = new BufferedReader(isr);
            String line = null;
            System.out.println("<ERROR>");
            while ( (line = br.readLine()) != null)
                System.out.println(line);
            System.out.println("</ERROR>");
            int exitVal = proc.waitFor();
            System.out.println("Process exitValue: " + exitVal);
        } catch (Throwable t)
  {
   t.printStackTrace();
   return false;
  }
  return true;
}

//读取文件,fileName输入文件，id行数
public static String readFile(String fileName,int id)
{
  String dataStr = "";
  FileInputStream fis = null;
  try
  {
   FileReader file = new FileReader(fileName);//建立FileReader对象，并实例化为fr
   BufferedReader br=new BufferedReader(file);//建立BufferedReader对象，并实例化为br
   int i=1;
   String Line=br.readLine();//从文件读取一行字符串
   //System.out.println("Line1="+Line+"="+Line);
   //判断读取到的字符串是否不为空
   //while(Line!=null){
    //System.out.println(Line + "<br>");//输出从文件中读取的数据
    //if(i==line){dataStr=Line;break;}else{i=i+1;}
    //Line=br.readLine();//从文件中继续读取一行数据
   //}
   dataStr=Line;
   br.close();//关闭BufferedReader对象
  }
  catch(Exception e){
  }finally{
   try
   {
    if(fis!=null)
       fis.close();
   }catch(Exception e){}
  }
  return dataStr;
   }

   //读时长信息
public String readtime(String file)
{
  String str="/opt/cgogo/test/info.txt";
  String timelen = "";
  String cmd = "timelen "+file;
  runCmd(cmd);
  timelen=readFile(str,1);

  return timelen;
}

    public static void main(String args[])
    {
  MediocreExecJavac me = new MediocreExecJavac();
  String infile = "/opt/cgogo/test/02.avi";
  String outfile = "01.flv";

  //时长
  String timelen = me.readtime(infile);
  System.out.println("02.avi timelen is :" + timelen);
  //转码
  if(me.transfer(infile,outfile)){
   System.out.println("the transfer is ok!");
  }else{
   System.out.println("the transfer is error!");
  }
    }
}