title: Using ffmpeg option -video_track_timescale 25 produces a video with 1k tbn. Why is this?
body: <p>I am recording a live audio stream with an image using this code:</p>
  <pre><code>/usr/bin/ffmpeg -re -loop 1 -framerate 25 -i /var/www/html/slowwmo-images/sjw.png -i rtsp://media.vezer.uk:4444/nimble/audio -vcodec libx264 -profile:v main -video_track_timescale 25 -pix_fmt yuv420p -s 1280x720 -vf fps=25 -acodec aac -af aresample=44100 -f flv /var/www/html/slowwmo-live/live.ts
  </code></pre>
  <p>Why does <code>/usr/bin/ffprobe /var/www/html/slowwmo-live/live.ts</code> show 1k tbn when I need it to be 25?</p>
  <pre><code>Stream #0:0: Video: h264 (Main), yuv420p(progressive), 1280x720 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 1k tbn, 50 tbc
  </code></pre>