[FFmpeg-user] Concatenated mpegts segment files

[Tefl Zuren]

​​I've been trying to use ffmpeg to download video from certain websites but always encounter the warning "Non-monotonous DTS in output stream" when downloading. The saved video file won't play correctly beyond a certain point in the file. It appears that the websites use a mpegts container and ffmpeg downloads a long list of these files. After the first group downloads, and a new group ​begins, the warnings begin to appear. Another user stated "Some playlists contain a sequence of separately produced MPEG-TS files. So, there's a timestamp reset when each new segment is received. At this point, the timestamp code in libavformat's mux.c simply increments the output timestamp by one when this happens. Unless the timebase resolution is 1/fps, this produces an unsound file." Is there a way in ffmpeg to properly concatenate these? I've been trying to find a fix for over a year and tried various workarounds but nothing works.