Best Blu-ray Movie Deals


Best Blu-ray Movie Deals, See All the Deals »
Top deals | New deals  
 All countries United States United Kingdom Canada Germany France Spain Italy Australia Japan Mexico
Star Trek: Stardate Collection (Blu-ray)
$29.99
17 hrs ago
Shrek: The Ultimate Collection (Blu-ray)
$17.99
15 hrs ago
Zombie 4K (Blu-ray)
$36.49
 
Doctor Sleep 4K (Blu-ray)
$17.99
 
Jumanji: The Next Level (Blu-ray)
$15.00
 
Star Wars: Episode III - Revenge of the Sith 4K (Blu-ray)
$28.50
21 hrs ago
InuYasha: Set 1 (Blu-ray)
$27.99
12 hrs ago
Once Upon a Time in Hollywood (Blu-ray)
$15.00
 
Forever Marilyn (Blu-ray)
$31.88
 
Madagascar: The Ultimate Collection (Blu-ray)
$14.99
15 hrs ago
Friends: The Complete Series (Blu-ray)
$69.99
 
Seven Worlds, One Planet 4K (Blu-ray)
$29.99
 
What's your next favorite movie?
Join our movie community to find out


Image from: Life of Pi (2012)

Go Back   Blu-ray Forum > Blu-ray > Blu-ray Technology and Future Technology


Reply
 
Thread Tools Display Modes
Old 08-26-2008, 10:42 AM   #1
Mentasm Mentasm is offline
Banned
 
Aug 2008
1530
3
Default BDs encoded at precisely 24fps - is this wrong?

I've noticed that a few of Optimum's recent and forthcoming BD releases are encoded at precisely 24fps, not 23.976fps like every other BD I own (incliding all of Optimum's older releases). When watching these discs through my BD-P1400 with 24Hz output to my Toshiba 42Z3030D with film stabilization set to standard (120Hz 5/5 pulldown mode) I see regular glitches in the video, almost like a frame skip. I have seen this problem before, when Samsung broke the 24Hz output on the BD-P1400 with an earlier firmware release.

As far as I'm aware, players with 24Hz modes actually send at 23.976, not exactly 24. Is this correct? If so, could the precise 24fps encoding of the video in conjunction with the player trying to send it at 23.976 be what's causing these visual 'hiccups'?
  Reply With Quote
Old 08-26-2008, 02:44 PM   #2
quexos quexos is offline
Banned
 
quexos's Avatar
 
May 2007
Brussels, Belgium
Default

Wow I never heard of a fraction of unit being involved in the FPS. Or do you mean that 24 Frames come in one second and a tiny fraction of the next second ?
Anyways the "Hiccups" are caused by the difference between 24 and 25 FPS in Pal European standards (To the best of my knowledge)
  Reply With Quote
Old 08-26-2008, 02:52 PM   #3
Mentasm Mentasm is offline
Banned
 
Aug 2008
1530
3
Default

No they're not. PAL has nothing to do with Blu-ray at 1920x1080. Even if it did, going from 24fps film to 25fps PAL doesn't cause artefacts. You're thinking of NTSC with pulldown.

The reason the frame rate is 29.976 is for legacy reasons. NTSC is not precisely 30fps/60Hz, it's 29.97fps/59.94Hz. For BDs the original 24fps are slowed down by 0.1% to be output at that speed by any capable player (PS3, most standalone BD players). I've checked virtually all of the BDs I own and the only ones encoded at 24fps are the ones from Optimum. All of the others are 23.976 (well, my software player rounds it up to 23.98, but you get the idea).

I'm just trying to get confirmation from someone with more video knowledge than me whether or not this falls outside of spec for BD? It certainly seems to break 1080p/24 output.
  Reply With Quote
Old 08-26-2008, 03:06 PM   #4
ToEhrIsHuman ToEhrIsHuman is online now
Senior Member
 
ToEhrIsHuman's Avatar
 
Jun 2007
San Diego, CA USA
199
719
2
Default

Actually, the BD spec includes BOTH 24Hz and 23.976Hz field rates so as to which component is causing a problem is anybody's guess.
  Reply With Quote
Old 08-26-2008, 03:13 PM   #5
Mentasm Mentasm is offline
Banned
 
