如何以字节块播放视频？

Posted 2023-02-25

【中文标题】如何以字节块播放视频？

【英文标题】：How can i play a video in chunks of bytes?

【发布时间】：2014-02-04 06:05:14

【问题描述】：

我想在我保存在我的资产文件夹中的 android 中播放视频。 我已将其更改为字节数组，并且播放成功，使用以下代码

private String getDataSource() throws IOException 

    InputStream stream = getAssets().open("famous.3gp");

              if (stream == null)
        throw new RuntimeException("stream is null");

                File temp = File.createTempFile("test", "mp4");

       temp.deleteOnExit();

               String tempPath = temp.getAbsolutePath();

    int totalRead = 0;
    int bytesToRead = 1 * 1024;
    FileOutputStream out = new FileOutputStream(temp);
    byte buf[] = new byte[128];
    int numread = 0;

            do 
        numread = stream.read(buf);
        totalRead += numread;
        if (numread <= 0)
            break;
        out.write(buf, 0, numread);
     while (totalRead<bytesToRead);

        try 
        stream.close();
       catch (IOException ex) 
        Log.e("mini", "error: " + ex.getMessage(), ex);
      

        return tempPath;

         // 

     

在oncreate中

 videoView.setVideoPath(getDataSource());

但我的要求是，我想播放数组中的前 100 个字节，完成后，依次播放接下来的 100 个字节，然后再播放 100 个这样的字节。

【参考方案1】：

我找到了解决办法

public class VideoDemo extends Activity 

private MediaController ctlr;


VideoView videoView = null;

Context context = null;
long totalRead = 0;
int bytesToRead = 50 * 1024;

private int mPlayerPosition;
private File mBufferFile;

@Override
public void onCreate(Bundle icicle) 
    super.onCreate(icicle);
    getWindow().setFormat(PixelFormat.TRANSLUCENT);
    setContentView(R.layout.main);




    videoView = (VideoView) findViewById(R.id.videoview);


    ctlr = new MediaController(this);

    ctlr.setMediaPlayer(videoView);
    videoView.setMediaController(ctlr);
    videoView.requestFocus();

    new GetYoutubeFile().start();






private class GetYoutubeFile extends Thread 
    private String mUrl;
    private String mFile;

    public GetYoutubeFile() 

    

    @Override
    public void run() 
        super.run();
        try 

            File bufferingDir = new File(
                    Environment.getExternalStorageDirectory()
                            + "/YoutubeBuff");
            InputStream stream = getAssets().open("famous.3gp");
            if (stream == null)
                throw new RuntimeException("stream is null");
            File temp = File.createTempFile("test", "mp4");
            System.out.println("hi");
            temp.deleteOnExit();
            String tempPath = temp.getAbsolutePath();

            File bufferFile = File.createTempFile("test", "mp4");

            BufferedOutputStream bufferOS = new BufferedOutputStream(
                    new FileOutputStream(bufferFile));


            InputStream is = getAssets().open("famous.3gp");
            BufferedInputStream bis = new BufferedInputStream(is, 2048);

            byte[] buffer = new byte[16384];
            int numRead;
            boolean started = false;
            while ((numRead = bis.read(buffer)) != -1) 

                bufferOS.write(buffer, 0, numRead);
                bufferOS.flush();
                totalRead += numRead;
                if (totalRead > 120000 && !started) 
                    Log.e("Player", "BufferHIT:StartPlay");
                    setSourceAndStartPlay(bufferFile);
                    started = true;
                

            
            mBufferFile = bufferFile;

         catch (MalformedURLException e) 
            e.printStackTrace();
         catch (IOException e) 
            e.printStackTrace();
        
    


public void setSourceAndStartPlay(File bufferFile) 
    try 

        mPlayerPosition=videoView.getCurrentPosition();
        videoView.setVideoPath(bufferFile.getAbsolutePath());

        videoView.start();

     catch (IllegalArgumentException e) 
        e.printStackTrace();
     catch (IllegalStateException e) 
        e.printStackTrace();
     catch (Exception e) 
        e.printStackTrace();
    


public void onCompletion(MediaPlayer mp) 
    mPlayerPosition = mp.getCurrentPosition();
    try 
        mp.reset();
        videoView.setVideoPath(new File("mnt/sdcard/YoutubeBuff/"
                + mBufferFile).getAbsolutePath());
        mp.seekTo(mPlayerPosition);
        videoView.start();
     catch (IllegalArgumentException e) 
        e.printStackTrace();
     catch (IllegalStateException e) 
        e.printStackTrace();
     catch (Exception e) 
        e.printStackTrace();
    

在我的 xml 中，我只有 videoview

【讨论】：

很好的解决方案

嗨@MeenalSharma 我正在尝试做与您在这里所做的相同的事情，但我没有使用本地文件，而是使用来自网络的字节块......但是它不起作用...当我运行 videoView.start() 时，我的视频视图显示“无法播放视频”...您能帮帮我吗？

@jguilhermeam 可能你得到的视频格式不正确或者接收到的数据会有一些错误..

是的@MeenalSharma 我发现了一种适用于流媒体的格式。但在 seekTo() 部分，视频看起来并不流畅。现在我正在寻找其他解决方案

@Kanchan 经过大量探索后，我发现做到这一点并使视频看起来流畅的唯一方法是使用 RTP 流。在android中你可以使用这个库github.com/fyhertz/libstreaming