Forcing Pal dvd to run @ 30fps to match nstc dvd? for international movie night
Zeropoint1
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I'd like a little advice please about NTSC & PAL DVD's.
Basically I'm planning a "movie night" with friends in America where we all play the movie at the same time and then comment, make fun and have a fun discussion using Facebook chat. I don't have enough bandwidth for webcam chat.
But my question is - As I will be playing a PAL DVD running at 25 fps and they will be running NTSC at 30 fps I will eventually run ahead of them by several minutes. Is there a way for me to speed up my movie without it becoming to annoying?
If it helps I have a PC, PS3 and HD DVD player (Toshiba HD EP 30KB) if one of those can be forced into speeding up PAL. I know the easiest solution would be for me to play a R1 DVD, but that adds extra expense.
Thanks in advance.
Basically I'm planning a "movie night" with friends in America where we all play the movie at the same time and then comment, make fun and have a fun discussion using Facebook chat. I don't have enough bandwidth for webcam chat.
But my question is - As I will be playing a PAL DVD running at 25 fps and they will be running NTSC at 30 fps I will eventually run ahead of them by several minutes. Is there a way for me to speed up my movie without it becoming to annoying?
If it helps I have a PC, PS3 and HD DVD player (Toshiba HD EP 30KB) if one of those can be forced into speeding up PAL. I know the easiest solution would be for me to play a R1 DVD, but that adds extra expense.
Thanks in advance.
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Even though your US friends are watching at 30fps, they will be "doubling up" on some frames so the film will actual show at 24fps.
When I read back what I'd written it didn't seem right but I couldn't spot what was wrong - it was slowing down as you say not speeding up.
Just one more question - Would playing a Blu-Ray or HD DVD set to 24 fps work on my Viera which makes no mention of 24 fps support or would that just stutter and judder?
surely if a films 90 minutes long.... then its 90 minutes long wherever in the world you watch it?
So every second the PAL system "gains" 5 frames of video, so every 5 seconds we advance a further second more than we should. And add those extra seconds over a 90 minute film and it soon adds up to a shorter length than the NTSC system.
Apperantly some people can detect this speeding up and it makes some soundtracks sound "wrong"
A little late night reading - http://en.wikipedia.org/wiki/PAL#PAL_vs._NTSC
Movies are shot at 24 frames per second. UK TV uses 25 frames per second. So rather than do any complex standards conversion the DVD makers simply speed up the movie to 25 frames per second. Hoping no-one notices the 4% or so increase in speed.
In the US they use 30 frames per second for TV so speeding up is not an option really. So they have to use a load of clever trickery to invent the "missing" 6 frames per second. So in the US their disks run at the correct speed.
I think the night reading should be you.
In both cases if the dvd is mastered from film material it starts off at 24fps. The PAL version is digitised to 25fps (a relatively easy thing to do). The NTSC version has it's frame rate adjusted to 29.97 fps not by speeding it up but by adding extra invented frames in a process called pulldown. The ntsc frame rate was reduced to 29.97 from 30 to incorporate colour.
A UK DVD using 576i 25fps. (720 x 576 pixels). A 1 hour movie will have 90,000 frames. If you speed it up to 30fps it will play back in 50 mins. And look a bit like a Charlie Chaplin movie
The NTSC 1HR DVD using 480i 29.97fps (720 x 480 pixels) has 107,892 frames and will play back in the same time
In fact DVD's are not really PAL at all they use the same frame rate but strictly speaking PAL refers to the phase reversal of the colour component (Phase alternate line) so only applies to a transmitted analogue signal
I think you owe the poster who made the obvious point an apology.
As I understand it, the MPEG stream on an "NTSC" DVD is encoded at 24 fps, and on a "PAL" DVD at 25 fps. So there is an inherent difference in playback time, regardless of the ultimate NTSC frame rate.
No, on an "NTSC" DVD, the framerate is encoded as 29.97fps.
On a blu-ray it will usually be encoded as 24fps.
If you played a blu-ray in the UK and your friends did the same in the states, you'd stay in sync as Blu-ray as standard when not outputting 24fps if the TV can't handle it will output at 60fps.
And for those of you with perfect pitch, the 4% speed-up of film transfers to PAL DVD equates to about a semitone increase in pitch.
This site seems to agree with me. See Table 3 towards the end of the page.
This, I agree with.
ETA: I see you've added a bit to your post which shows that you agree that "PAL" DVDs run faster than "NTSC" DVDs (when both are derived from a film source), which was the main point of contention. According to table 1 of the reference I gave, "NTSC" DVDs can also be encoded at 23.976 fps or 29.97 fps for "DVD specials", so my claim was not universally true.
When I play an NTSC DVD on my tv through Blu Ray player, press info I get 1920x1080@24Hz.
An exaple of running times as I have both:
Batman Pal: 122mins
Batman NTSC: 126mins
Doesn't really tell us much about runtimes though!
ETA: But now you have. Why do people keep catching me out by adding bits!
Your TV is lying. If it was 24fps by far the majority of UK tv's will not work at 24fps. Only later HD TV's designed to allow bluray playback at native frame rate will handle 24p. A few dvd players will output a pseudo pal signal from ntsc standard discs but that's not whats on the disc (it's always 29.97 fps though the resolution can vary within limits specified by the dvd standards). Your bluray must do simiular and it's confusing your tv's video reporting and changing the playback duration. If you played the ntsc disc on a ntsc player it would take the same time. (What's it say on the package ?)
If you multiply 720 x 576 x 25 to get the pixel data rate for a PAL dvd and 720 x 480 x 30 for ntsc one it's no coincidence they give the same answer.
