Recherche avancée

Sur d’autres sites (12756)

• Create thumbnails of sections of a torrent stream

  14 juillet 2015, par Ortixx

  I’m trying to create a little application in nodejs using the torrent-stream library to create thumbnails of a video without actually having to download the entire file. I was thinking of downloading only 10 parts, out of which I would extract an image, but then the encoding comes into play : without an I-frame I cannot extract an image out of the stream, and there is no way of me knowing where the I-frame is.

  So any ideas on how to do this ? Basically I was hoping to create 10 tiny files which I could then open in ffmpeg in order to save a thumbnail (this would give me 10 thumbnails which is want I want). I’m just not sure how to handle the stream.

• Anomalie #3305 (Nouveau) : Balise fermée automatiquement dans un bloc code

  21 octobre 2014, par Franck Dalot

  Bonjour
  Je viens de me rendre compte d’un bug sur contrib (le bug est également présent sous SPIP 3.0.18-dev [21616]) mais semble absent sous spip 3.1
  Quand une personne répond dans le forum en entourant par "code"

  <necessite version="[2.0.0;2.1.99]"></necessite>
  La prévisalisation est ok, par contre après avoir valider le message, cela écris :
  <necessite version="[2.0.0;2.1.99]"></necessite>
  Cordialement, Franck

• Recording video in C#

  31 juillet 2014, par pfedotovsky

  I have to do the following : record video from camera using C#. Camera I use produces video frames (framerate is not fixed) and I have to somehow put all the frames together and create video file. Also I need to use different codecs such as AVI or MPEG4 (these codecs are required, others are optional).

  The main problem I faced is how to create video in which framerate is not fixed. I have a stream of frames, for example I can recive the first frame after 1ms, then after 20ms, then 36ms and so on. If I create video with 25 frames/second the result will be wrong because it means that frames are added after 40ms.

  I tried to use Aforge.Video library, it has a method http://www.aforgenet.com/framework/docs/html/84a560df-bfd5-e0d6-2812-f810b56a254d.htm which adds a frame according to timespan. But this method has problems with setting bitrate - the bitrate value I pass to the method simply ignored (http://www.aforgenet.com/forum/viewtopic.php?f=2&t=2665).

  So my questions is : is there some C# library which I can use to video recording ? I have to support AVI and MPEG4, also possibility to set bitrate and the last but not the least - record video with variable framerate.

  Thanks in advance. Any suggestions would be very helpful.

  UPD1 : I can’t connect to camera directly - all I have is a stream of frames and I need to convert this stream to video at run-time.

  UPD2 : A library I’m looking for should satisfy the following properties. It has to contain a method (or some way how to do the same) to add next frame with a timestamp just like in Aforge.Video.FFMPEG :

  public void WriteVideoFrame(Bitmap frame, TimeSpan timestamp)

  And it should be possible to choose different codecs (at least AVI and MPEG4) and also to set bitrate.
  Is there some alternatives to Aforge.Video.FFMPEG ? Because Aforge doesn’t work properly - the bitrate value is ignored, also some codecs are not supported (MPEG2 for example).

  UPD3 : One more questions about codec license. If I use open source library, should I worry about the codec license ?