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• Evolution #3849 : Affiner/retirer les disallow de robots.txt qui empêchent les sites SPIP de se ré...

  28 octobre 2016, par Spipmalion Dupond

  Merci pour ta réponse
  Effectivement, je viens d’activer la compression et cela va régler la plupart des problèmes d’accès par Google

  C’est quand même embêtant pour les sites qui n’activent pas la compression puisqu’elle n’est pas obligatoire, et aussi la compression ne compresse pas 100% des fichiers chez moi : http://forum.spip.net/fr_265551.html

• Internecine Legal Threats

  1er juin 2011, par Multimedia Mike — Legal/Ethical

  FFmpeg and associated open source multimedia projects such as xine, MPlayer, and VLC have long had a rebel mystique about them ; a bunch of hackers playing fast and loose with IP law in order to give the world the free multimedia experience it deserved. We figured out the algorithms using any tools available, including the feared technique of binary reverse engineering. When I gave a presentation about FFmpeg at Linuxtag in 2007, I created this image illustrating said mystique :

  
  
  

  It garnered laughs. But I made the point that we multimedia hackers just press on, doing our thing while ignoring legal threats. The policy has historically worked out famously for us– to date, I seem to be the only person on the receiving end of a sort-of legal threat from the outside world.

  Who would have thought that the most credible legal threat to an open source multimedia project would emanate from a fork of that very project ? Because that’s exactly what has transpired :

  
  
  Click for full threat
  

  So it came to pass that Michael Niedermayer — the leader of the FFmpeg project — received a bona fide legal nastygram from Mans Rullgard, a representative of the FFmpeg-forked Libav project. The subject of dispute is a scorched-earth matter involving the somewhat iconic FFmpeg zigzag logo :

  Original 2D logo		enhanced 3D logo

  To think of all those years we spent worrying about legal threats from organizations outside the community. I’m reminded of that time-honored horror trope/urban legend staple : Get out ! The legal threats are coming from inside the house !

  I’m interested to see how this all plays out, particularly regarding jurisdiction, as we have a U.K. resident engaging an Italian lawyer outfit to deliver a legal threat to an Austrian citizen regarding an image hosted on a server in Hungary. I suspect I know why that law firm was chosen, but it’s still a curious jurisdictional setup.

  People often used to ask me if we multimedia hackers would get sued to death for doing what we do. My response was always, “There’s only one way to know for sure,” by which I meant that we would just have to engage in said shady activities and determine empirically if lawsuits resulted. So I’m a strong advocate for experimentation to push the limits. Kudos to Michael and Mans for volunteering to push the legal limits.

• How to Output Mjpeg from Kokorin Jaffree FFmpeg via UDP to a Localhost Port ?

  14 octobre 2022, par roba

  I have a Java program which displays dual webcams and records them to file in FHD 30fps H264/H265. It uses Sarxos Webcam for the initial setup and display but when recording, it switches to Jaffree FFmpeg. During recording Sarxos Webcam must release its webcam access and cannot display while recording continues.

  


  I have tried recording with Xuggler/Sarxos but Sarxos seems to only access raw video from the webcams which creates limitations in the frame rate and resolution which can be achieved. At 1920x1080 the cameras can only deliver 5 fps raw video.

  


  I am trying to direct mjpeg streams from Jaffree to localports for display purposes during recording but I cannot figure out how to do it.

  


  Simultaneous recording plus sending to a port can be done from the terminal with the following :

  


  ffmpeg -f  dshow  -video_size 1920x1080 -rtbufsize 944640k -framerate 25 -vcodec mjpeg  -i video="Logitech Webcam C930e" -pix_fmt yuv420p -c:v libx264 outFHDx25.mp4 -f mpegts udp://localhost:1234?pkt_size=188&buffer_size=65535


  


  and viewed from the port in a different terminal like this :

  


  ffplay -i udp://localhost:1234


  


  The video which displays is a little blocky compared with the video recorded to file. Any suggestions on how to improve this would be appreciated.

  


  Note that FFPlay is not included in Jaffree FFMpeg.

  


  I would like to send the mjpeg to a port and then read it into the Sarxos Webcam viewer to display while recording is in progress.

  


  The Jaffree Java code for recording the output of one webcam to file follows. It takes the mjpeg/yuv422p output from the webcam and normally encodes it to file as H264/yuv420p :

  


  public static FFmpeg createTestFFmpeg() {
      String camera1Ref = "video=" + cam1Vid + ":audio=" + cam1Aud;
          return FFmpeg.atPath()
              .addArguments("-f", "dshow")  //selects dshow for Windows
              .addArguments("-video_size", resString)  //video resolution  eg 1920x1080          
              .addArguments("-rtbufsize", rtBufResultString) 
              .addArguments("-thread_queue_size", threadQ)
              .addArguments("-framerate", fpsString)   // capture frame rate  eg 30fps         
              .addArguments(codec, vidString)  //set capture encode mode from camera
              .addArgument(audio) //on or off
              .addArguments("-i", camera1Ref)   // name of camera to capture
              .addArguments("-pix_fmt", pixFmt)
              .addArguments("-c:v", enc2)  //eg enc2 = "libx264", "h264_nvenc"
              .addArguments(enc3, enc4)  //enc3 = "-crf", enc4 = "20"
              .addArguments(enc5, enc6)  //enc5 = "-gpu:v", enc6 = "0"
              .addArguments(enc7, enc8)  //enc7 = "-cq:v", enc8 = "20"
              .addArguments(enc9, enc10)  //enc9 = "-rc:v", enc10 = "vbr"
              .addArguments(enc11, enc12)  //enc11 = "-tune:v", enc12 = "ll"
              .addArguments(enc13, enc14)  //enc13 = "-preset:v", enc14 = "p1" 
              .addArguments(enc15,enc16)  //enc15 = "-b:v", enc16 = "0"
              .addArguments(enc17, enc18)  //enc17 = "-maxrate:v", enc18 = "5000k"
              .addArguments(enc19, enc20)  //enc19 = "-bufsize:v", enc20 = "5000k"
              .addArguments(enc21, enc22)  //enc21 = "-profile:v", enc22 = "main"
              .addArgument(noFFStats) //"-nostats"{, stops logging progress/statistics
              .addArguments("-loglevel", ffLogLevel)  //error logging
              .addArgument(bannerResultString)  // "-hide_banner"
              .addArguments("-rtbufsize", rtBufResultString) 
              .setOverwriteOutput(true)   // overwrite filename if it exists  Boolean = overwriteFile
              .addOutput(
                  UrlOutput
                      .toUrl(filePathL))                    
              .setProgressListener(new ProgressListener(){
                  @Override
                  public void onProgress(FFmpegProgress progress){
                     if(ffProgress){ 
                          System.out.println(progress);
                          
                     } 
                    }
            } );
            
   }


  


  How and where do I add the code to output mjpeg via UDP to a localport while simultaneously writing H264 to a file, and what is the syntax ? I am sure it must be simple but I seem to have tried all of the permutations without success. I can write to a file OR I can output to a port but I cannot do both.