View Full Version : Framerate Conversion
roy_henry
2008-11-18, 22:56
Is there any way to convert a PAL video file to NTSC (slow the video down)? I know it was possible on the XBOX but is it possible in Atlantis? Thanks
Is there any way to convert a PAL video file to NTSC (slow the video down)? I know it was possible on the XBOX but is it possible in Atlantis? Thanks
PAL video is 25fps while NTSC is 29.97fps, so it won't *slow* the video down to use your own words, but why on earth would you want to do that?
roy_henry
2008-11-19, 16:52
From 25fps to 23.976fps, programs/movies recorded on NTSC when transfered to PAL format are sped up by 4% which causes a noticeable and infuriating effect of raising the pitch of every sound. The conversion was a feature of XBMC for Xbox, I'm wondering about doing the same in windows.
jmarshall
2008-11-19, 18:25
Actually, most people don't notice it at all. "Fixing" the problem also has the infuriating effect of being an extremely lossy process (decode audio, resample audio, encode audio back to lossy ac3).
Suffice to say that it's not something that's high on the todo list. You are welcome to assist if you wish. We'd need:
1. An AC3 encoder filter.
2. A resampling filter that handles 23.976->25fps conversion.
3. Code to override the framerate speed.
Cheers,
Jonathan