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• Revision b0c146eea9 : [svc] 1. Add two pass RC options in vp9_spatial_scalable_encoder. 2. Add r

  28 février 2014, par Minghai Shang

  Changed Paths :
   Modify /examples.mk

  
   Modify /examples/vp9_spatial_scalable_encoder.c

  
   Modify /vpx/exports_enc

  
   Modify /vpx/src/svc_encodeframe.c

  
   Modify /vpx/svc_context.h

  
  
  [svc] 1. Add two pass RC options in vp9_spatial_scalable_encoder.
  2. Add read/write for RC stats file
  The two pass RC for svc does not work yet. This is just the first
  step. We need further development to make it working.
  Change-Id : I8ef0e177dff0b5ed3c97a916beea5123717cc6f2

• Video Encoding issue

  6 octobre 2014, par pbellema

  I’m making an app that records small videos and concatenates them together (like Vine).
  If I record a video without concatenation there are no problems.
  But if I assemble recordings, two problems appear : records disappear or they are cut out.

  When I start to record :
  

   private boolean prepareVideoRecorder(){
  
      if (mCamera != null) {
  
          mMediaRecorder = new MediaRecorder();
  
  
  
          Camera.Parameters p = mCamera.getParameters();
  
  
  
          CamcorderProfile profile = CamcorderProfile.get(CamcorderProfile.QUALITY_480P);
  
  
  
          // Step 1: Unlock and set camera to MediaRecorder
  
          mCamera.unlock();
  
          mMediaRecorder.setCamera(mCamera);
  
  
  
         //mMediaRecorder.setOrientationHint(90);
  
  
  
          Log.i("MY_LOG", "set preview display");
  
  
  
  
  
          mMediaRecorder.setMaxDuration(8000);
  
  
  
          // Step 2: Set sources
  
          mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
  
          mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
  
  
  
          // Step 3: Set a CamcorderProfile (requires API Level 8 or higher)
  
          mMediaRecorder.setProfile(profile);
  
  
  
  
  
  
  
  
  
          mMediaRecorder.setVideoSize(profile.videoFrameWidth,profile.videoFrameHeight);
  
  
  
          // Step 4: Set output file
  
          mMediaRecorder.setOutputFile(getOutputMediaFile().toString());
  
  
  
          if (mFrontCamera) {
  
  
  
              mMediaRecorder.setPreviewDisplay(mFrontPreview.getHolder().getSurface());
  
          } else {
  
              mMediaRecorder.setPreviewDisplay(mBackPreview.getHolder().getSurface());
  
          }
  
  
  
          // Step 6: Prepare configured MediaRecorder
  
          try {
  
              mMediaRecorder.prepare();
  
          } catch (IllegalStateException e) {
  
              Log.d("MY_LOG", "IllegalStateException preparing MediaRecorder: " + e.getMessage());
  
              releaseMediaRecorder();
  
              return false;
  
          } catch (IOException e) {
  
              Log.d("MY_LOG", "IOException preparing MediaRecorder: " + e.getMessage());
  
              releaseMediaRecorder();
  
              return false;
  
          }
  
          return true;
  
      } else {
  
          Log.i("MY_LOG", "camera null");
  
          return false;
  
      }

  And when I stop :

  private void stopRecording(boolean forcedStop) {
  
      mRecording = false;
  
      try {
  
          mMediaRecorder.stop();
  
          releaseMediaRecorder();
  
          mCamera.lock();
  
          rotateVideo(mPaths.size() - 1, mFrontCamera);
  
         if (forcedStop) manageVideos(forcedStop);
  
      } catch (RuntimeException e) {
  
          Log.i("MY_LOG", "Exception" + e.toString());
  
      }
  
  }

  and when I finish, those are my concatenation functions :

  private void manageVideos(boolean forcedStop) {
  
      if (mPaths.size() > 1 || forcedStop) {
  
          String mediaStorageDirPath = Helper.getMediaStorageDirPath();
  
          String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
  
          final String path = mediaStorageDirPath + File.separator +
  
                  "APPEND_"+ timeStamp + ".mp4";
  
  
  
          finalVideo = path;
  
          ffmpegAppend(path);
  
