Recherche avancée

Sur d’autres sites (15403)

• How to write a filter for ffmpeg that burn subtitles using a subtitle stream directly

  20 mars 2014, par Filimindji

  Let say I have an MKV with a video stream, an audio stream and a subtitles stream.

  I would like to burn this subtitle into my video directly from the subtitle stream.

  so far, this is my command line :

  ffmpeg.exe -i "MyMovie.mkv" -map 0:0 -map 0:1 -vf subtitles=sub.srt out.mkv

  So far so good. But, my subtitles are inside the movie and I need to extract them before. I used this :

  ffmpeg.exe -i "MyMovie.mkv" -f srt sub.srt

  But this operation is too long : 25 sec on my PC for a 2.5Go MKV. I need something faster because I need to start streaming the output to an app as soon as possible. (I did not mentioned the others command line arguments I used to achieve this streaming properly because my question is not about that.)

  I know it is not possible to get the stream directly like this :

  ffmpeg.exe -i "MyMovie.mkv" -map 0:0 -map 0:1 -vf subtitles=[0:s:0] out.mkv

  But this is something I would love.

  edit :

  But I already know this kind of command line do not exist. (But if I'm wrong, please, let me know.)

  Now, I would like to write this kind of filter myself, and compile ffmpeg with it.
  But I have no idea where to start.

  Can anyone help me to start ?

  Thank you

• Ffmpeg burnt in subtitles out of sync when converting to hls

  19 mai 2020, par user1503606

  I have a file that has subtitles burn into it and they are perfectly in sync.

  



  Here is the file. https://983yqbz442.s3.amazonaws.com/little-mermaid-captions.mp4

  



  I run this command to convert to hls and it creates the .ts files and the .vtt files.

  



  ffmpeg -i little-mermaid-captions.mp4 -profile:v baseline -level 3.0 -s 640x360 -start_number 0 -hls_time 10 -hls_list_size 0 -f hls index.m3u8


  



  I also then create a master.m3u8 file in the same folder with the following.

  



  #EXTM3U
#EXT-X-VERSION:3
#EXT-X-INDEPENDENT-SEGMENTS
#EXT-X-STREAM-INF:BANDWIDTH=800000,RESOLUTION=640x360,SUBTITLES="subtitles"
index.m3u8
#EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID="subtitles",NAME="English",DEFAULT=YES,AUTOSELECT=YES,FORCED=NO,LANGUAGE="ENG",URI="index_vtt.m3u8"


  



  Now if I play the master.m3u8 file the subtitles are now out of sync and are about 1 sec to quick. I understand this is probably a setting I am missing through FFmpeg but really stuck on this and would appreciate any insight.

  



  Thanks

  



  More info.

  



  Here is a link to the direct .m3u8 this can be opened in Safari.

  



  https://983yqbz442.s3.amazonaws.com/hlstests/master.m3u8

  



  The generated vtt file is here.

  



  https://983yqbz442.s3.amazonaws.com/hlstests/subs-0.vtt

  



  If you look at the start of the .vtt file you will see this.

  



  WEBVTT

00:06.840 --> 00:10.320
once long ago in the deep blue below


  



  It should start at 00:06.840 but when playing the .m3u8 file in Safari you should see it starts at around 5 seconds not 6 about a second too early.

  


• MP4 to all mobile compatible 3gp

  2 mai 2013, par Susheel Mishra

  I am using FFMPEG for converting mp4 video to 3gp.I want to convert it to low end android phone as well as iphone.I am not concern with quality.Using it on linux server with php.

  I searched but my need is diferent , hence post question.

  thanks