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why would you want to do that? You would get jerky animation due to dropped frames, because there would be no other way for your player to achieve this rate than to leave out one frame every second (pal-dvds are mostly 25fps and all frames progressive). A true frame-rate conversion would require interlacing every few frames to get the animation as smooth as before, I highly doubt any player could do this in realtime.
 

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Film PAL DVDs are upconverted from 24 fps to 25 fps by simple speeding up of the movie. It means that all film PAL DVDs are 4% shorter than their NTSC equivalents and that their soundtracks have little bit higher pitch. WinDVD version 3 has the option to slowing down (or speeding up) playback by little steps. So 0.95x speed should give the right speed. However the problem is with the sound. It is not possible (obviously) to use DD or DTS S/PDIF out but instead the internal sound decoding engine must be used.


Tomas
 

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i'm with you Ray ... i'm looking for the day that dvd player (soft or desktop) would slow down PAL movie to 24fps


heard that some musicians could not stand the music on PAL DVD because of the speed up!


note that NTSC is not so bad since DVD or encoded at 23.976fps to be played with the 3:2 pulldown technic ... that means just a bit slower that 24fps ... nothing compare to the problem with PAL DVD


ps

i did an exercise some while ago ... i converted a PAL VCD to NTSC:

converted 25fps mpeg video to 25fps avi (FlaskMpeg)

patch the avi to make it 23.976 fps

re-converted the avi to mpeg-1 video

converted mpeg audio to wav

converted down the audio 4.096% slower (with SoundForge)

mux back the mpeg-1 video and audio, burned it and voîlÃ*

...the VCD was The Phantom Menace and got something like 12 mins more of movie!
 

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Discussion Starter · #5 ·
Thanks for the replies!


Yes, it's mainly a sound issue. Playing films at 25fps raises the pitch by almost exactly a semi-tone. This is pretty much the limit that you can get away with; if you raise the pitch by another semi-tone, most voices start to suffer from "chipmunk syndrome". Some voices seem more susceptible than others. In any PAL version of THE MALTESE FALCON, there are occasions when Bogart sounds too much like Bugs Bunny. :)


I'll take a look at WinDVD 3, and see how it works...
 

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Does that speed problem occure only with HTPC playback of DVDs or also with normal DVD players?


I don't understand all the "wrong speed process" and on which material does it happen. Is it for all Pal films (US and Europeans based) ?


I am planning to build a high quality HTPC to mostly view Pal filmDVD and 4% speed increase look terrible.
 

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Ok, what way is there to tell what the frame rate is during playing? im currently in Europe but will be home in a couple weeks and im bring some Pal dvd's with me. but i have a sampo tv, which does both pal and ntsc, switches according to the signal, so i'll have to let you guys know what happens
 

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For PAL DVDs the frame rate is always 25 FPS. This is how was PAL system defined (actually 50 half interlaced frames per second). However most of the movies are shot in 24 FPS (not all, European movies are sometimes shot in 25 FPS => no speed up needed). To convert 24 FPS film to 25 FPS PAL DVD speed up is needed. That results to faster motion (not noticable) and higher pitch of the sound.


Tomas
 

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Discussion Starter · #9 ·
WinDVD turned out to be a bust. It can slow the playback rate down to 95% (or a bunch of other speeds), but it shifts the pitch of the audio back up to the "wrong" 25fps rate. Very clever, but not what I want.


Dang, you'd think there'd be a simple way of doing this...
 

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Quote:
Originally posted by Ray Gunn
WinDVD turned out to be a bust. It can slow the playback rate down to 95% (or a bunch of other speeds), but it shifts the pitch of the audio back up to the "wrong" 25fps rate. Very clever, but not what I want.


Dang, you'd think there'd be a simple way of doing this...
Sounds like something that could be added to Zoom Player - making a graph that used the WinDVD video decoder to do the video at 95% speed and another audio decoder at 95% speed but without the overly helpful automatic pitch "correction".
 

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When I play a disc in PowerDVD and display the disc information it show this:


Video Attribute :

Video compression mode : MPEG-2

TV system : 625/50 (PAL)

Aspect Ratio : 16:9

Display Mode : Only Letterbox

Source picture resolution : 720x576 (625/50)

Frame Rate : 25.00

Source picture letterboxed : Not letterboxed

Bitrate : 9.80Mbps


I tried it with 72Hz and 75Hz and it showed the same.
 

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Hi Guys & Gals,


Those of you who like Jackie Chan films will be happy to hear that Hong Kong Legends in the UK has recently transferred a number of them to Pal DVD with good results. I'm saying this as I got one, and boy, if you thought he moved quick in NTSC, try to follow the action in Pal! ;)


You've got it right that Pal bumps the tone up too high in some instances. Speeding up can also remove some critical suspense or pacing in dramatic interactions between characters.


Recently I compared the Pal and NTSC versions of Vertigo: while the color saturation and detail were, to my surprise, superior in the Pal version, there was a problem with the sound and the pacing.


Jimmy Stewart's voice lost its throaty gurgling midwestern accent in the Pal version (a French friend said he couldn't tell the difference) and the fellow in the bookstore sounded far less yiddish in intonation in the Pal version (although he was supposed to be French or something).


More importantly perhaps, when actors mark a pause to bring attention or convey a sense of suspense, the impression is thwarted by speeding up the reel - without being consciously aware of it, we are actually sensitive to timing within fractions of a second, as the dramatic impact can be changed by faster pacing. Actors have always known this, but obviously not all viewers or video format inventors are aware of it.


Lastly, any tweak to an HTPC or other device which might allow to slow Pal back down to 24fps while resynching the sound, should do so selectively: nowadays many subjects in Europe are purposely filmed in 25fps to avoid this speeding up during transfer to Pal.


Cheers,
 

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I have one question concerning this: As I live in PAL-land, I mostly own PAL-DVDs but thanks to the friendly import store nearby I got ahold of some NTSC discs as well. Now can anyone tell me why some movies are exactly the same length in PAL and NTSC? They´re supposed to run at a higher speed, yet I cannot even tell the difference on the audio tracks when I compare them side by side (most PAL-DVDs in Germany also include the english audio track). Granted, some differ wildly, but in those cases the extras on the DVDs differ as well (T2 Ultimate Edition does not have the ability to play the "normal" version in Germany as well as the hidden extra chapters, they are simply missing although the menu graphics are still on the disc).
 
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