写在前面的话

好像刘亦菲的妹子 哇咔咔

这周重点 优化项目中的配音合成这一块。简单分享一下ffmpeg的一些使用命令吧。

ffmpeg基本使用参考

FFmpeg开发（一）常用处理视频命令
音频工具类

//音频资源转换格式
compile 'com.github.adrielcafe:AndroidAudioConverter:0.0.8'
//简单的音频合成
compile 'com.googlecode.mp4parser:isoparser:1.1.21'

ffmpeg 处理关键帧

播放一段压缩过的视频 发现mediaplayer无法seek to到精确位置
需要处理一下关键帧
<code>

public void getNewVideo(String input_file, String output_file, ExecuteBinaryResponseHandler responseHandler) {
    try {
      Runtime.getRuntime().gc();
      String cmd = "-i " + input_file + " -c:v libx264 -preset superfast -x264opts keyint=20 -acodec copy -f mp4 " + output_file;
      Log.d("打印出的字符串是", "getNewVideo: " + cmd);
      String[] command = cmd.split(" ");
      ffmpeg.execute(command, responseHandler);
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

</code>
感觉速度有点慢 后台那边处理的话 造成文件比较打 至今没有发现什么更好的解决方案

转码

一般的转码 AndroidAudioConverter都能搞定.而且转码速度比较快
<code>

AndroidAudioConverter.with(mContext)
            .setFile(new File("XXX"))
            .setFormat(AudioFormat.AAC) //需要转码的格式
            .setCallback(new IConvertCallback() {
              @Override
              public void onSuccess(File file) {
                Log.d("转码~", "onSuccess:" + file.getPath());
              }

              @Override
              public void onFailure(Exception e) {
                Log.d("转码~", "onFailure:" + e.getMessage());
              }
            })
            .convert();

</code>

WAV 转码 AAC
<code>

public void wav2Aac(String input_file, String output_file) {
    int COMPRESSED_AUDIO_FILE_BIT_RATE = 64000; // 64kbps
    int SAMPLING_RATE = 16000;
    int BUFFER_SIZE = 48000;
    int CODEC_TIMEOUT_IN_MS = 5000;
    String COMPRESSED_AUDIO_FILE_MIME_TYPE = "audio/mp4a-latm";
    String LOGTAG = "WAV编码AAC";
    new Thread() {
      @Override
      public void run() {
        try {
          Runtime.getRuntime().gc();
          android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_BACKGROUND);
          File inputFile = new File(input_file);
          FileInputStream fis = new FileInputStream(inputFile);

          File outputFile = new File(output_file);
          if (outputFile.exists()) outputFile.delete();
          MediaMuxer mux = new MediaMuxer(outputFile.getAbsolutePath(), MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
          MediaFormat outputFormat = MediaFormat.createAudioFormat(COMPRESSED_AUDIO_FILE_MIME_TYPE, SAMPLING_RATE, 1);
          outputFormat.setInteger(MediaFormat.KEY_AAC_PROFILE, MediaCodecInfo.CodecProfileLevel.AACObjectLC);
          outputFormat.setInteger(MediaFormat.KEY_BIT_RATE, COMPRESSED_AUDIO_FILE_BIT_RATE);
          outputFormat.setInteger(MediaFormat.KEY_MAX_INPUT_SIZE, 16384);

          MediaCodec codec = MediaCodec.createEncoderByType(COMPRESSED_AUDIO_FILE_MIME_TYPE);
      codec.configure(outputFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
      codec.start();

          ByteBuffer[] codecInputBuffers = codec.getInputBuffers(); // Note: Array of buffers
          ByteBuffer[] codecOutputBuffers = codec.getOutputBuffers();

