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• How we can replace all images with another in video using FFMPEG library ?

  17 juin 2020, par Parth Virani

  Challange

  



  i had search many things on internet for do this above function but still i can't able to make it hear i have attached before video and after video which i want using ffmpeg library

  



  Before Video : https://drive.google.com/file/d/1MIUtuOkw22BiyFTKanDeio-VzYS5vKmn/view?usp=sharing

  



  After Video : https://drive.google.com/file/d/1Vot237PcDPA5BqnLRHlQ1ierYrLIyUj9/view?usp=sharing

  



  keep one thing in mind i only need to change images only the text,effects and sound should be as it as

  


• FFMPEG errors with non-English characters

  1er avril 2021, par Mingli Yang

  When I tried to use the command-line to catch a chrome window with non-English characters such as ¥, or any other 中文页面, an I/O error will occur with the message "Can't find window "¥中文页面。 - Google Chrome", aborting." When the non-English characters are replaced by English ones, the errors will disappear. Environment : Windows 10, ffmpeg version 2021-03-24

  


  This works fine :
ffmpeg -f gdigrab -i title="$ English Page - Google Chrome" -pix_fmt yuv420p grab.mp4

  


  This has errors :
ffmpeg -f gdigrab -i title="¥中文页面。 - Google Chrome" -pix_fmt yuv420p grab.mp4

  


  "Can't find window "¥中文页面。 - Google Chrome", aborting."

  


  Any ideas to solve this ?

  


• Transcode HLS Segments individually using FFMPEG

  27 mai 2013, par rayh

  I am recording a continuous, live stream to a high-bitrate HLS stream. I then want to asynchronously transcode this to different formats/bitrates. I have this working, mostly, except audio artefacts are appearing between each segment (gaps and pops).

  Here is an example ffmpeg command line :

  ffmpeg -threads 1 -nostdin -loglevel verbose \
  
     -nostdin -y -i input.ts -c:a libfdk_aac \
  
     -ac 2 -b:a 64k -y -metadata -vn output.ts

  Inspecting an example sound file shows that there is a gap at the end of the audio :

  

  And the start of the file looks suspiciously attenuated (although this may not be an issue) :

  

  My suspicion is that these artefacts are happening because transcoding are occurring without the context of the stream as a whole.

  Any ideas on how to convince FFMPEG to produce audio that will fit back into a HLS stream ?

  ** UPDATE 1 **

  Here are the start/end of the original segment. As you can see, the start still appears the same, but the end is cleanly ended at 30s. I expect some degree of padding with lossy encoding, but I there is some way that HLS manages to do gapless playback (is this related to iTunes method with custom metadata ?)

  
  

  ** UPDATED 2 **

  So, I converted both the original (128k aac in MPEG2 TS) and the transcoded (64k aac in aac/adts container) to WAV and put the two side-by-side. This is the result :

  
  

  I'm not sure if this is representative of how a client will play it back, but it seems a bit odd that decoding the transcoded one introduces a gap at the start and makes the segment longer. Given they are both lossy encoding, I would have expected padding to be equally present in both (if at all).

  ** UPDATE 3 **

  According to http://en.wikipedia.org/wiki/Gapless_playback - Only a handful of encoders support gapless - for MP3, I've switched to lame in ffmpeg, and the problem, so far, appears to have gone.

  For AAC (see http://en.wikipedia.org/wiki/FAAC), I have tried libfaac (as opposed to libfdk_aac) and it also seems to produce gapless audio. However, the quality of the latter isn't that great and I'd rather use libfdk_aac is possible.