      } else {
  
          finalVideo = mPaths.get(0);
  
          if (!isProcessingFFmpeg) {
  
              goToSubtitleFragment(finalVideo);
  
          }
  
      }
  
  }
  
  
  
  private void ffmpegAppend(String path) {
  
      String mediaStorageDirPath = Helper.getMediaStorageDirPath();
  
      String filePath = mediaStorageDirPath + File.separator + "append.txt";
  
  
  
      try {
  
          File f = new File(filePath);
  
  
  
          OutputStreamWriter out = new OutputStreamWriter(new FileOutputStream(f));
  
          BufferedWriter writer = new BufferedWriter(out);
  
  
  
          for (int i = 0; i < mPaths.size(); i++) {
  
              writer.write("file '" + mPaths.get(i) + "'");
  
              writer.newLine();
  
          }
  
  
  
          writer.close();
  
  
  
          String cmd = "ffmpeg -f concat -i " + filePath + " -c copy " + path;
  
  
  
          mCmd.add(cmd);
  
  
  
          manageCommands();
  
  
  
      } catch (Exception e) {
  
  
  
      }
  
  }
  
  
  
  private void manageCommands() {
  
      if (!isProcessingFFmpeg && mCmd.size() > 0) {
  
          new FFmpegTask().execute(mCmd.get(0));
  
      }
  
  }
  
  
  
  private class FFmpegTask extends AsyncTask {
  
      protected Integer doInBackground(String... cmd) {
  
          isProcessingFFmpeg = true;
  
          int fileCount = cmd.length;
  
  
  
          Processor p = new Processor(Helper.getEncodingLibraryPath(getActivity()), getActivity());
  
  
  
          for (String c : cmd) {
  
              String[] strArr = c.split(" ");
  
              p.process(strArr);
  
          }
  
  
  
          return fileCount;
  
      }
  
  
  
      protected void onProgressUpdate(Integer... progress) {
  
  
  
      }
  
  
  
      protected void onPostExecute(Integer result) {
  
          StackTraceElement[] ste = Thread.currentThread().getStackTrace();
  
          isProcessingFFmpeg = false;
  
          if (mCmd.size() > 0) {
  
              mCmd.remove(0);
  
          }
  
          if (mCmd.size() > 0) {
  
              new FFmpegTask().execute(mCmd.get(0));
  
          } else if (isFinished) {
  
              goToSubtitleFragment(finalVideo);
  
          }
  
      }
  
  }

  Do you see where the problems might be coming from ?
  Thanks to you.

• rails / streamio-ffmpeg - How to execute 2-pass encoding ?

  20 mars 2017, par R4ttlesnake

  I’m using streamio-ffmpeg to encode videos uploaded to my Rails application via ffmpeg. I want to encode the videos to .webm-format using the VP9 coding format and the VP9 Encoding Guide of the WebM Project recommends using 2-pass encoding. I managed to get the videos encoding via streamio-ffmpeg using 1-pass encoding, but I can’t figure out how to handle the 2-pass encoding.

  Here my setup so far :

  # create two tempfiles for the video and a still
  
  video = Tempfile.new(["video", ".webm"], binmode: true)
  
  still = Tempfile.new(["still", ".jpg"], binmode: true)
  
  
  
  # new FFMPEG
  
  movie = FFMPEG::Movie.new(original.path)
  
  
  
  # extract still from video
  
  movie.screenshot(still.path)
  
  
  
  # encode video
  
  options = %w(-c:v libvpx-vp9 -b:v 1000K -threads 8 -speed 4 -tile-columns 6 -frame-parallel 1 -auto-alt-ref 1 -lag-in-frames 25 -c:a libvorbis -b:a 64k -f webm)
  
  movie.transcode(video.path, options)

  The command to do a 2-pass encoding with ffmpeg would be :

  ffmpeg -i <source> -c:v libvpx-vp9 -pass 1 ... -f webm /dev/null
  
  ffmpeg -i <source> -c:v libvpx-vp9 -pass 2 ... -f output.webm
  
  </source></source>

  In particular, I don’t get how to pass the file of the first encoding step to the second step with streamio-ffmpeg. How would I apply these two steps to the syntax of movie.transcode(output, options) ?

  Thanks !