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• Anomalie #1964 : Le compilateur mange les ancres #Map

  26 mai 2013, par cedric -

  ah la limite de 3 caractères mini a du disparaitre un jour car je n’en ai pas trouvé trace

• php stream any mp4

  3 avril 2012, par GRaecuS

  I'm developing a web app that converts videos and allows to play them through Flowplayer.

  On the current status, I use ffmpeg to convert the videos to mp4 and qtfaststart to fix their metadata for streaming. Everything is working smoothly as I can download any converted mp4 and view it correctly.

  For serving the videos to Flowplayer, I use a php file which contains the following (summarized) code :

  header("Content-Type: {$mediatype}");
  
  
  
  if ( empty($_SERVER['HTTP_RANGE']) )
  
  {
  
      if ( $filetype == 'flv' && $seekPos != 0 )
  
      {
  
          header("Content-Length: " . ($filesize + 13));
  
          print('FLV');
  
          print(pack('C', 1));
  
          print(pack('C', 1));
  
          print(pack('N', 9));
  
          print(pack('N', 9));
  
      }
  
      else
  
      {           
  
          header("Content-Length: {$filesize}");
  
      }
  
  
  
      $fh = fopen($filepath, "rb") or die("Could not open file: {$filepath}");
  
  
  
      # seek to requested file position
  
      fseek($fh, $seekPos);
  
  
  
      # output file
  
      while(!feof($fh))
  
      {
  
          # output file without bandwidth limiting
  
          echo fread($fh, $filesize);
  
      }
  
      fclose($fh);
  
  }
  
  else //violes rfc2616, which requires ignoring  the header if it's invalid
  
  {   
  
      $fp = @fopen($file, 'rb');
  
  
  
      $size   = filesize($file); // File size
  
      $length = $size;           // Content length
  
      $start  = 0;               // Start byte
  
      $end    = $size - 1;       // End byte
  
      // Now that we've gotten so far without errors we send the accept range header
  
      /* At the moment we only support single ranges.
  
       * Multiple ranges requires some more work to ensure it works correctly
  
       * and comply with the spesifications: http://www.w3.org/Protocols/rfc2616/rfc2616-sec19.html#sec19.2
  
       *
  
       * Multirange support annouces itself with:
  
       * header('Accept-Ranges: bytes');
  
       *
  
       * Multirange content must be sent with multipart/byteranges mediatype,
  
       * (mediatype = mimetype)
  
       * as well as a boundry header to indicate the various chunks of data.
  
       */
  
      header("Accept-Ranges: 0-$length");
  
      // header('Accept-Ranges: bytes');
  
      // multipart/byteranges
  
      // http://www.w3.org/Protocols/rfc2616/rfc2616-sec19.html#sec19.2
  
      if (isset($_SERVER['HTTP_RANGE']))
  
      {
  
          $c_start = $start;
  
          $c_end   = $end;
  
          // Extract the range string
  
          list(, $range) = explode('=', $_SERVER['HTTP_RANGE'], 2);
  
          // Make sure the client hasn't sent us a multibyte range
  
          if (strpos($range, ',') !== false)
  
          {
  
              // (?) Shoud this be issued here, or should the first
  
              // range be used? Or should the header be ignored and
  
              // we output the whole content?
  
              header('HTTP/1.1 416 Requested Range Not Satisfiable');
  
              header("Content-Range: bytes $start-$end/$size");
  
              // (?) Echo some info to the client?
  
              exit;
  
          }
  
          // If the range starts with an '-' we start from the beginning
  
          // If not, we forward the file pointer
  
          // And make sure to get the end byte if spesified
  
          if ($range0 == '-')
  
          {
  
  
  
              // The n-number of the last bytes is requested
  
              $c_start = $size - substr($range, 1);
  
          }
  
          else
  
          {
  
              $range  = explode('-', $range);
  
              $c_start = $range[0];
  
              $c_end   = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $size;
  
          }
  
          /* Check the range and make sure it's treated according to the specs.
  
           * http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
  
           */
  
          // End bytes can not be larger than $end.
  
