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• swscale/output : Add rgba64/rgb48/bgra64/bgr48 output functions with full chroma inter...

  17 juin 2015, par Michael Niedermayer

  swscale/output : Add rgba64/rgb48/bgra64/bgr48 output functions with full chroma interpolation
  Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libswscale/output.c
  • [DH] libswscale/utils.c
  • [DH] tests/ref/fate/filter-pixfmts-scale

• Android : How to make camera capture video only of preview size and not full screen ?

  13 décembre 2017, par Ashutosh Tiwari

  I am working on an app that needs to capture square videos just like Instagram. I used many libraries for the purpose but none helped to capture the video itself in square size. I can make the preview look like square but not the recorded video. For that I have to use FFMPEG library for cropping the video after it has been captured. But this process takes too long for 1 minute videos even with 480p video capture quality. Someone please guide me to achieve this task.

  Libraries that I have used are :
  https://github.com/natario1/CameraView for cameraView and http://writingminds.github.io/ffmpeg-android-java/ for using ffmpeg.

  Commands that I have tried for ffmpeg cropping operation are :

  command = new String[]{"-y",
  
                  "-f",
  
                  "concat",
  
                  "-safe",
  
                  "0",
  
                  "-i",
  
                  "" + sdCardPathFile,
  
                  "-c:v",
  
                  "libx264",
  
                  "-vf",
  
                  "crop=" + getVideoResolution(),
  
                  "-preset",
  
                  "ultrafast",
  
                  "-qscale",
  
                  "0",
  
                  "-crf",
  
                  "28",
  
                  "-c:a",
  
                  "copy",
  
                  "-flags",
  
                  "+global_header",
  
                  "" + joinedVideoFile.getAbsolutePath()
  
          };
  
  
  
  
  
  
  
  
  
  String[] joinCommand = new String[]{
  
                  "-y",
  
                  "-f",
  
                  "concat",
  
                  "-safe",
  
                  "0",
  
                  "-i",
  
                  "" + sdCardPathFile,
  
                  "-filter:v",
  
                  "crop=480:480",
  
                  "-preset",
  
                  "superfast",
  
                  "-c:a",
  
                  "copy",
  
                  "" + joinedVideoFile.getAbsolutePath()
  
          };

• Feed output of one filter to the input of one filter multiple times with ffmpeg

  27 août 2021, par kentcdodds

  I have the following ffmpeg commands to create a podcast episode :

  


  # remove all silence at start and end of the audio files
ffmpeg -i call.mp3 -af silenceremove=1:0:-50dB call1.mp3
ffmpeg -i response.mp3 -af silenceremove=1:0:-50dB response1.mp3

# remove silence longer than 1 second anywhere within the audio files
ffmpeg -i call1.mp3 -af silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-50dB call2.mp3
ffmpeg -i response1.mp3 -af silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-50dB response2.mp3

# normalize audio files
ffmpeg -i call2.mp3 -af loudnorm=I=-16:LRA=11:TP=0.0 call3.mp3
ffmpeg -i response2.mp3 -af loudnorm=I=-16:LRA=11:TP=0.0 response3.mp3

# cross fade audio files with intro/interstitial/outro
ffmpeg -i intro.mp3 -i call3.mp3 -i interstitial.mp3 -i response3.mp3 -i outro.mp3
  -filter_complex "[0][1]acrossfade=d=1:c2=nofade[a01];
                   [a01][2]acrossfade=d=1:c1=nofade[a02];
                   [a02][3]acrossfade=d=1:c2=nofade[a03];
                   [a03][4]acrossfade=d=1:c1=nofade"
  output.mp3


  


  While this "works" fine, I can't help but feel like it would be more efficient to do this all in one ffmpeg command. Based on what I found online this should be possible, but I don't understand the syntax well enough to know how to make it work. Here's what I tried :

  


  ffmpeg -i intro.mp3 -i call.mp3 -i interstitial.mp3 -i response.mp3 -i outro.mp3
       -af [1]silenceremove=1:0:-50dB[trimmedCall]
       -af [3]silenceremove=1:0:-50dB[trimmedResponse]
       -af [trimmedCall]silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-50dB[noSilenceCall]
       -af [trimmedResponse]silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-50dB[noSilenceResponse]
       -af [noSilenceCall]loudnorm=I=-16:LRA=11:TP=0.0[call]
       -af [noSilenceResponse]loudnorm=I=-16:LRA=11:TP=0.0[response]
      -filter_complex "[0][call]acrossfade=d=1:c2=nofade[a01];
                       [a01][2]acrossfade=d=1:c1=nofade[a02];
                       [a02][response]acrossfade=d=1:c2=nofade[a03];
                       [a03][4]acrossfade=d=1:c1=nofade"
  output.mp3


  


  But I have a feeling I have a fundamental misunderstanding of this because I got this error which I don't understand :

  


  Stream specifier 'call' in filtergraph description 
[0][call]acrossfade=d=1:c2=nofade[a01];
[a01][2]acrossfade=d=1:c1=nofade[a02];
[a02][response]acrossfade=d=1:c2=nofade[a03];
[a03][4]acrossfade=d=1:c1=nofade
       matches no streams.


  


  For added context, I'm running all these commands through @ffmpeg/ffmpeg so that last command actually looks like this (in JavaScript) :

  


  await ffmpeg.run(
  '-i', 'intro.mp3',
  '-i', 'call.mp3',
  '-i', 'interstitial.mp3',
  '-i', 'response.mp3',
  '-i', 'outro.mp3',
  '-af', '[1]silenceremove=1:0:-50dB[trimmedCall]',
  '-af', '[3]silenceremove=1:0:-50dB[trimmedResponse]',
  '-af', '[trimmedCall]silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-50dB[noSilenceCall]',
  '-af', '[trimmedResponse]silenceremove=stop_periods=-1:stop_duration=1:stop_threshold=-50dB[noSilenceResponse]',
  '-af', '[noSilenceCall]loudnorm=I=-16:LRA=11:TP=0.0[call]',
  '-af', '[noSilenceResponse]loudnorm=I=-16:LRA=11:TP=0.0[response]',
  '-filter_complex', `
[0][call]acrossfade=d=1:c2=nofade[a01];
[a01][2]acrossfade=d=1:c1=nofade[a02];
[a02][response]acrossfade=d=1:c2=nofade[a03];
[a03][4]acrossfade=d=1:c1=nofade
  `,
  'output.mp3',
)