Recherche avancée

Sur d’autres sites (6125)

• Concatenating image with video for Freeze frame effect

  12 mai 2015, par Code_Ed_Student

  I am currently trying to achieve with ffmepg a freeze frame effect. This is something easy to do with adobe after effects shown here. However I would like to achieve a freeze frame effect(of 5 seconds duration) followed by the 15 second video for the final output video. This should amount to a final duration of 20 seconds. However with the settings below, I am getting a still image with the video following but it does not show a "freeze frame effect". How can I achieve a "freeze frame effect" in ffmpeg ?

  //create image

  ffmpeg -i "/media/test/test.mp4" -ss 00:00:00.023222 -vframes 1 "/media/test/test.png"

  //create freeze image effect

  ffmpeg -i "/media/test/test.mp4" -loop 1 -i "/media/test/test.jpg" -an \
  
  -filter_complex "[1:v]trim=start=0:end=5[ol];[0:v]setpts=[nv];[nv][ol]overlay=eof_action=pass[final]" \
  
  -map '[final]' -c:a aac -strict experimental -c:v libx264 -q 1 "/media/test/test_effect.mp4"

• lavc/dxv : assume DXV2 files use premultiplied alpha

  11 février 2024, par Connor Worley

  lavc/dxv : assume DXV2 files use premultiplied alpha
  I generated a DXV2 file with an interesting alpha channel using
  
  Adobe Media Encoder 2015 and compared decoding it using Resolume Alley
  
  and ffmpeg. Similarly to DXV3 files, Alley expects premultiplied alpha
  
  and ffmpeg matches its decoding more closely when it does the same.
  Reference file : https://connorworley.com/dxv2-dxt5.mov
  Existing FATE tests for DXV2 files do not cover this change.
  Signed-off-by : Connor Worley <connorbworley@gmail.com>
  
  Signed-off-by : Anton Khirnov <anton@khirnov.net>
  

  • [DH] libavcodec/dxv.c

• Vertical video play does not sync with multiple stacked video

  5 novembre 2018, par Sabha

  I dont know if I have wrote the subject well and if that can be understood. Nevertheless, here is an explanation

  I have 7 videos of different dimensions where the width is same (1080). I wish to place them one below the other to get a full hd vertical video (1080x1920). I tried the -filter_complex vstack filter in ffmpeg and got all the videos aligned one below the other and I am getting a perfect 1080x1920 full hd vertical video but they dont sync with each other. Once the videos are in sync, I need to put an audio too which should also sync with the in-sync video that will be made.

  There is so much of complexity. Please advice how do I make them sync. Is there any software that can allow me to put 7 videos one below the other in a timeline ? (if not 7, atleast 3-4 videos). Please advice where and how to start.

  Is there any option in Adobe Premier or any other software ?

  Thanks

  EDIT : I am doing a very long procedure to combine all 7 videos vertically

  first i use

  ffmpeg -i video1.mp4 -i video2.mp4 -preset veryslow -filter_complex vstack video12.mp4

  and then

  ffmpeg -i video12.mp4 -i video3.mp4 -preset veryslow -filter_complex vstack video123.mp4

  so on and so forth

  Is there a better way to do it all in one command ?