Recherche avancée

Sur d’autres sites (7784)

• How I can overlay video onto another video start from 2 second to 4 second ?

  23 janvier 2023, par KoliK

  I need overlay video onto another video start from 2 second to 4 second.

  


  I use ffmpeg for overlaying video onto another video for this command
ffmpeg -i tmp/test_screen_1672755242397.mp4 -vf "movie=tmp/test_camera_1672755249551.mp4, scale=250: -1 [inner]; [in][inner] overlay =10: 10 [out]" completed.mp4
But video test_camera_1672755249551 must be to star from 2 second and end to 4 second. What I need to add in command for result ?

  


• Cut a video in between key frames without re-encoding the full video using ffpmeg ? [closed]

  13 juillet 2024, par bguiz

  I would like to cut a video at the beginning at any particular timestamp, and it need to be precise, so the nearest key frame is not good enough.

  


  Also, these videos are rather long - an hour or longer - so I would like to avoid re-encoding this altogether if possible, or otherwise only re-encode a minimal fraction of the total duration. Thus, would like to maximise the use of -vcodec copy.

  


  How can I accomplish this using ffmpeg ?

  


  NOTE : See scenario, and my own rough idea for a possible solution below.

  


  ---

  


  Scenario :

  


  

  • Original video

    

    • Length of 1:00:00

    


    • Has a key frame every 10s

    


    


  


  • Desired cut :

    

    • From 0:01:35 through till the end

    


    


  


  • Attempt #1 :

    

    • Using -ss 0:01:35 -i blah.mp4 -vcodec copy, what results is a file where :

    


    • audio starts at 0:01:30

    


    • video also starts at 0:01:30

    


    • this starts both the audio and the video too early

    


    


  


  • using -i blah.mp4 -ss 0:01:35 -vcodec copy, what results is a file where :

    

    • audio starts at 0:01:35,

    


    • but the video is blank/ black for the first 5 seconds,

      

      • until 0:01:40, when the video starts

      


      


    


    • this starts the audio on time,
but the video starts too late

    


    


  


  


  ---

  


  Rough idea

  


  

  • (1) cut 0:01:30 to 0:01:40

    

    • re-encode this to have new key frames,
including one at the target time of 0:01:35

    


    • then cut this to get the 5 seconds from 0:01:35 through 0:01:40

    


    


  


  • (2) cut 0:01:40 through till the end

    

    • without re-encoding, using -vcodec copy

    


    


  


  • (3) ffmpeg concat the first short clip (the 5 second one)
with the second long clip

  


  


  I know/ can work out the commands for (2) and (3), but am unsure about what commands are needed for (1).

  


• FFMPEG encoded mp4 video don't show video frames but audio is fine [duplicate]

  29 avril 2020, par ark1974

  Trying on converting an mp3 audio and a jpeg image as background image into a mp4 video, video conversion should terminate after it reaches the audio play length.

  



  Here's the ffmpeg commandline. The conversion is successful and encoded mp4 audio is also good, but the image don't seem to appear. Do I have to specify a screen resolution ? Am I making any mistake ? How can I make the command more faster (I can't use -c:a copy as I may be converting other audio formats) ?

  



  ffmpeg -y -loop 1 -framerate 15 -i  "/storage/emulated/0/Download/Kites.jpg" -i "/storage/emulated/0/Download/myaudio.mp3" -c:v libx264 -c:a libmp3lame -shortest "/storage/emulated/0/Download/Out.mp4"