音视频编码转换-ffmpeg

1.前言
    由于最近在做ios与android端需要做amr至mp3的转换，在网上搜了下资料，基本都是用ffmpeg做音视频类转换
2.ffmpeg下载安装
    2.1、下载ffmpeg。
    下载网址：http://www.ffmpeg.org/download.html
   
    2.2、解压缩

    tar -zxvf ffmpeg-2.0.1.tar.gz

   
   2.3、编辑profile文件：
          vi /etc/profile
        在文件末尾加上两句话：

        export FFMPEG_HOME=/usr/local/ffmpeg 
        export PATH=$FFMPEG_HOME/bin:$PATH

    2.4、配置安装路径之类的：

    ./configure --enable-shared --prefix=/usr/local/ffmpeg
    --enable-shared 参数据说是允许其编译产生动态库，在以后的编程中要用到这个几个动态库，我也没考证，就直接用了。
   如果出现异常，提示因为缺少yasm，需要添加参数，再执行以下命令：
    ./configure --enable-shared --disable-yasm --prefix=/usr/local/ffmpeg
    如果执行结果不对，可以根据提示信息，并查看帮助，解决问题
    ./configure --help

    2.5、编译安装

    make
    make install

    2.6、安装之后在/usr/local/ffmpeg会看到有三个目录

    bin 执行文件目录
    lib 静态，动态链接库目录
    include 编程用到的头文件

    2.7、为了防止执行程序找不到库文件，

    可以将/usr/local/ffmpeg/lib目录设置到LD_LIBRARY_PATH环境变量

    8、若出现error while loading shared libraries: libavdevice.so.52的错误

    修改/etc/ld.so.conf 在最后一行加上/usr/local/ffmpeg/lib
    ldconfig -v
    并修改 /usr/local/ffmpeg/lib目录下的文件权限为777

3.shell脚本命令转换

./ffmpeg -i source.amr dest.mp3

4.ffmpeg自带转换

/**
 * useFfmpegToMp3
 *
 * @param ffmpeg
 * @param source
 * @param target
 */
public static void useFfmpegToMp3(String ffmpeg, String source, String target){
    Runtime run = null;
    try {
        long start=System.currentTimeMillis();
        run = Runtime.getRuntime();
        //设置文件运行权限
        run.exec(new String[] { "/bin/chmod", "755", ffmpeg});
        String runCmd = ffmpeg + " -i " + source + " " +  target;
        //运行命令
        Process proc = run.exec(runCmd);
        proc.getOutputStream().flush();
        proc.getOutputStream().close();
        proc.getInputStream().close();
        LOGGER.info("Dest File Size:{}", new File(target).length());
        long end=System.currentTimeMillis();
        LOGGER.info("useFfmpegToMp3 Complete:{} -> {}, cost ms:{}", source, target, end-start);
    } catch (Exception e) {
        LOGGER.error("useJaveToMp3 Exception: ", e);
    } finally{
        //run调用lame解码器最后释放内存
        run.freeMemory();
    }
}

5.Jave转换

下载地址:http://www.sauronsoftware.it/projects/jave/download.php

 
/**
 * jave 转换mp3
 *
 * @param source
 * @param target
 */
public static void useJaveToMp3(String source, String target) {

    try {
        long start=System.currentTimeMillis();
        File sourceFile = new File(source);
        File targetFile = new File(target);
        AudioAttributes audio = new AudioAttributes();
        Encoder encoder = new Encoder();
        audio.setCodec("libmp3lame");
        EncodingAttributes attrs = new EncodingAttributes();
        attrs.setFormat("mp3");
        attrs.setAudioAttributes(audio);
        encoder.encode(sourceFile, targetFile, attrs);
        LOGGER.info("Dest File Size:{}", targetFile.length());
        long end=System.currentTimeMillis();
        LOGGER.info("useJaveToMp3 Complete:{} -> {}, cost ms:{}", source, target, end-start);
    }catch (Exceptio){
        LOGGER.error("useJaveToMp3 Exception: ", e);
    }

}

备注:
如果自带的FFmpeg转码报错，编译最新的ffmpeg，执行就可以了
官方示例：

 //From a generic AVI to a youtube-like FLV movie, with an embedded MP3 audio stream:

