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• Making new struct point to data from old struct without old struct deleting it

  14 août 2019, par Guerlando OCs

  Here’s how I decode videos in ffmpeg :

  AVFrame* avFrame;
  
  avFrame = av_frame_alloc();
  
  int receiveFrameResult = avcodec_receive_frame(avCodecContext, avFrame);

  Now my AVFrame struct has video data in its uint8_t * data field.

  I want to create my own struct myNewStruct which holds the data that AVFrame has in uint8_t * data[].

  The problem is that I don’t want to waste CPU time by copying value by value from avFrame->data to myNewStruct->buffer.

  I also can’t simply copy the data like this :

  myNewStruct.buffer[i] = new uint8_t;
  
  myNewStruct.buffer[i] = avFrame->data[i];

  because when avFrame gets destructed, it deletes the allocated data for data. I also can’t avoid deleting avFrame because it contains other unuseful fields that I don’t want in myNewStruct.

  How should I make myNewStruct->buffer point to the same data as avFrame->data points, but without worrying if avFrame is going to delete it ?

  UPDATE :

  AVFrame is from ffmpeg so I don’t have any control of its contents, therefore I cannot make its pointers of type shared_ptr

• ERROR : "Cannot Find FFMPEG" on Google Cloud Compute Engine Debian Wheezy 7.8 Managed Instance even though it's installed

  4 octobre 2015, par DynamoBooster

  I wrote a Node.JS application that uses the fluent-ffmpeg module to watermark videos uploaded on the platform. I pushed the code to a my Google Cloud Compute Engine project, and every time I get Error : Cannot Find FFMPEG. I ssh’d into the instance once it was created and ran these commands to install FFMPEG before actually testing out the code. I am not sure what is causing the error because after this I am positive that FFMPEG is installed.

  sudo apt-get update
  
  sudo apt-get install -y ffmpeg
  
  export FFMPEG_PATH="/usr/bin/ffmpeg"
  
  export FFPROBE_PATH="/usr/bin/ffprobe"

  Below is my FFMPEG code

  function generate_thumbnail(name, path){
  
    logging.info("Generating Thumbnail");
  
    ffmpeg(path)
  
     .setFfmpegPath('/usr/bin/ffmpeg') 
  
     .setFfprobePath('/usr/bin/ffprobe')
  
     .on('end', function() {
  
          upload_thumbnail(name);
  
          logging.info("Thumbnail Generated and uploaded");
  
          return;
  
      })
  
    .on('error', function(err, stdout, stderr) {
  
          logging.info('ERROR: ' + err.message);
  
          logging.info('STDERR:' + stderr);
  
    })
  
    .on('start', function(commandLine) {
  
         logging.info(commandLine);
  
    })
  
    .screenshots({
  
      count: 1,
  
      filename: name + '_thumbnail.png',
  
      folder: 'public/images/thumbnails/'
  
    });
  
  }

• ERROR : "Cannot Find FFMPEG" on Google Cloud Compute Engine Debian Wheezy 7.8 Managed Instance even though it's installed

  17 mai 2021, par DynamoBooster

  I wrote a Node.JS application that uses the fluent-ffmpeg module to watermark videos uploaded on the platform. I pushed the code to a my Google Cloud Compute Engine project, and every time I get Error : Cannot Find FFMPEG. I ssh'd into the instance once it was created and ran these commands to install FFMPEG before actually testing out the code. I am not sure what is causing the error because after this I am positive that FFMPEG is installed.

  



  sudo apt-get update
sudo apt-get install -y ffmpeg
export FFMPEG_PATH="/usr/bin/ffmpeg"
export FFPROBE_PATH="/usr/bin/ffprobe"


  



  Below is my FFMPEG code

  



  function generate_thumbnail(name, path){
  logging.info("Generating Thumbnail");
  ffmpeg(path)
   .setFfmpegPath('/usr/bin/ffmpeg') 
   .setFfprobePath('/usr/bin/ffprobe')
   .on('end', function() {
        upload_thumbnail(name);
        logging.info("Thumbnail Generated and uploaded");
        return;
    })
  .on('error', function(err, stdout, stderr) {
        logging.info('ERROR: ' + err.message);
        logging.info('STDERR:' + stderr);
  })
  .on('start', function(commandLine) {
       logging.info(commandLine);
  })
  .screenshots({
    count: 1,
    filename: name + '_thumbnail.png',
    folder: 'public/images/thumbnails/'
  });
}