how to enable 24p 24hz on HD TVs with radeon and radeonhd ?

[RealNC]

I also did a read-up on this and it seems Blue-Ray discs use 24p (true 24Hz of Hollywood movies) which does work perfectly with multiples of 24Hz, while HD-DVD uses 23.976p (based on NTSC) which does not work perfectly with multiples of 24Hz...

Yes, it's confusing

The point that stands out here though is that movies that are shot on film use exactly 24FPS, not 23.976FPS since that makes zero sense for film.

[bridgman]

Actually I think BluRay allows both 23.976 and 24 Hz encoding, and the player outputs whatever rate was used when encoding. Anecdotally it seems like most BluRay disks are encoded at 23.976 -- yeah, they play the 24fps film at 23.976 so it's actually running a tiny bit slow. Not as bad as playing a film at 25 Hz for PAL TV, of course

Movies shot on film are usually 24 fps, although apparently there are even some film cameras which will shoot at 23.976 for cases where the film is being shot "for TV". Now that more movies are being shot directly in HD video the original rate can be either 23.976 or 24 depending on which way the camera is set.

I had been told that HD-DVD didn't actually support 24p natively at all -- that films were encoded at 30p (29.97) but with a flag to indicate which frames could be dropped to get 24p (23.976).

The scary thing is that I can find posts which contradict pretty much everything I said above, but if I filtered based on what OTHER things the poster got right the above seems to be "most likely to be correct". You rolls your dice...

[bugmenot3]

Will it ever be possible to select 24p in the gnome randr application? Tried to connect my computer via HDMI with my 24p capable TV and only could select 60p @1920x1080. Fedora 14 AMD64 and RS880 with a Samsung TV.

[Kano]

@bridgman

When you encode mpeg2 telecine (dvd) with mencoder it is the same, a flag shows mplayer then that inverse telecine can be used. That's nothing special to hd dvd. Basically those extra frames will not require much space as they are identical to the one before. Should be easy to detect even without a flag in theory...

When you look at bluray movies a few are not 23.976, mainly cheap productions. Some very rare ones are 25 fps like the millenium triology.

[agd5f]

Will it ever be possible to select 24p in the gnome randr application? Tried to connect my computer via HDMI with my 24p capable TV and only could select 60p @1920x1080. Fedora 14 AMD64 and RS880 with a Samsung TV.

You'll either have to manually add the mode using xrandr, or fix the kms or xorg edid parsers to deal with CEA EDID extension blocks which is where the 24p modes are generally specified.