Recherche avancée

Sur d’autres sites (11052)

• Overlaying video with text - ffmpeg speed

  12 février 2017, par Sebadc

  I’m developing an app that has a functionality similar to Snapchat’s, in which you can add text to an existing video and save it on your phone.

  I got this to work using ffmpeg’s "-drawtext" filter. The problem is that I’m getting a noticable delay (20 seconds or so) when adding text to videos, even though they are not too big (around 10 seconds length).

  Can anyone point me in the right direction on how to reduce this delay ? Taking Snapchat as reference, they overlay high quality videos with text with little to no delay.

  I’ve read about extracting the video’s frames and overlaying them manually, but shouldn’t that take longer ?

  Thank you for your help.

• ffmpeg : How to change video duration (slow-down or speed-up) to exact value ?

  2 février 2017, par Moo

  I have miltiple videos with different durations and need to always set it to be exactly 10 seconds.

  I know that I can use -filter:v "setpts=speed*duration" but is there any way to make a universal one-line function to convert any-duration video to 10 seconds video ?

• Howto speed up Video Streaming with ffserver and ffmpeg + x265

  30 mars 2016, par binaryCode

  Below my ffserver.conf :

  Port 8090                      # Port to bind the server to
  
  BindAddress 0.0.0.0
  
  MaxHTTPConnections 2000
  
  MaxClients 1000
  
  MaxBandwidth 10000             # Maximum bandwidth per client
  
                             # set this high enough to exceed stream bitrate
  
  CustomLog -
  
  #NoDaemon                       # Remove this if you want FFserver to    daemonize after start
  
  
  
  <feed>               # This is the input feed where FFmpeg will send
  
   File /tmp/feed1.ffm            # video stream.
  
   FileMaxSize 1G              # Maximum file size for buffering video            # Allowed IPs
  
   ACL allow 127.0.0.1
  
  </feed>
  
  
  
  <stream>                       # Output stream URL definition
  
    Feed feed1.ffm              # Feed from which to receive video
  
    Format matroska
  
  
  
    # Audio settings
  
    AudioCodec vorbis
  
    AudioBitRate 64             # Audio bitrate
  
  
  
    # Video settings
  
    VideoCodec libx265
  
    VideoSize 720x576           # Video resolution
  
    VideoFrameRate 25           # Video FPS
  
    AVOptionVideo flags +global_header  # Parameters passed to encoder
  
                                     # (same as ffmpeg command-line  parameters)
  
    #AVOptionVideo cpu-used 0
  
    AVOptionVideo qmin 10
  
    AVOptionVideo qmax 42
  
    #AVOptionVideo quality good
  
    AVOptionAudio flags +global_header
  
    PreRoll 15
  
    StartSendOnKey
  
    VideoBitRate 400            # Video bitrate
  
   </stream>
  
  
  
   <stream>                    # Server status URL
  
     Format status
  
     # Only allow local people to get the status
  
     ACL allow localhost
  
    ACL allow 0.0.0.0
  
   </stream>
  
  
  
   <redirect>    # Just an URL redirect for index
  
      # Redirect index.html to the appropriate site
  
      URL http://www.ffmpeg.org/
  
   </redirect>

  and below is ffmpeg command to send my usb camera :

  c:\ffmpeg\bin\ffmpeg -f dshow -i video="A4TECH USB2.0 PC Camera"  -r 25 -s 320x240 -vcodec libx265 -preset ultrafast -tune zerolatency  http://119.81.216.43:8090/feed1.ffm

  ffmpeg running from my notebook with processor corei7 from Indonesia, and ffserver using ubuntu 14.x on ibm soflayer singapore,

  with above configuration i can play video streaming with 4s delay

  myquestion : howto improve speed so i can play video less than or equal 1 second, any idea ?