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• how to implement streaming feautre on our website

  14 février 2023, par Mohamed Taha

  we are building a website -for education purpose -and want to add streaming function on it

  


  our website like a social media platform so someone want to strat streaming (the media will be either from camera or screen sharing )

  


  from where i can start

  


  i have searched about this topic and i arrived at knowing the theortical steps to stream video
_ capture ,encoding , mixin ,send to server
but though i don't know where to start too

  


  i found tool called FFmpeg can do this but on windows platform and i think won't help.

  


• php ffmpeg 3gp watermark not working

  14 juin 2013, par Febin Baiju

  I am completely new to php ffmpeg. I tried to watermark a 3gp video in my shared ffmpeg installed server. But it doesn't output anything other than LOADED as stated in the code. The ouput is also not creating. Can anyone please solve the problem ?

  <?php
  
  if(extension_loaded('ffmpeg')){
  
  echo 'LOADED';
  
  $c = 'ffmpeg –i video.3gp -vf "movie=watermark.png [watermark]; [in][watermark] overlay=10:main_h-overlay_h-10 [out]" outputvideo.3gp';
  
  exec($c);
  
  }
  
  ?>

  When i used phpinfo() what i get about ffmpeg is

  ffmpeg
  
  ffmpeg-php version 0.6.0-svn
  
  ffmpeg-php built on May 10 2013 11:50:44
  
  ffmpeg-php gd support enabled
  
  ffmpeg libavcodec version Lavc52.122.0
  
  ffmpeg libavformat version Lavf52.110.0
  
  ffmpeg swscaler version SwS0.14.1
  
  ffmpeg.allow_persistent 0 0
  
  ffmpeg.show_warnings 0 0

• How can I learn the effective quality of the h264_nvenc encoder ?

  24 septembre 2020, par pfdint2

  I seek to ascertain the end-product quality of various cq ("constant quality") values for the h264_nvenc video encoder.

  


  To use the h264_nvenc encoder through ffmpeg and with a target quality, I follow the instructions in Nvidia's documentation, last paragraph of the linked anchor.

  


  I specify a Variable Bit Rate rate control mode (rc=vbr_hq) and a target quality (cq=). This should be enough to test various values of cq. The story should end there.

  


  HOWEVER, that only outputs the same perfect quality video of extremely large size for any cq value. (Using cq=1, cq=20, and cq=51 all output a file with the same hash.)

  


  Per documentation, I can also specify a maxBitRate (maxrate=). If I don't specify a maxrate, the documentation indicates :

  


  


  If maxBitRate is not specified, the encoder will use as many bits as needed to achieve the target quality.

  


  


  But that's not the behavior I'm observing. I'm seeing the encoder use as many bits as possible, not as many bits as needed. The resultant video has an overall bitrate of 100Mb/s. Double the source video.

  


  If I do set a maxrate, it is observed by the encoder. But if I have to set the bitrate correctly for every cq value, what is the point of the cq value ? I would just set cq=1 and test various bitrates, which would then only be applicable to a specific video.

  


  Is there some warning or output that notes that the bitrate was insufficient to reach the target quality that I'm not seeing ? That would at least allow me to brute force this.

  


  Or am I misunderstanding the relationship between these settings ?