Recherche avancée

Sur d’autres sites (7191)

• Audio/Video drop when merging 3 FFmpeg commands which includes scale, pad, filter complex

  21 novembre 2018, par Mayank

  I am trying to scale 2 videos to h=240 resolution keeping the same aspect ration. Then I am merging the audio and video of these 2 videos to form a single mp4 file. I have 3 commands in total and the final result is good.

  However, I want to combine these 3 commands and get the same result in one single command. Can someone please help me in combing these commands ? Thanks in advance.

  First Command :

  ffmpeg -i 01_v.mp4 -vf "[0]scale=-1:240[scaled_240]; [scaled_240]pad=width=320:height=240:x=(320-in_w)/2:y=(240-in_h)/2:color=black" -preset ultrafast -y -r pal "1_v.mp4"

  Second Command :

  ffmpeg -i 02_v.mp4 -vf "[0]scale=-1:240[scaled_240]; [scaled_240]pad=width=320:height=240:x=(320-in_w)/2:y=(240-in_h)/2:color=black" -preset ultrafast -y -r pal "2_v.mp4"

  Third Command :

  ffmpeg -i 1_a.opus -i 2_a.opus -itsoffset 0.024181 -i 1_v.mp4 -itsoffset 0.113192 -i 2_v.mp4 -filter_complex "[1:a]adelay=15726.168|15726.168[a1]; [0:a][a1]amix; [3:v]trim=0:15.726168,geq=0:128:128[silence]; [3:v]fifo[3v]; [silence][3v]concat[3_v_silence]; [2:v]fifo[2v]; [2v][3_v_silence]hstack[out_v]; [out_v]pad=width=640:height=480:x=(640-in_w)/2:y=(480-in_h)/2:color=black" -crf 40 -preset ultrafast -y -r pal "out.mp4"

  I have tried to combine the above 3 commands and formed a single command. However, the result is not good with muted audio for few seconds in the middle of playback, also the 2nd video gets over few seconds earlier. Hence ending up in messing up the audio/video sync.

  This is my single command which doesn’t produce the desired result :

  ffmpeg -i 1_a.opus -i 2_a.opus -itsoffset 0.024181 -i 01_v.webm -itsoffset 0.113192 -i 02_v.webm -filter_complex "[1:a]adelay=15726.168|15726.168[a1]; [0:a][a1]amix; [3:v]trim=0:15.726168,geq=0:128:128[silence]; [3:v]fifo[3v]; [silence][3v]concat[3_v_silence]; [2:v]scale=-1:240[2v_scaled_240]; [2v_scaled_240]pad=width=320:height=240:x=(320-in_w)/2:y=(240-in_h)/2:color=black[2v_padded]; [3_v_silence]scale=-1:240[3v_scaled_240]; [3v_scaled_240]pad=width=320:height=240:x=(320-in_w)/2:y=(240-in_h)/2:color=black[3v_padded]; [2v_padded]fifo[2v]; [2v][3v_padded]hstack[out_v]; [out_v]pad=width=640:height=480:x=(640-in_w)/2:y=(480-in_h)/2:color=black" -crf 40 -preset ultrafast -y -r pal out.mp4

• scaling a video captured in portrait mode using FFMPEG

  24 octobre 2016, par Ahmed Mujtaba

  I’m trying to rotate a video on my android app using FFMPEG and then uploading it to the server. The following command does the job for me :

  -y -noautorotate -i inputPath -vf transpose=1,scale=360:640,setsar=1 -metadata:s:v rotate=0

  The aspect ratio of the original video is 16:9. I’m trying to maintain the aspect ratio after rotation so I add padding on either side of the video to scale it properly with the following command :

  -y -noautorotate -i inputPath -vf transpose=1,scale=iw*min(360/iw\,640/ih):ih*min(360/iw\,640/ih),pad=640:360:(360-iw)/2:(640-ih)/2,setsar=1 -metadata:s:v rotate=0

  The video scales perfectly on the website but now the issue is that I can see the black bit when I play it on the android app which I don’t want. I don’t mind the black bits when I play the video on the website but on the app, it looks terrible. The container of the video on the app has height "280dp" and width of "380dp". How can I scale the video so the black sides don’t show when I play a video on the app.
  Any solutions/suggestions ?

  This is what the video looks like when I play on the website :

  

  This is what it looks like on the app

  

• ffmpeg : mix audio and video of different length

  24 octobre 2016, par user3445678

  I have 2 files : 1 video file (without sound) - length 6 seconds, 1 audio - length 10 seconds.
  Both audio and video contains same conversation, but audio starts 4 seconds earlier and after that was started video.

  [----------] audio
  
      [------] video

  So, I want to mix them together to video file with length 10 seconds where first 4 seconds black screen with audio then goes real video and audio.

  [====------] audio+video (where '=' is black screen)

  I hope my description was clear enough ).
  How can I do this with ffmpeg or gstreamer ?