 File source = new File("source.avi");
 File target = new File("target.flv");
 AudioAttributes audio = new AudioAttributes();
 audio.setCodec("libmp3lame");
 audio.setBitRate(new Integer(64000));
 audio.setChannels(new Integer(1));
 audio.setSamplingRate(new Integer(22050));
 VideoAttributes video = new VideoAttributes();
 video.setCodec("flv");
 video.setBitRate(new Integer(160000));
 video.setFrameRate(new Integer(15));
 video.setSize(new VideoSize(400, 300));
 EncodingAttributes attrs = new EncodingAttributes();
 attrs.setFormat("flv");
 attrs.setAudioAttributes(audio);
 attrs.setVideoAttributes(video);
 Encoder encoder = new Encoder();
 encoder.encode(source, target, attrs);
 
 //Next lines extracts audio informations from an AVI and store them in a plain WAV file:

 File source = new File("source.avi");
 File target = new File("target.wav");
 AudioAttributes audio = new AudioAttributes();
 audio.setCodec("pcm_s16le");
 EncodingAttributes attrs = new EncodingAttributes();
 attrs.setFormat("wav");
 attrs.setAudioAttributes(audio);
 Encoder encoder = new Encoder();
 encoder.encode(source, target, attrs);
// Next example takes an audio WAV file and generates a 128 kbit/s, stereo, 44100 Hz MP3 file:

 File source = new File("source.wav");
 File target = new File("target.mp3");
 AudioAttributes audio = new AudioAttributes();
 audio.setCodec("libmp3lame");
 audio.setBitRate(new Integer(128000));
 audio.setChannels(new Integer(2));
 audio.setSamplingRate(new Integer(44100));
 EncodingAttributes attrs = new EncodingAttributes();
 attrs.setFormat("mp3");
 attrs.setAudioAttributes(audio);
 Encoder encoder = new Encoder();
 encoder.encode(source, target, attrs);
// Next one decodes a generic AVI file and creates another one with the same video stream of the source and a re-encoded low quality MP3 audio stream:

 File source = new File("source.avi");
 File target = new File("target.avi");
 AudioAttributes audio = new AudioAttributes();
 audio.setCodec("libmp3lame");
 audio.setBitRate(new Integer(56000));
 audio.setChannels(new Integer(1));
 audio.setSamplingRate(new Integer(22050));
 VideoAttributes video = new VideoAttributes();
 video.setCodec(VideoAttributes.DIRECT_STREAM_COPY);
 EncodingAttributes attrs = new EncodingAttributes();
 attrs.setFormat("avi");
 attrs.setAudioAttributes(audio);
 attrs.setVideoAttributes(video);
 Encoder encoder = new Encoder();
 encoder.encode(source, target, attrs);
 //Next one generates an AVI with MPEG 4/DivX video and OGG Vorbis audio:

 File source = new File("source.avi");
 File target = new File("target.avi");
 AudioAttributes audio = new AudioAttributes();
 audio.setCodec("libvorbis");
 VideoAttributes video = new VideoAttributes();
 video.setCodec("mpeg4");
 video.setTag("DIVX");
 video.setBitRate(new Integer(160000));
 video.setFrameRate(new Integer(30));
 EncodingAttributes attrs = new EncodingAttributes();
 attrs.setFormat("mpegvideo");
 attrs.setAudioAttributes(audio);
 attrs.setVideoAttributes(video);
 Encoder encoder = new Encoder();
 encoder.encode(source, target, attrs);
// A smartphone suitable video:

 File source = new File("source.avi");
 File target = new File("target.3gp");
 AudioAttributes audio = new AudioAttributes();
 audio.setCodec("libfaac");
 audio.setBitRate(new Integer(128000));
 audio.setSamplingRate(new Integer(44100));
 audio.setChannels(new Integer(2));
 VideoAttributes video = new VideoAttributes();
 video.setCodec("mpeg4");
 video.setBitRate(new Integer(160000));
 video.setFrameRate(new Integer(15));
 video.setSize(new VideoSize(176, 144));
 EncodingAttributes attrs = new EncodingAttributes();
 attrs.setFormat("3gp");
 attrs.setAudioAttributes(audio);
 attrs.setVideoAttributes(video);
 Encoder encoder = new Encoder();
 encoder.encode(source, target, attrs);