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• Audio clicks / cracklings with ffmpeg audio recording on mac os

  15 février 2023, par Specimen

  I'm having audio clicks on my ffmpeg audio recordings. If I record with OBS for example, the audio comes out just fine. This is what I put in the terminal :

  


  ffmpeg -f avfoundation -i ":0" test.mp3


  


  where 0 is my Soundflower audio device, which I found using ffmpeg -f avfoundation -list_devices true -i "", which returns :

  


  AVFoundation audio devices:
[0] Soundflower (2ch)


  


  Soundflower, my speakers, and the ffmpeg recording are all set at 48kHz.
There is another thread that states that this may be an issue with ffmpeg version 4.3, and to try to downgrade to 4.2 ; I tried to google how to downgrade on brew, but didn't find anything.

  


• lavfi/fifo : fix flushing when using request_samples

  4 août 2013, par Anton Khirnov

  lavfi/fifo : fix flushing when using request_samples
  If any samples are still buffered when request_frame returns EOF, they
  
  won’t be returned currently.
  

  • [DH] libavfilter/fifo.c

• ffmpeg : improving MP4 to webm ogg conversions

  14 juillet 2017, par Randy

  (Edited to include some of the things I’ve tried)

  I’m a musician, and occasional web coder. I’ve been using video editing software (old version of Roxio Videowave from 2011) to build promotional videos from clips of some of my performances, and I’d like to put some of them on my own web pages in HTML5 video format. So that currently means I need MP4, WEBM, and OGG conversions. Fortunately the editing software churns out some very nice MP4 (H264) files, and has plenty of options for doing so. I purposely output the output size about 2X the likely display size, in hopes of offering more detail for better conversions. Specifically, the video output was AVC/H.264, 800 x 450, 30fps, variable bit rate, but with 600000 as a base line (that was the default for this setting anyway).

  Now I’m nowhere near expert at this stuff, and I probably left out some important data. But bottom line, the resulting MP4 looked very good. Unfortunately, to put it on my own web page means at least converting to WEBM and OGG formats. It would be nice if all browsers just supported MP4, but then there would be licensing fees, so conversions are needed. Sadly, I’ve been wasting days now trying to do this with ffmpeg. Its easy to do, its doing it WELL that is a mystery to me. Just letting ffmpeg work using its defaults (meaning I just specify an input and output file) results in pretty terrible video. But I’ve also tried most of the settings for better quality available, and the resulting conversions are nowhere near as good as youtube’s conversions.

  Based on the info about my original MP4 file, can someone suggest some better settings for ffmpeg conversions to WEBM and OGG ? Am I going about this all wrong ? The best I’ve done so far was with a string like this, which specified a high quality and a fairly robust bit rate...

  ffmpeg -i input-file.mp4 -c:v libvpx -crf 10 -b:v 1M -c:a libvorbis output-file.webm

  That was much better than the default settings, but still nowhere near the quality of YOUTUBE conversions. In my resulting WEBM video, you can pretty plainly see how the picture degrades, and will snap into focus every few seconds when a "key frame" comes up. These artifacts should not be so obvious. Thanks for any help.