我的创作纪念日

机缘

和大家分享最初成为创作者的初心

1. 实战项目中的经验分享
   

2. 日常学习过程中的记录
   

3. 通过文章进行技术交流
   

收获

1. 获得了7000粉丝的关注
2. 获得了很多正向的反馈，如赞、评论、阅读量
3. 认识了许多志同道合的领域同行
4. Android相关

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();
  }

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(Transferform

5、WebRTC相关

#!/bin/sh
export WORKSPACE=$(pwd)
export PATH=$WORKSPACE/depot_tools:$PATH
export http_proxy=http://192.168.6.207:20800
export https_proxy=http://192.168.6.207:20800
#cd src
#gn gen out/Debug --args='target_os="android" target_cpu="arm" is_debug=true'
#ninja -C out/Debug

#tools_webrtc/android/build_aar.py  --build-dir out --arch "armeabi-v7a" --output "libwebrtc.aar"

#tools_webrtc/android/build_aar.py --extra-gn-args='rtc_use_h264=true ffmpeg_branding="Chrome"' --build-dir out --output "libwebrtc.aar"

#tools_webrtc/android/build_aar.py --arch "armeabi-v7a" "arm64-v8a" --extra-gn-args='rtc_use_h264=true ffmpeg_branding = "Chrome"' --build-dir out --output "libwebrtc.aar"

---

日常

android开发是我的主要开发语言，也是我日常工作主要用到的，所以平时会使用的多些，也学习的深入一些。

OpenCV是一个基于Apache2.0许可（开源）发行的跨平台计算机视觉和机器学习软件库，网络上一些小伙伴写的一些关于Android版OpenCV的博客，大部分都模糊不清，基本就复制粘贴的，有些甚至没有实践就直接贴上去了，这样不仅误导初学的一些小伙伴，而且被其他小伙伴转载或者复制之后，会造成更大的影响和后果。正所谓”徒错错一个，师错错一窝。为人师者慎下笔“，故此，本专栏亲自研究，实践，将调试过程中所遭所遇进行详细讲解，注意事项进行一一列举，希望能够帮助到各位初学OpenCV的小伙伴，避免走弯路，费时费力。

MFC Windows 程序设计，因为之前在工作中主要用到，大概开发了七八年时间，现在也舍不得丢下，故而业余时间也写一些，目前写的一些，适合初学MFC的小伙伴学习研究，有对应的讲解和演示，避免走弯路，费时费力。也真心希望能够帮助正在苦学MFC Windows 程序设计的小伙伴们，你们的成长是我最大的幸福。

憧憬

希望能够凭自己的一己之力，能够帮助到各位初学开发的小伙伴，避免走弯路，费时费力，你们的成长是我最大的幸福。愿小伙伴们用心积累，避免枯燥乏味的重复。提高效率就能节约出时间，少加班，多陪陪家人。