Let's set this straight - No one can do 24p consistently well - Page 38

I thought I read in another thread that setting a custom resolution in nvidia took it to full 0-255 without the need for a hack?

Yes, if you create a custom refresh rate "23Hz", B&W levels at "23Hz" will be Full-range RGB, but you can't go back to Limited-range RGB any longer (though not important). Moreover B&W levels at other refresh rates are still Limited-range RGB. Only the registry hack gives you the complete solution.

Okay. My BD mkv's look fine (23.976) and my Live/Recorded TV look fine too (59.94) so I'll just leave it alone.

Which will give me closer to 23,976; AMD or NVIDIA? I read somewhere that a custom NVIDIA 23,978 profile results in 0-3 dropped frames for a 2 hour movie. Sounds pretty neat to me.

Out of the box, the Radeon cards will do a better job of getting close to 23.976. The 6450 in particular is very accurate, with no adjustments (other than setting XBMC to match source framerate and setting up the 1080p/23 supported resolution in the AMD tools) it can run for something like 5+ hours with no dropped frames.

Anandtech did a test in which they published the frame-rate that they could achieve with a large variety of video cards. I imagine that they also provided information on which drivers they were using.

In this test, the 6450 was the most accurate and if I recall required the least hoops to get solid 23.976 playback out of.

http://www.anandtech.com/show/4380/discrete-htpc-gpus-shootout

Lots of good info in that one.

//update. It turns out that they were able to get a solid 23.976 out of their GT430, but only after tweaking with custom resolutions. "Out of the box" the 6450 provided 23.977 which I believe results in zero frame drops in a 3 hour long movie.

Fair enough. The bottom line is that until PC hardware manufacturers take the HTPC enthusiast crowd seriously, those of us who notice frame drops will continue to deal with these issues.

For me, personally, I do not want to have to mess around with custom resolutions and clocks.... especially when different drivers, different card versions, etc, all result in different approaches to getting accurate 23.976 output.

I've upgraded the drivers on my 6450 several times and none of the driver updates have had any impact on the 23.976 playback accuracy that I have noticed.

In other news, Onkyo finally (and very quietly) acknowledged the 23.976->24.000 output bug on their 818 AVR and issued beta FW that fixes the problem.

The only time I see frame drop is when the video starts and if I hit CNTRL J... Otherwise, smooth as silk.

There are quite a few of us who notice them without obsessing over counters and other things.

Initially people did not think that the Onkyo was messing with the 23.976 output because "they did not see a problem", but I could see the annoying jerky behavior of frame dropping. Sure enough, they were buggering the 23.976 output and sending it as 24.000 which resulted in a drop ever 30 seconds or so. This was confirmed by people with video processors and eventually fixed by the vendor.

Some of us are just more sensitive to this than others, and my own personal suspicion is that the bigger the TV the more obvious it is.

Intel HD video does not drop a frame every 30 seconds as it gets pretty close to 23.976. I like and use my $60 GT 430 with madVR for things other than framecorrecting frame drops drops.

Dam phone. Sort of had some word repeats there..

Dam phone. Sort of had some word repeats there..

Well, how close does it actually get? How many frame drops in a typical 2-3 hour movie? Because once the movie has started anything more than zero is too many.

Maybe I'm just lucky, or maybe I just don't understand how all this works (more likely! ) but in xbmc if I click O while playing a movie, the diagnostic screen shows I get 1 or 2 drops right at the start of the movie, and then no more after that, at least for a while, I haven't checked after a whole movie. I have an i3 and am using the onboard gpu. So did something change since this thread started? I got the impression from this thread that I would be seeing drops every 42 seconds.

Intel: ~30 dropped frames in a 2 hour movie:

1 / (23.976 - 23.972) s/f (second per frame) = 1 / (0.004) s/f = 250 s/f = ~4 m/f,
(2 h) / (4 m/f) = 30 frames
Edited by renethx - 2/28/13 at 5:51am

It's the days of G45 and the 1st gen Core processor family (Clarkdale) when 23Hz = 24Hz = 24.000Hz so that

1 / (24.000 - 23.976) s/f = 41.7 s/f.

With SNB and IVB, it's prolonged to 4 min per frame.
Edited by renethx - 2/28/13 at 5:52am

Then you just didn't see some of the dropped frames. And no reason to care about what you don't see.

Because of XBMC...

Is XBMC reporting it wrong or does it do 23.976 better than MPC-HC?

There are two types of dropped frames:

1. Dropped frames due to the player's internal glitches (e.g. hardware is not fast enough to execute post-processing algorithms)
2. Dropped frames due to a difference between the media framerate and the desktop refresh rate.

XBMC reports only the first type of dropped frames, while we are talking about the second type of dropped frames in this thread. OSD of XBMC tells nothing about the latter.

So I guess cntl+j in mpc-hc reports both types of drops? Are there other tools to see this with? Not too interested in setting up mpc-hc... yet...

It's really just out of curiosity, if I see more drops I promise I won't panic

My contention is that if you cannot see the drops while watching the film why do you want to go looking for them with a tool?

I agree. For someone who has a history of noticing the issue though, the counters can be a useful way of validating their setup.... verifying that they don't have frequent frame drops before firing up a favorite movie with a brand new setup for example.

That is one frame out of every 6000 frames. Not very many on the grand scheme of things but with madVR and nVidia with very little time spent tweaking the custom resolution (one iteration) it is more like one frame drop per hour or 2 for an entire 2-hour movie.