Recherche avancée

Sur d’autres sites (11983)

• FFMPEG Wipe transition one layer over another

  25 juillet 2021, par Dan Weaver

  How to reveal one layer over another with a wipe transition using FFMPEG ?

  


  

  


  NOTE : this is not a slide transition. The top image stays in one position but is gradually revealed over time.

  


  I'd like a technique that can work for top layers with or without transparency and for images, videos or dynamically created sources, like showwavespic.

  


  I tried making a mask animation like so :

  


  

  


  but alphamerge doesn't work as I expected it to and I can't find a blend mode that works with this type of mask.

  


  EDIT : The xfade filter was suggested but it doesn't seem to work with when source has transparency. It renders transparent areas black. Example with transparent source :

  


  

  


  But xfade renders this :

  


  

  


• unwanted bitrate reduction in MOD to mp4 conversion with ffmpeg

  18 juillet 2014, par Brian

  My Panasonic camcorder records video to a .MOD file.
  On Windows... (my linux box currently has network issues :)

  ffmpeg -i file.MOD

  yields

  bitrate: 9579 kb/s
  
  video: mpeg2video yuv 420p 704x480 [SAR 10:11 DAR 4:3] 
  
  29:97 fps, 29.97 tbr, 90k tbn, 59.94 tbc

  I tried

  ffmpeg -loglevel verbose -i file.MOD file.mp4
  
  ffmpeg -loglevel verbose -i file.MOD -qscale 0 file.mp4
  
  ffmpeg -loglevel verbose -i file.MOD -qscale 1 file.mp4

  Each of these yields the same bitrate of 2604 and a video codec of h264 (High).
  My original file was 22,786 KB and the new files are each 6,217 KB.

  My goal/purpose is for lossless conversion of the .MOD files for video editing, probably using blender.

  So my big question is "How do I do lossless video conversion of .MOD files using ffmpeg to a format that blender and other common video editing tools can work with ?"

  But for educational purposes (and posterity) I am also curious why the bitrate is being reduced by the conversions above and why there is no difference when using the -qscale argument.

• How to make video (of any format) compatible to play in android's default player ?

  24 janvier 2014, par Aarti

  I want to play video urls from server in device's video player,but unable to play all videos
  Testing on HTC Desire (4.1.1), Panasonic (4.1.3), Samsung G S2(2.3.6).

  I've already gone through following links

  Sorry, this video cannot be played - streaming mp4 to android and
  How to Play Streaming Audio/Video from a url ?
  but did not found working solution.

  I understand few imp things from above,

  1. Video must be baseline H264 encoded for playing successfully on all devices
  2. For encoding any kind of video to H264, we need to integret ffmpeg

  My questions are,

  1. How exactly I can convert any format of video to H264 baseline support ? Examples are appreciated.
  2. Is there any alternate way for FFMPEG ?
  3. How can I check if video is baseline H.264 ?

  I have tried playing videos with both Intent ACTION_VIEW & MediaController, result was same for both.

  Its very urgent. Any kind of help or hint appreciated. Thank You.