Sur d’autres sites (13000)

• Capture raw video byte stream for real time transcoding

  9 septembre 2012, par user1145905

  I would like to achieve the following :

  Set up a proxy server to handle video requests by clients (for now, say all video requests from any Android video client) from a remote video server like YouTube, Vimeo, etc. I don't have access to the video files being requested, hence the need for a proxy server. I have settled for Squid. This proxy should process the video signal/stream being passed from the remote server before relaying it back to the requesting client.

  To achieve the above, I would either

  1. Need to figure out the precise location (URL) of the video resource being requested, download it really fast, and modify it as I want before HTTP streaming it back to the client as the transcoding continues (simultaneously, with some latency)

  2. Access the raw byte stream, pipe it into a transcoder (I'm thinking ffmpeg) and proceed with the streaming to client (also with some expected latency).

  Option #2 seems tricky to do but lends more flexibility to the kind of transcoding I would like to perform. I would have to actually handle raw data/packets, but I don't know if ffmpeg takes such input.

  In short, I'm looking for a solution to implement real-time transcoding of videos that I do not have direct access to from my proxy. Any suggestions on the tools or approaches I could use ? I have also read about Gstreamer (but could not tell if it's applicable to my situation), and MPlayer/MEncoder.

  And finally, a rather specific question : Are there any tools out there that, given a YouTube video URL, can download the byte stream for further processing ? That is, something similar to the Chrome YouTube downloader but one that can be integrated with a server-side script ?

  Thanks for any pointers/suggestions !

• FFMPEG real-time buffer full frame dropped

  27 janvier 2015, par Burgaz

  I’m using FFMPEG on windows with direct show.
  I’m streaming RTMP (command below) and i need very low latency.
  Once run I get the following errors : [dshow @ 024ce800] real-time buffer 204% full ! frame dropped !

  ffmpeg -threads 6 -f dshow -i video=UScreenCapture -s 1920x1080 -an -vco
  dec libx264 -x264opts keyint=25:min-keyint=20 -b:v 1024k -preset ultrafast -tune zerolatency -crf 22 -r 10 -pix_fmt yuv420p -f flv rtmp ://server...

  Do you have an idea how to handle this kind of error ?

  Thanks
  Ronen

• FFMPEG : Queue input is backward in time & invalid, clipping issue [on hold]

  22 octobre 2013, par Sai

  I am using FFMPEG to convert the following video from wmv to flv and getting errors.

  Command is

  ffmpeg -i Sample.wmv  -qscale 0 -s 472x314 -ar 22050 -ac 1 -ab 96k  -g 5 Sample.flv

  I am getting these errors

  [libmp3lame @ 000000000030b640] Queue input is backward in time
  
  [flv @ 00000000003e6b20] st:0 PTS: 560 DTS: 560 < 577 invalid, clipping

  Although the file is getting converted from the command line. Conversion is being interrupted after integrating with my application.

  And the video size is 300MB

  Any idea why these errors were coming ?