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• ffmpeg, add static image to beginning and end with transitions

  14 mars 2021, par CreateChange

  ffmpeg noob here, trying to help my mother with some videos for real estate walkthroughs. I'd like to set up a simple pipeline that I can run videos through and have outputted as such :

  


  

  • 5 second (silent) title card ->

  


  • xfade transition ->

  


  • property walk through ->

  


  • xfade transition ->

  


  • 5 second (silent) title card

  


  


  Considerations :

  


  

  • The intro / outro card will be the same content.

  


  • The input walkthrough videos will be of variable length so, if possible, a dynamic solution accounting for this would be ideal. If this requires me to script something using ffprobe, I can do that - just need to gain an understanding of the syntax and order of operations.

  


  • The video clip will come in with some audio already overlaid. I would like for the title cards to be silent, and have the video/audio clip fade in/out together.

  


  


  I have gotten a sample working without the transitions :

  


  ffmpeg -loop 1 -t 5 -i title_card.jpg \
    -i walkthrough.MOV \
    -f lavfi -t 0.1 -i anullsrc \
    -filter_complex "[0][2][1:v][1:a][0][2]concat=n=3:v=1:a=1[v][a]" \
    -map "[v]" -map "[a]" \
    -vcodec libx265 \
    -crf 18 \
    -vsync 2 \
    output_without_transitions.mp4


  


  I have been unable to get it to work with transitions. See below for the latest iteration :

  


  ffmpeg -loop 1 -t 5 -r 60 -i title_card.jpg \
    -r 60 -i walkthrough.MOV \
    -f lavfi -t 0.1 -i anullsrc \
    -filter_complex \
    "[0][1:v]xfade=transition=fade:duration=0.5:offset=4.5[v01]; \
    [v01][0]xfade=transition=fade:duration=0.5:offset=12.8[v]" \
    -map "[v]" \
    -vcodec libx265 \
    -crf 18 \
    -vsync 2 \
    output_with_transitions.mp4


  


  This half-works, resulting in the initial title card, fading into the video, but the second title card never occurs. Note, I also removed any references to audio, in an effort to get the transitions alone to work.

  


  I have been beating my head against the wall on this, so help would be appreciated :)

  


• ffmpeg created blank video

  12 janvier 2023, par eZi0

  I am using images to create a video.
The path and everything is perfect.The same code is working at another place but not here. 
A file gets created with size 0 kb.

$cmd = 'ffmpeg -framerate 1/1.5 -i ../static/tours/' . $tourId  . '/imageset/original/temp/%05d.jpg -c:v libx264 -r 30 -pix_fmt yuv420p ../static/tours/' .$tourId . '/videos/' . $downloadid . 'video.mp4';                            

exec($cmd,$output,$error);

this is command for which the code is working
 ffmpeg -framerate 1/1.5 -i ../static/tours/6115857/imageset/original/temp/%05d.jpg -c:v libx264 -r 30 -pix_fmt yuv420p ../static/tours/6115857/                      flashvideos/1648358770flashvideo.mp4

Here its not working:-
ffmpeg -framerate 1/1.5 -i ../static/tours/7275871/imageset/original/temp/%05d.jpg -c:v libx264 -r 30 -pix_fmt yuv420p ../static/tours/7275871/videos/1011821725video.mp4



  


  I tried changing to vcodec instead of -c:v

  


  Tried changing framerate to 60

  


• ffmpeg fast but accurate seek in avi

  21 mars 2019, par C.M.

  I’ve built a small pipeline to automatically cut and enhance video files which I recorded.

  I detect scenes by using the ffmpeg’s select='gt(scene,0.4)',showinfo filter. After parsing these information I run ffmpeg for each scene to produce single video files for them, for example :

  ffmpeg -y -i test.avi -ss 00:00:00.00 -to 00:00:54.61 -c copy test_1.avi
  
  ffmpeg -y -i test.avi -ss 00:00:54.61 -to 00:01:38.21 -c copy test_2.avi
  
  ffmpeg -y -i test.avi -ss 00:01:38.21 -to 00:01:59.45 -c copy test_3.avi
  
  [...]

  As you can see I use the -ss and -to parameters to specify where the output files should start and end. This is working very well but it becomes very, very slow over time since my original file size is 50 gigabytes.

  I guess that -ss lets ffmpeg seek from the beginning of the original file to the start time as I can observe disk action when seeking.

  Placing the -ss param before the -i input file is faster but very inaccurate (off by some seconds).

  Is there maybe any trick to increase the cut/trim performance without losing the accuracy ?

  I also tried to convert the input file to MP4 which decreases the file size and seek time significantly. But then I had keyframe errors and I want to operate on the original files.

  Thank you !