Recherche avancée

Sur d’autres sites (4315)

• Evolution #2274 : Tri alphabétique même en présence de

  2 septembre 2011, par cedric -

  Pas de solution simple pour ce genre de question. Le problème sera le même avec un raccourci, cela faussera l’ordre. Pour ce genre de cas il vaut mieux avoir le titre brut dans le champ titre, et un champ supplémentaire pour le titre affiché qui serait ici ton abbr, et que tu n’utilises que dans ce (...)

• FFmpeg : How to split video efficiently ?

  8 mai 2017, par Antony

  I wish to split a large avi video into two smaller consecutive videos. I am using ffmpeg.

  One way is to run ffmpeg two times :

  ffmpeg -i input.avi -vcodec copy -acodec copy -ss 00:00:00 -t 00:30:00 output1.avi
  
  ffmpeg -i input.avi -vcodec copy -acodec copy -ss 00:30:00 -t 00:30:00 output2.avi

  But according to manpage of ffmpeg, I can make more than one ouput file from one input file using just one line :

  ffmpeg -i input.avi -vcodec copy -acodec copy -ss 00:00:00 -t 00:30:00 output1.avi \
  
     -vcodec copy -acodec copy -ss 00:30:00 -t 00:30:00 output2.avi

  My question is, does the later approach save computation time and memory ?

• Need to write to a file using fopen in a C++ class for iOS project

  2 mai 2014, par Chuck Mc Duran

  I have a project that uses C++ classes and FFmpeg, I need to use fopen and write a file to the app sandbox, so the code that I need to write in C++ is the equivalent of :

  NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
  
  NSString *docs_dir = [paths objectAtIndex:0];

  This would me to my app sandbox, where I can pretty much manipulate my files
  The question is how do I go about writing this code in C++ so that I can use fopen on a file ?

  This is the method that needs implementation :

  int testGrabAndWrite(const char* streamURL, bool decode, const char* filename)
  
  {
  
      FILE *outfile;
  
      int ret;
  
      int counter = 0;
  
      uint8_t *data;              // Pointer to the received audio mem
  
      int size;                   // Size of the received audio buffer
  
  
  
  
  
      outfile = fopen(filename, "w");
  
  
  
      if (outfile == NULL)
  
          exit(1);
  
  
  
      // Open the RTP stream
  
      if ((ret = openStream(streamURL, decode)) < 0)
  
          return ret;
  
  
  
      // Print out info about the stream found
  
      int tmpSampleRate, tmpBitRate, tmpChannels;
  
      ret = getStreamInfo(tmpSampleRate, tmpBitRate, tmpChannels);
  
      printf("\nSample rate:%d Bit rateL%d Channels:%d\n",tmpSampleRate,tmpBitRate, tmpChannels);
  
  
  
      // Grab some sample data and write it to file.
  
      while (counter < 500) 
  
      {
  
          ret = getStreamData(data, size);
  
          fwrite(data, 1, size, outfile);                             // Write RTP packets, i.e. mp3, to file.
  
          printf("Wrote packet %d with size %d which returned %d. ", ++counter, size, ret);
  
      }
  
  
  
      fclose(outfile);
  
      closeStream();
  
  
  
      return ret;
  
  }