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• Wave Goodbye ; What About VP8/WebM ?

  7 août 2010, par Multimedia Mike — Multimedia PressWatch

  Some big news in the geek community this past week came in the form of Google’s announcement that it would no longer be caring about its vaunted Wave technology. I was mildly heartbroken by this since I had honestly wanted to try Google Wave. Then I remembered why I never got a chance to try it : they made it an exclusive club at the beginning. I really did try to glean some utility out of the concept by reading documentation and watching videos and I had some ideas about how I might apply it. Then again, I try to think of a use for nearly any technology that crosses my path.

  It still struck me as odd : Why would Google claim that no one was interested in their platform when they wouldn’t give anyone a chance to try it out ? A little digging reveals that Google did open it for general use back around May 18. That date sounds familiar... oh yeah, VP8 was open sourced right around the same time. Maybe that’s why I don’t remember hearing anything about Wave at the time.

  But now I’m wondering about VP8 and WebM. How long do you think it might be before Google loses interest in these initiatives as well and reassigns their engineering resources ? Fortunately, if they did do that, the technology would live on thanks to the efforts of FFmpeg developers. A multimedia format has a far more clear-cut use case than Google Wave.

• How connect OBS with VPS which has ffmpeg for live streaming ?

  6 mai 2017, par user7647539

  Helo I’ve a VPS on Centos 7 with Apache and ffmpeg.
  How can I do live streaming on this server using OBS on my local PC to encode and publish to this server and after embed this live video in my wordpress website to allow every device to watch the live video ?
  Thank you all

• Recording of Full HD 60 FPS videos in C#

  17 mars 2021, par Alexander Naumov

  My application works with a high-speed camera. I am trying to record a videofile using C#.

  


  The task is pretty "simple" : to record the video from the camera. We need to record medium (higher-better) quality videos to save as many details as possible.

  


  

  • Resolution : 1920 x 1080 (FullHD)

  


  • Frames per second (FPS) : 60

  


  • Bitrate : I've started from 10000*1000 (but now I don't know)

  


  • Mediacontainer : MP4, AVI (does not really matter, we just need to
solve our task)

  


  • Codec : also does not matter, we just need speed and quality.

  


  • Maximum size of videofile : 10 GB/hour

  


  


  Framerate of the camera can be changed during the recording by the camera itself (not by user), so it's necessary to have something like timestamps for every frame or anything else.

  


  The problem is not fast enough recording.
Example : using AForge libs, generated pictures ("white" noise), duration of test videos is 20 seconds.

  


  Duration of video creating using different codecs (provided by AForge) :

  


  

  • Codec : MPEG4, Time : 33,703

  


  • Codec : WMV1, Time : 45,338

  


  • Codec : WMV2, Time : 45,530

  


  • Codec : MSMPEG4v2, Time : 43,775

  


  • Codec : MSMPEG4v3, Time : 44,390

  


  • Codec : H263P, Time : 38,894

  


  • Codec : FLV1, Time : 39,151

  


  • Codec : MPEG2, Time : 35,561

  


  • Codec : Raw, Time : 61,456

  


  


  Another libs we've tried is not satisfied us.
Accord.FFMPEG is slow because of strange inner exceptions.
EmguCV.FFMPEG has no timestamps, therefore it creates corrupted video.

  


  Recording the video to the SSD drive did not give us any visible acceleration.

  


  Google search gives no clear examples or modern solutions to solve this task. That's the main reason to write here.

  


  There is a code sample of our test :

  


  private static void AForge_test()
    {
        Console.WriteLine("AForge test started...");
        unsafe
        {
            Stopwatch watch = new Stopwatch();

            Console.WriteLine("FPS: {0}, W:{1}, H:{2}, T:{3}", fps, w, h, time);

            AForge.Video.FFMPEG.VideoCodec[] codecs = (AForge.Video.FFMPEG.VideoCodec[]) Enum.GetValues(typeof(AForge.Video.FFMPEG.VideoCodec));

            for(int k = 0; k < codecs.Length; k++)
            {
              /*  if (codecs[k] != VideoCodec.MPEG4)
                    continue;*/
                try
                {
                    watch.Restart();

                    Random r2 = new Random(200);
                    AForge.Video.FFMPEG.VideoFileWriter vw = new AForge.Video.FFMPEG.VideoFileWriter();
                    string name = String.Format("E:\\VideosHDD\\AForge_test_{0}_mid.avi", Enum.GetName(typeof(AForge.Video.FFMPEG.VideoCodec), codecs[k]));
                    vw.Open(name, w, h, fps, codecs[k], 10000 * 1000);

                    for (int i = 0; i < frames; i++)
                    {
                        vw.WriteVideoFrame(bmps[i%N]);
                    }

                    vw.Close();
                    vw.Dispose();

                    watch.Stop();

                    Console.WriteLine("Codec: {0}, Time: {1:F3}", Enum.GetName(typeof(AForge.Video.FFMPEG.VideoCodec), codecs[k]), watch.ElapsedMilliseconds / 1000d);
                }
                catch(Exception ex)
                {
                    Console.WriteLine("Error " + codecs[k].ToString());
                }

            }
            
        }

        Console.ReadKey();
    }


  


  Additional :

  


  

  1. We are ready to use not-for-free solutions, but free is preferable.

  


  2. One of the supposed reasons for low recording speed : (x86) building of applications. I tried so hard to find x64 Aforge building but failed in this. We really don't know is there any influence of application architecture on recording speed.

  


  


  I am ensured that I don't know all the background of video recording and another "little" thing, so I would be very pleased to solutions with clear explanations.