@stonebat

They have their uses still... I just like running around like a madman with the glidecam... it's so light!

Shoulder rigs w/monitors for dialog-blocked scenes... and glidecam rig for everything else. That's my ideal setup! :)

@bkmcwd Many thanks for testing, yep there are still some problems to do with the FB sizes I think. Will work on it some more today. Going to stop trying with the FSH/SH settings ands focus only on 24H and L. Well I will, once the in-laws have visited that is. I've not seen a cadence problem as bad as you are though, just a drop in the odd random GOP with no obvious pattern like your tests.

@eiji They work fine - let the encoder work it out off the given bitrate, AQ & vid buff, you can always tune them, not sure about your own 720 settings though. Doing 720 tests this wknd.
Nice low GOP results it seems. :-)

@rojo
Are there any span issue with this settings?

Okay, I'm giving up on the 66Mbps GOP 6. While it may be possible to create single settings for a low GOP with 100Mbps+ bitrates (although I haven't seen any settings posted in this thread that I've personally found stable). I think, for example, that while you could tune say 24H to run at a GOP lower than 12 you're not going to get a lower bit rate performing in a stable fashion out of 24L.

I'm only guessing here, based on what Vitaliy and Chris have said and looking at everyone elses results and thoughts, and the stable 44+66 settings Chris has posted. Vitaliy said some days ago to leave the video buffer size alone, as it's okay. Chris's settings that he has posted do this, but change the FB + FL. I'm guessing from this that the video buffer is only storing encoded frames before they go out to the card, and the FB+FL are governing the space where the actual encoding takes place. Yep, a wild extrapolation, so if I'm wrong please correct me. Also, that we know that the codec in its current form is geared to working in GOP 12 only. From these assumptions, rightly or wrongly I took this approach... I took a static shot with the stable GOP12 66M version, and then one with my work-in-progress GOP 6. I looked at the size of a GOP for both in streamparser, and worked out the bitrate ratio between them saying that 2 GOPs at 6 = 1 GOP at 12. The GOP 6 version was using 20% more bandwidth than the GOP 12 version. As the stable GOP12 had an FB + FL set to *3 I set them to *3.6 to cover this increase. The thinking behind this I'd be the first to admit is a bit woolly, in that my line of thought was 'well its waiting for 12 frames to do its encoding, irrespective of the GOP, or the I-Frame count in that set.' Well, the result was a 24H that seemed really stable, until I ran it through the deathchart and got a nasty pumping cadence.

The cadence pattern however does become a pattern, eventually, so this makes me feel that it is a buffer issue and maybe you could tweak it so it isn't falling over or under the buffer size during encoding a whole GOP (or 2 if its GOP 6, or 4 if its GOP 3 etc). Its not in a predictable pattern until a way through the stream, the low usage at the start of every stream I think creates this effect (I am talking here of static shots with low noise). If you could do then all bets would be off for 24L as the sizes, bitrate, buffer use is going to be wholly different. Am I right in any of this ?

@eiji No I haven't, I may do, if only to see if I can learn something from testing them.

However, these settings are unusable to me, that bitrate is way too high, and too high for a lot of other ppl I think. As has been proved in the maximum image quality thread the codec as it currently stands hits max IQ at a much lower bitrate than that, so to me there is little point taking such a masive hit on file size just for a GOP 3 motion. As it is for me a GOP 6 motion, as per the earlier version of Ptools is the look I'm after, I really didn't like the look of GOP 3. The settings I have for 66M GOP6 have exactly the look I want, and while they aren't stable they are pretty close to it, particularly with low noise and consistent lighting. Hmm.. I will probably try that 132M because I suspect that while it seems quite stable I'm going to see that it will probably exhibit the same problems my GOP 6 is. I don't think myself that throwing higher and higher bitrates at this, the way the codec works at the moment, is going to be the solution. I could be very wrong, but I'm going to stop testing for a while and go back to shooting with the GOP12 66M AQ2 until new information arrives, or a new release of Ptool. At the moment I've exhausted all the possible routes I can think of to create a GOP 6. I don't want to do the T4=T1 thing again, I don't like its associated drop in frame size. Yeah, I want the moon on a stick, I know ;).

Edit : Also, Have you tried to get a stable 24L with that ? Another thought, running at that kind of bitrate it would make sense to me to have AQ always at zero or 1.

@eiji I tried 720p60 GOP6. I couldn't test it thoroughly. But I tested high shutter speed at 125 and 250. Well it's not really high shutter speed as that's what I normally use for getting very slow motion video.

It kept failing. 9 out of 10 times. It freezes after first second.

@stonebat
strange... didn't try shutter speed at 250 but I shot a whole day at 720p60 GOP6 shutter speed 125 and except 3 lockups everything went fine. The graphs I've attached above come from that footage.
At what value did you set the AQ? and what was your test subject?

Well... it may just be because of the AF.
The tests I've done were all shot with the Voigtländer 25mm so everything MF.
Maybe just try to lower the AQ to 1 or 0. Anyway for a shot with a lot of movements and details it's not so useful to set the AQ high, right?

@stray +1. I'm hoping for 1080p24 66Mbps GOP6 AQ3 when the next PTool gets released.

720p60p 64Mbps GOP6 would be very nice matching to it. When it's conformed to 24p, it would have 4 I-frames per second which is GOP6 in 24p.

GOP 1 Final Results for short GOP freaks

Finishing off last night's GOP 1 tests (which included a helluva lot of filming), this is what I've discovered.
It's impossible to get stable GOP1 using AQ - even taking the bitrate to ridiculous levels such as 220M.
However, I have evaluated numerous IQ and Q 1080 settings (over 50 firmware upgrades! ) and can announce to all GOP 1 freaks that the most stable setting to the limit (ie highly detailed to movements and back) you're going to get is the following;-

154M IQ = 20, Q=26 (best stable quality)
Edit: Needs adjusting still. Won't import into a few NLEs

You will get eventual failure on any other settings with highly detailed scenes - ie mainly movement going to a static and vice versa.

i/ 132M at the above rates on high detail movement to a static will fail around 30+ seconds
ii/ 140M just about gets away with it, but I wanted to be safe and stuck to an even/lowest working multiplier - hence why I stuck with 154M (x7 the default). anything above 154M will work but no further benefit in i frame size.
iii/ AQ=0 will NOT, repeat, NOT, reliably work even at 176M (dieing at 4 seconds) under strong detail movement.
iv/ Q=26 was the lowest stable quant metric I could get. (don't groan - its not that bad for movement!)
v/ I tried lowering the IQ to lower than 20 to no avail & with IQ=20 and lowering Q.
vi/ I tried lowering the IQ to lower than 20 with Q= >26 to no avail on many tests.
vii/ The max buffer fullness will reach around 80% on high detail movement to static. See buffer chart.
viii/ My result setting has constant good writes to decent type10 cards.
ix/ No playback in camera with this extreme setting. Would you expect it?!!!

Tested with 50mm 1.2 stopped down to 4, less than or = 800 iso, various normal to high shutter.
My Film mode: 0, -2,-2,-2

Here's the setting, hope it works for you like it has for me but you need a top end card to use this. Of course, things could be fine tuned, this is a stable basis to start from but defo gonna need a tuneup...

Brilliant when some of the files import ok. If you love the effect of short GOP. Mainly plays back ok in VLC and OSX Movist, when it works it looks terrific. Mac MplayerX & Windows Media Player = jumpy.

Edit: Some files seem to import/ cut in FCPX ok. Premiere Pro seems to hate it (jumpy)....

cant see any cadence at 132 - the hi bitrate puts it in the comfort zone it seems.