Recherche avancée

Sur d’autres sites (7445)

• MediaElement ffmpeg windows 8.1 [on hold]

  30 mai 2014, par user3084145

  how can in read an ffmpeg stream in windows 8.1 app
  i’ve tryed with MediaElement but didn’t work

• ffmpeg is dropping frames and only using 1/10 cpu [on hold]

  7 décembre 2013, par wlraider70

  I have some old hardware so I'm not expecting miracles. I want to stream from a webcam to ustream at standard quality.

  I'm using a code like

  sudo ffmpeg -re -f v4l2 -i /dev/video1 -f flv "rtmp://1.16543hvtJ6aU flashver=FME/2.5\20(compatible;\20FMSc\201.0)"

  or

     sudo ffmpeg -re -f v4l2 -r 25 -s 640x480 -i /dev/video1 -f flv "rtmp://1.166aU flashver=FME/2.5\20(compatible;\20FMSc\201.0)

  I'm getting results like

  Tasks: 102 total,   1 running,  99 sleeping,   2 stopped,   0 zombie
  
  Cpu(s):  5.7%us,  0.7%sy,  0.0%ni, 93.6%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
  
  Mem:   1920560k total,   339028k used,  1581532k free,    19112k buffers
  
  Swap:  1963004k total,        0k used,  1963004k free,   129300k cached
  
  
  
    PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
  
   3176 root      20   0  222m  31m  24m S  5.0  1.7   0:01.60 ffmpeg

  and

    Metadata:
  
      encoder         : Lavf53.32.100
  
      Stream #0:0: Video: flv1 ([2][0][0][0] / 0x0002), yuv420p, 640x480, q=2-31, 200 kb/s, 1k tbn, 30 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo -> flv)
  
  Press [q] to stop, [?] for help
  
  frame=  330 fps=  5 q=2.5 size=     808kB time=00:01:02.70 bitrate= 105.5kbits/s dup=0 drop=137

  How can I push the system harder or figure out where my bottleneck is ?

• Node.js Webm live stream server : issues with tag

  10 décembre 2013, par breathe0

  I'm using Node.js as stream server to stream realtime Webm videos that is sent by FFMPEG (executed from another application, the stream is done via HTTP) and received by a webapp that uses the tag.

  This is what I'm doing : FFMPEG streams the received frames using the following command :

  ffmpeg -r 30 -f rawvideo  -pix_fmt bgra -s 640x480 
  
  -i \\.\pipe\STREAM_PIPE -r 60 
  
  -f segment  -s 240x160 -codec:v libvpx  -f webm 
  
  http://my.domain.com/video_stream.webm

  (the stream comes from an application that uses the Kinect as source and communicates with FFMPEG through a pipe, sending one frame after another)

  When the webapp connects, it receives immediately this response from the server :

  HTTP/1.1 200 OK
  
  X-Powered-By: Express
  
  content-type: video/webm
  
  cache-control: private
  
  connection: close
  
  Date: Fri, 06 Dec 2013 14:36:31 GMT

  and a Webm header (previously stored on the server, with the same resolution and frame rate of the source stream and tested as working on VLC) is immediately appended. Then the webapp starts to receive the data streamed by FFMPEG. Here is a screenshot of Mkvinfo GUI showing the fields of the header :

  

  However, even if the Network tab of the Chrome console shows that there is an actual stream of data (meaning that what is streamed is not completely garbage, otherwise the connection would be dropped), the player doesn't display anything. We tried to manually prepend our header to the dumped video received by the webapp and VLC plays it just fine, but this is not happening with the tag.

  What can cause this problem ? Are we missing something about the encoding on the FFMPEG side or we stored wrong values on the header (or they're not enough) ?

  PS : I cannot rely on an extern stream server.

  PPS : We tried the following experiments :

  • substituting the video header with the one stored in the server makes the video playable on both vlc and video tag
  • if we dump the video that is already started (without an header) and we prepend the video header stored in the server or even its original header, the video is playable in VLC but not on the tag (we're carefully prepending the header just before the beggining of the cluster).