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• How do unwrap fisheye and overlap fisheye lens with ffmpeg ? [closed]

  10 juillet 2023, par MrWm

  I am using an insta 360 x3 and would like to automate exporting videos without using their studio tools on Linux.

  


  Here's a screencap of a video format in the camera :

  


  Insta360 x3 camera screenshot

  


  ---

  


  I am using ffmpeg to unwrap the video feed with the following command : (taken from here)

  


  ffmpeg -y -i input.lrv -vf v360=dfisheye:e:yaw=-90 -c:v libx265 -b:v 40000k -bufsize 5000k -preset ultrafast -c:a copy -t 10 test.mkv


  


  The command works, and does a decent job, but one of the lens has a higher field of view with a fuzzy outline. This results in the following image :

  


  Image of Insta360 x3 camera screenshot after ffmpeg command

  


  ---

  


  Is there a way to change the ffmpeg command to either overlap both lenses by a couple pixels to remove the fuzz, or crop out the overlapping field of view ?

  


• Should I use the MP3 or AAC codec for a .mp4 file ?

  4 février 2023, par Justin Jenkins

  We have an encoding process in place using ffmpeg on Mac OS X. This process will take a source video and a couple files from that : .m3u8 video, .mp4 video and .mp3 audio file.

  



  By default we've used the video from our m3u8 process which is a h264 (via libx264) video with AAC (via libfaac) audio.

  



  We are mostly using these videos on mobile devices (hence the m3u8 files) but we also use the .mp4 files for Android, Windows Phone, etc. More and more we also need to offer these same videos on the web via either a flash player or HTML5 player.

  



  Therefore, we'd like to have the best audio/video codec combo for all these uses ... where I'm confused is to what is "standard" for a .mp4 file ?

  



  If the .mp4 uses the mp3 codec then it plays just fine everywhere but QuickTime, in QuickTime the video plays but there is not audio (works just fine in VLC player tho.)

  



  I've been told it's due to how QuickTime uses file extensions to assume information about the video instead of trying to actually get the codec data from the file ? This does make some sense, if we encode the same file but use AAC for the audio codec then it works just fine in QuickTime.

  



  So --- what's the "correct" or "ideal" audio/video codec combo --- is it best and safe to use AAC (i.e. will it work on a broad range of devices) even though it's not a "free" codec ?

  


• Should I use the MP3 or AAC codec for a .mp4 file ?

  8 novembre 2014, par Justin Jenkins

  We have an encoding process in place using ffmpeg on Mac OS X. This process will take a source video and a couple files from that : .m3u8 video, .mp4 video and .mp3 audio file.

  By default we’ve used the video from our m3u8 process which is a h264 (via libx264) video with AAC (via libfaac) audio.

  We are mostly using these videos on mobile devices (hence the m3u8 files) but we also use the .mp4 files for Android, Windows Phone, etc. More and more we also need to offer these same videos on the web via either a flash player or HTML5 player.

  Therefore, we’d like to have the best audio/video codec combo for all these uses ... where I’m confused is to what is "standard" for a .mp4 file ?

  If the .mp4 uses the mp3 codec then it plays just fine everywhere but QuickTime, in QuickTime the video plays but there is not audio (works just fine in VLC player tho.)

  I’ve been told it’s due to how QuickTime uses file extensions to assume information about the video instead of trying to actually get the codec data from the file ? This does make some sense, if we encode the same file but use AAC for the audio codec then it works just fine in QuickTime.

  So --- what’s the "correct" or "ideal" audio/video codec combo --- is it best and safe to use AAC (i.e. will it work on a broad range of devices) even though it’s not a "free" codec ?