Naive question as a result of the PAL-speedup thread: (1 Viewer)

[MikeSerrano]

PC DVD-ROM a possible solution to PAL speedup?
The way I understand it, a PAL DVD contains all of the individual frames of the original film but instead of playing 24fps, they are sped up to 25fps.
What technological barriers are there to just slowing down the playback of the frames to 24fps? It is already possible to step through each frame using the pause/step feature of every software DVD player ever made. You could then output the video via upconverted HDTV or in native resolution to a multi-sync RGB device (monitor, CRT projector data projector).
The hard part would be the audio. However, now that people are figuring out how to implement real-time multi-channel encoders in software, I'm sure someone could create a chip that could play the 48Khz audio-stream at 46.08Khz and resample to 48Khz on the fly.
What am I not considering?
-Mike
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[TheoGB]

I don't know about this but supposedly a PC DVD-ROM should be able to act like a progressive scan television and player, thus eliminating pulldown from NTSC and making them, resolution aside, the version of choice.
I say supposedly because it doesn't happen on my system. I was slightly underwhelmed by everthing except image quality on my PC monitor using various types of software. On the otherhand, having Seven playing in a tiny window with a commentary on was wayyy cool.
Interesting argument you make, however.
Theo

 

[Jeff Kleist]

It can't eliminate the speedup, because the acceleration occurs during the transfer stage, before compression
Jeff Kleist

 

[Roland Wandinger]

Don't know if it technically would be possible to actually slow down PAL but there are solutions for HTPC to pitch correct them via software. I guess we will see something like that in regular DVD player at some point?

 

[MikeSerrano]

but there are solutions for HTPC to pitch correct them via software

That is exactly what I am looking for!
Roland, do you have any specific details (company names/websites)?
-Mike
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.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o 0o.
void *: Finger to spiritual emptiness underlying everything
.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o0o.o 0o.

 

[Roland Wandinger]

Just yesterday I read something in a German AV magazine about a software which is correcting the pitch. They also said that it is not perfected yet and that one is for the moment better off without it.
I'll check the magazine at home and I'll post if they mention some company names or products.

 

[Roland Wandinger]

The newest version of WinDVD 3.0 from Intervideo Inc. is supposed to have a correction for the speed-up but as they state it degrades the audio considerably!

 

[Vincent Matis]

It can't eliminate the speedup, because the acceleration occurs during the transfer stage, before compression

You sure about that??
I thought that DVD were 24fps.
In case of NTSC a flag ("repeat_first_field") was set on some fields so that were repeated twice ("3:2 pulldown").
In case of PAL, the speedup can be done by the player during the decoding phase, following instructions embedded in the video stream (process sometimes referred to as "2:2 pulldown").
I know it is technically possible to "delay" the speedup until the decoding stage, but I must admit I don't know if it is actually done in "real life".
Vincent
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