          $c_end = ($c_end > $end) ? $end : $c_end;
  
          // Validate the requested range and return an error if it's not correct.
  
          if ($c_start > $c_end || $c_start > $size - 1 || $c_end >= $size)
  
          {
  
              header('HTTP/1.1 416 Requested Range Not Satisfiable');
  
              header("Content-Range: bytes $start-$end/$size");
  
              // (?) Echo some info to the client?
  
              exit;
  
          }
  
          $start  = $c_start;
  
          $end    = $c_end;
  
          $length = $end - $start + 1; // Calculate new content length
  
          fseek($fp, $start);
  
          header('HTTP/1.1 206 Partial Content');
  
      }
  
  
  
      // Notify the client the byte range we'll be outputting
  
      header("Content-Range: bytes $start-$end/$size");
  
      header("Content-Length: $length");
  
  
  
      // Start buffered download
  
      $buffer = 1024 * 8;
  
      while(!feof($fp) && ($p = ftell($fp)) <= $end)
  
      {
  
          if ($p + $buffer > $end)
  
          {
  
              // In case we're only outputtin a chunk, make sure we don't
  
              // read past the length
  
              $buffer = $end - $p + 1;
  
          }
  
          set_time_limit(0); // Reset time limit for big files
  
          echo fread($fp, $buffer);
  
          flush(); // Free up memory. Otherwise large files will trigger PHP's memory limit.
  
      }
  
  
  
      fclose($fp);
  
  }

  Unfortunately, it is working only for the majority of the videos. For some of them, Flowplayer keeps returning Error 200, even though they were encoded correctly.

  How can I fix this ? Is it a coding problem or those videos are faulty ?

• Revisiting Nosefart and Discovering GME

  30 mai 2011, par Multimedia Mike — Game Hacking

  I found the following screenshot buried deep in an old directory structure of mine :

  
  
  

  I tried to recall how this screenshot came to exist. Had I actually created a functional KDE frontend to Nosefart yet neglected to release it ? I think it’s more likely that I used some designer tool (possibly KDevelop) to prototype a frontend. This would have been sometime in 2000.

  However, this screenshot prompted me to revisit Nosefart.

  Nosefart Background
  Nosefart is a program that can play Nintendo Sound Format (NSF) files. NSF files are files containing components that were surgically separated from Nintendo Entertainment System (NES) ROM dumps. These components contain the music playback engines for various games. An NSF player is a stripped down emulation system that can simulate the NES6502 CPU along with the custom hardware (2 square waves, 1 triangle wave, 1 noise generator, and 1 limited digital channel).

  Nosefart was written by Matt Conte and eventually imported into a Sourceforge project, though it has not seen any development since then. The distribution contains standalone command line players for Linux and DOS, a GTK frontend for the Linux command line version, and plugins for Winamp, XMMS, and CL-Amp.

  The Sourceforge project page notes that Nosefart is also part of XBMC. Let the record show that Nosefart is also incorporated into xine (I did that in 2002, I think).

  Upgrading the API
  When I tried running the command line version of Nosefart under Linux, I hit hard against the legacy audio API : OSS. Remember that ?

  In fairly short order, I was able to upgrade the CL program to use PulseAudio. The program is not especially sophisticated. It’s a single-threaded affair which checks for a keypress, processes an audio frame, and sends the frame out to the OSS file interface. All that was needed was to rewrite open_hardware() and close_hardware() for PA and then replace the write statement in play(). The only quirk that stood out is that including <pulse/pulseaudio.h> is insufficient for programming PA’s simple API. <pulse/simple.h> must be included separately.

  For extra credit, I adapted the program to ALSA. The program uses the most simplistic audio output API possible — just keep filling a buffer and sending it out to the DAC.

  Discovering GME
  I’m not sure what to do with the the program now since, during my research to attempt to bring Nosefart up to date, I became aware of a software library named Game Music Emu, or GME. It’s a pure C++ library that can essentially play any classic video game format you can possible name. Wow. A lot can happen in 10 years when you’re not paying attention.

  It’s such a well-written library that I didn’t need any tutorial or documentation to come up to speed. Just a quick read of the main gme.h header library enabled me in short order to whip up a quick C program that could play NSF and SPC files. Path of least resistance : Client program asks library to open a hardcoded file, synthesize 10 seconds of audio, and dump it into a file ; ask the FLAC command line program to transcode raw data to .flac file ; use ffplay to verify the results.

  I might develop some other uses for this library.