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• Zoom effect with ffmpeg always shows error [duplicate]

  13 août 2020, par asored

  How can I create a Ken Burns slow zoom effect in a with ffmpeg generated video ?

  


  I have this :

  


  'ffmpeg -r 12 -i $tempPath/img%04d.jpg -vcodec libx264 -y -an -vf "pad=ceil(iw/2)*2:ceil(ih/2)*2" $tempPath/$videoFileName.mp4'

  


  What I tried :

  


  'ffmpeg -r $12 -i $tempPath/img%04d.jpg -vcodec libx264 -y -an -vf "zoompan=z=if(lte(zoom,1.0),1.5,max(1.001,zoom-0.0015)):d=125" "pad=ceil(iw/2)*2:ceil(ih/2)*2" $tempPath/$videoFileName.mp4'

  


  But I get the error : Unable to find a suitable output format for 'pad=ceil(iw/2)*2:ceil(ih/2)*2'

  


  Where is the issue ?

  


• ffmpeg command not found but pip list shows ffmpeg

  7 mars, par your_doomsday07

  I have been trying to install ffmpeg using the command
pip install ffmpeg and I am doing this in a server where we dont have sudo permissions. On writing ffmpeg I get ffmpeg : command not found. Then I checked with pip list and it showed ffmpeg. Please help me.

  


• Multicast video captured via VLC shows a gray background for the first 1/2 second

  1er août 2014, par DavidG

  I am capturing multicast video using VLC.exe and performing some processing/converting using FFmpeg.exe. The resulting video starts with a gray background with some of the moving objects moving through the gray background. This seems to me that the video is not starting on an I-Frame, but on a B-Frame or a P-Frame. However, when I run ffprobe, it states the first frame is a key frame. After about 1/2 second, the video plays fine.

  Here is the command I’m using to capture the video :

  vlc.exe -I curses --run-time=10 "my.sdp" --sout=video.mp4

  I’m not using anything special when I convert to an mp4 file using FFmpeg :

  ffmpeg.exe -i video.mp4 -s 400x300 final.mp4

  I tried to post an image of the first frame or two, but Stackoverflow gave me an error stating I need at least 10 reputation to post images. Sorry about that, an image would have helped.

  I ran the command "ffprobe show_frames " and it looks like the first frame is a key frame. Of course I’m new to all this and I don’t know what I’m doing or seeing.

  Here is beginning of the output to the "ffprobe show_frames " command :

  [FRAME]
  
  media_type=video
  
  key_frame=1
  
  pkt_pts=0
  
  pkt_pts_time=0.000000
  
  pkt_dts=0
  
  pkt_dts_time=0.000000
  
  pkt_duration=1001
  
  pkt_duration_time=0.033367
  
  pkt_pos=48
  
  pkt_size=756
  
  width=400
  
  height=300
  
  pix_fmt=yuv420p
  
  sample_aspect_ratio=1:1
  
  pict_type=I
  
  coded_picture_number=0
  
  display_picture_number=0
  
  interlaced_frame=0
  
  top_field_first=0
  
  repeat_pict=0
  
  reference=3
  
  [/FRAME]

  Is there any way to either tell VLC.exe to start capturing on an I-Frame (This would be the best solution as I specify a duration to capture the video) or is there a way to tell FFmpeg.exe to start converting the input video starting at the first I-Frame encountered ?

  Thanks,
   David