I can't play ntsc discs on my bluray it's region coded but i can on my Denon DVD player.
You seem to be in denial! The playback duration is different. His TV hasn't somehow tricked the player.
Perhaps I should of also added that if I turn off 24fps then NTSC DVD is output at 60Hz.
You are in denial. There are no ntsc dvd's that use other than 29.97 fps if they used a different frame rate they would not be ntsc and they would be totally unplayable in the US where all SD TV's can only handle 30fps or higher and dvd players will not play PAL dvds.
There are two horizontal resolutions 704 (compatible with ATSC SD digital terrestrial transmission and the advanced atsc using 720 (dvd's generally always are 720)
Format : MPEG-PS
File size : 1 024 MiB
Duration : 20mn 32s
Overall bit rate : 6 968 Kbps
Video
ID : 224 (0xE0)
Format : MPEG Video
Format version : Version 2
Format profile : Main@Main
Format settings, Matrix : Default
Duration : 20mn 32s
Bit rate mode : Variable
Bit rate : 6 243 Kbps
Nominal bit rate : 7 800 Kbps
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 2.35
Frame rate : 29.970 fps
Standard : NTSC
Colorimetry : 4:2:0
Bits/(Pixel*Frame) : 0.603
Stream size : 918 MiB (90%)
Audio
ID : 129 (0x81)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 20mn 32s
Bit rate mode : Constant
Bit rate : 448 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Surround: L R, LFE
Sampling rate : 48.0 KHz
Video delay : -71ms
Stream size : 65.8 MiB (6%)
Text
ID : 224 (0xE0)-DVD-1
Format : EIA-608
MuxingMode : MPEG Video / DVD-Video
MuxingMode_MoreInfo : Muxed in Video #1
Menu
Format : DVD-Video
And you are completely wrong about the running times of "PAL" DVDs and "NTSC" DVDs of the same film being the same. As several people have now told you, "PAL" DVDs run about 4% faster.
Films are 24 Frames Per Sec
PAL dvds (and European broadcast tv) usually play films ate 25 fps, slightly faster.
Showing films on broadcast (& dvd) NTSC 30fps has long been a problem, and ideally would be dealt with by proper standards conversion, but often is by 3:2 pulldown.
http://www.moviola.com/book/export/html/269
For NTSC dvds the film is stored as 24fps on the dvd. The dvd player converts it to 29.97 to display on the screen by duplicating some frames. The running time will be as if it was shown at 24fps.
For PAL, the film is speeded up by 4% and stored on the dvd at 25fps and is sent to the tv at 25fps. Running time will be 4% shorter than the NTSC version.
Post 17 is the analysis of the actual content of a ntsc DVD read as data direct from the disc, not the output of a player.
I can do the same for a region 2 PAL disc if you wan't
Your understanding is incorrect. The same data can be input to a video editor like premier pro which will show each and every frame if you want further proof :eek:
It would be pretty stupid to build this process into each and every DVD player rather than doing it once with pro kit before creating the DVD.
Why does not the poster with two versions of the same film simply post what the posted running time on each is. Not the pseudo actual run time of playing a ntsc disc in a bluray player. The two figures will be the actual run time of each when played on a DVD player designed to playback the content
DV camcorders from the US record at 29.97fps, from the UK they record at 25fps. The former is directly burnable to ntsc DVD without frame rate conversion, the latter the same to a PAL DVD.
I already posted the running times of Batman which are:
Batman Pal: 122mins
Batman NTSC: 126mins
Another is Transformers:
Pal: 137mins
NTSC: 143mins
A way that the OP could get around this issue which I think may work if they want to go through the effort is to use DVD shrink and make another copy and change the output to NTSC.
Any change in duration is then purely down to the process used to increase the number of frames in the original mastering process for the ntsc version. If the number of frames/30 in the ntsc version is not the same as the number of frames/25 in the PAL version they can not be made to run in synch without a very minor speed change. Increasing playback of the PAL version to 30fps certainly won't match playback in fact it will do exactly the opposite.
By Your figures BATMAN - pal will have 183,000 frames increasing this to playback at 30fps will give a playback time of 101 minutes.
DVDshrink will not change PAL to NTSC or vice versa. all it can do is reduce the bitrate to make the files smaller. It has no effect on run time. In any case it won't work on most CSS protected content.
Comversion of PAL to ntsc is far from an easy process and the results are generally not very good. I know because I have converted UK PAL wedding footage to NTSC to send to relations in the US. It takes a long time to resample to 720 x 480 and 29.97 fps. (Adobe After Effects is about the best at this of the software I have used).
Most PAL R2 DVD's are encoded at 25FPS progressive. Usually this is achieved by speeding up the original film frame rate of 24fps by 4%. The audio is then pitch corrected.
Also, be wary of content changes. A prime example from memory is Austin Powers.
Some major differences there. It's easy to be seeing 2 different versions of the same film.
This is a great site to check differences in releases http://www.dvdcompare.net/index.php
Can you give a few examples the few that I have all have 29.97 fps when reading the actual data ?
Seeing how I've been backing up my DVD collection over the past couple of months (think I'm half way through now) I can absolutely give you a few examples from ones I encountered only last night.
The Haunting
The Crow
The Crow: Salvation
T2: Ultimate Edition
Galaxy Quest
Software players will always show the running framerate taking flags into account. If you're checking on the PC I recommend grabbing a copy of Virtualdubmod (http://www.videohelp.com/tools/VirtualdubMOD) and just dropping a VOB from the main movie in and then looking at the framerate in there.