Aug 2008
1530
3
Default

Yeah I know it includes it, but I was under the impression that stuff destined for playback in a home environment was encoded at 23.976 and that all BD players with a 24Hz mode actually output at 23.976. I've never seen a disc from a major studio that isn't. If this is wrong then fair enough, but everything I've read in the past couple of days seems to indicate to this. I've even seen references to certain TV and BD player firmwares being 'broken' for using exactly 24 instead of 23.976. Indeed, an earlier version of the firmware for my BD-P1400 broke the 24Hz output, givign this same jittery appearance (presumably ebcause it was trying to output 23.976fps at exactly 24fps - this appears to be the reverse). It's all a bit confusing.
  Reply With Quote
Old 08-26-2008, 04:07 PM   #6
NutsAboutPS3 NutsAboutPS3 is offline
Expert Member
 
NutsAboutPS3's Avatar
 
Apr 2007
UK
1
Default

How are you identifying how the disc is encoded?

I'm just asking because I've always noticed that some discs have a kind of juddery appearance, while others don't, but the info display on my TV just states 24Hz for all discs.

I doubt that any player converts between 23.976 and 24 because I'd expect this to cause problems if the audio is bitstreamed; the player would need to decode it, speed it up or slow it down, then re-encode it.
  Reply With Quote
Old 08-26-2008, 04:14 PM   #7
Mentasm Mentasm is offline
Banned
 
Aug 2008
1530
3
Default

The software player I use tells me the frame rate. Most BDs show up as 23.98, these new ones are exactly 24. I'm not suggesting anything is altered on the fly though.

Basically what I'm trying to figure out is if video encoded at exactly 24fps would stutter every now and then if output at 23.976fps (as is my understanding of how BD players 24Hz modes actually work).

Or you could look at it the other way, would 23.976fps material stutter at 24fps? It think this is what happened with the Samsung player and also some LG TVs (found some info while Googling).

I'm just trying to get concrete info before I go to the label and tell them. It seems mighty coincidental that I only see these glitches on the 24fps discs.
  Reply With Quote
Old 08-26-2008, 06:24 PM   #8
dialog_gvf dialog_gvf is offline
Moderator
 
dialog_gvf's Avatar
 
Nov 2006
Toronto
320
Default

Quote:
Originally Posted by Mentasm View Post
No they're not. PAL has nothing to do with Blu-ray at 1920x1080. Even if it did, going from 24fps film to 25fps PAL doesn't cause artefacts.
Besides the BIG audio one?

(Or do players apply a pitch correction?)

Gary
  Reply With Quote
Old 08-26-2008, 07:50 PM   #9
Mentasm Mentasm is offline
Banned
 
Aug 2008
1530
3
Default

It's clear that I'm talking about video.
  Reply With Quote
Old 08-26-2008, 11:49 PM   #10
Clark Kent Clark Kent is offline
Blu-ray Prince
 
Clark Kent's Avatar
 
Oct 2007
Metropolis
2
178
Default

BDInfo, the freely available computer program, will give this information for any BD. I think for film based material Optimum is encoding these discs wrong and some BD players are having problems playing some of this material.
  Reply With Quote
Old 08-27-2008, 08:33 AM   #11
Mentasm Mentasm is offline
Banned
 
Aug 2008
1530
3
Default

That's interesting. Have you read any other reports? Obviously I have the problems, but I've not heard of anyone else reporting them. And yeah, BDInfo is very useful.
  Reply With Quote
Reply
Go Back   Blu-ray Forum > Blu-ray > Blu-ray Technology and Future Technology

Similar Threads
thread Forum Thread Starter Replies Last Post
24fps via non-24fps receiver Home Theater General Discussion lt4vette 9 04-28-2009 04:26 AM
Ex Surround Encoded Bd's Blu-ray PCs, Laptops, Drives, Media and Software rlmbluray 5 09-27-2008 03:00 AM
1080p/60hz-24fps vs 1080p/120hz-24fps Blu-ray Technology and Future Technology jd13 11 02-17-2008 05:00 AM
Playback of Divx 5.2 HD encoded DVDs? Blu-ray Players and Recorders 50Hz 3 07-31-2004 11:31 PM
Playback of WMV-9 Pro encoded DVDs? Blu-ray Players and Recorders 50Hz 1 07-23-2004 10:03 AM


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 10:49 PM.