          MediaCodec.BufferInfo outBuffInfo = new MediaCodec.BufferInfo();
          byte[] tempBuffer = new byte[BUFFER_SIZE];
          boolean hasMoreData = true;
          double presentationTimeUs = 0;
          int audioTrackIdx = 0;
          int totalBytesRead = 0;
          int percentComplete = 0;
          do {
            int inputBufIndex = 0;
            while (inputBufIndex != -1 && hasMoreData) {
              inputBufIndex = codec.dequeueInputBuffer(CODEC_TIMEOUT_IN_MS);
              if (inputBufIndex >= 0) {
                ByteBuffer dstBuf = codecInputBuffers[inputBufIndex];
                dstBuf.clear();
                int bytesRead = fis.read(tempBuffer, 0, dstBuf.limit());
                Log.e("bytesRead", "Readed " + bytesRead);
                if (bytesRead == -1) { // -1 implies EOS
                  hasMoreData = false;
                  codec.queueInputBuffer(inputBufIndex, 0, 0, (long) presentationTimeUs, MediaCodec.BUFFER_FLAG_END_OF_STREAM);
                } else {
                  totalBytesRead += bytesRead;
                  dstBuf.put(tempBuffer, 0, bytesRead);
                  codec.queueInputBuffer(inputBufIndex, 0, bytesRead, (long) presentationTimeUs, 0);
                  presentationTimeUs = 1000000l * (totalBytesRead / 2) / SAMPLING_RATE;
                }
              }
            }
            // Drain audio
        int outputBufIndex = 0;
        while (outputBufIndex != MediaCodec.INFO_TRY_AGAIN_LATER) {
          outputBufIndex = codec.dequeueOutputBuffer(outBuffInfo, CODEC_TIMEOUT_IN_MS);
          if (outputBufIndex >= 0) {
            ByteBuffer encodedData = codecOutputBuffers[outputBufIndex];
            encodedData.position(outBuffInfo.offset);
            encodedData.limit(outBuffInfo.offset + outBuffInfo.size);
            if ((outBuffInfo.flags & MediaCodec.BUFFER_FLAG_CODEC_CONFIG) != 0 && outBuffInfo.size != 0) {
              codec.releaseOutputBuffer(outputBufIndex, false);
            } else {
              mux.writeSampleData(audioTrackIdx, codecOutputBuffers[outputBufIndex], outBuffInfo);
              codec.releaseOutputBuffer(outputBufIndex, false);
            }
          } else if (outputBufIndex == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
            outputFormat = codec.getOutputFormat();
            Log.v(LOGTAG, "Output format changed - " + outputFormat);
            audioTrackIdx = mux.addTrack(outputFormat);
            mux.start();
          } else if (outputBufIndex == MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED) {
            Log.e(LOGTAG, "Output buffers changed during encode!");
          } else if (outputBufIndex == MediaCodec.INFO_TRY_AGAIN_LATER) {
            // NO OP
          } else {
            Log.e(LOGTAG, "Unknown return code from dequeueOutputBuffer - " + outputBufIndex);
          }
        }
        percentComplete = (int) Math.round(((float) totalBytesRead / (float) inputFile.length()) * 100.0);
        sendMessage(onProgressing, percentComplete);
      } while (outBuffInfo.flags != MediaCodec.BUFFER_FLAG_END_OF_STREAM);
      fis.close();
      mux.stop();
      mux.release();
      Runtime.getRuntime().gc();
    } catch (FileNotFoundException e) {
      sendMessage(TransferformatError, e);
    } catch (IOException e) {
      sendMessage(TransferformatError, e);
        }
      }
    }.start();
  }

</code>
<code>

private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
  switch (msg.what) {
    case onProgressing:
      transferformatListener.onProgress(msg.arg1);
      if (msg.arg1 == 100)
        transferformatListener.Finish();
      break;
    case Finish:
      transferformatListener.Finish();
      break;
    case TransferformatError:
      transferformatListener.TransferformatError((Exception) msg.obj);
      break;
    default:
      break;
      }
    }
  };

  private final int onProgressing = 0;
  private final int Finish = 1;
  private final int TransferformatError = 2;

  private void sendMessage(int what, Object obj) {
    Message msg = mHandler.obtainMessage();
    switch (what) {
      case onProgressing:
        msg.arg1 = (int) obj;
        break;
      case TransferformatError:
        msg.obj = obj;
        break;
      default:
        break;
    }
    msg.what = what;
    mHandler.sendMessage(msg);
  }


  private TransferformatListener transferformatListener;

  public interface TransferformatListener {
    void onProgress(int progress);

    void Finish();

    void TransferformatError(Exception e);
  }

  public void setTransferformatListener(TransferformatListener listener) {
    this.transferformatListener = listener;
  }

</code>

后续会补充更多有关ffmpeg的内容

======================分割线=========================

打算这周日和家进去游泳。😀 旱鸭子 其实我是想去喝水了 。妈的= =| 家进说教我游泳 我还没反应过来就买了泳衣。我现在严重怀疑 家进是不是想去撩妹拉我壮胆。嗯 树立一个小目标 学会游泳。其实挺感谢这孙子帮我抢到一加五的 听说拍照不错 先玩玩 练手。培养兴趣 总宅着 感觉都快发霉了。不过发货很慢。。。打算周末北京各个角落游玩 有兴趣的一起。