Timelapses can be amazing, beautiful, strange, provocative. And FUN!

The day I discovered the GH2 could do 2fps I got so excited, I loaded up a full battery, put the camera on the balcony and aimed it at the shopping mall door. I got over 3+1/2h of Cinema 24p footage (@2fps) and after speeding it up 15x (to 300fps) in VirtualDub I almost couldn't believe my luck. This is what I got and I have yet to grade it properly:

Since that event, I wondered about the best way to patch up the camera to capture them. MJPEG was the obvious candidate. It's a Full Intra codec and it can be setup to capture just 2fps. That means absolutely no wasted frames unlike AVCHD, so MJPEG must be great, but there was a caveat: even with stock settings there was a capture time limit that was well below AVCHD. How is that possible since it's only capturing 2fps, the bitrates have got to be frugal? Well, it happens that there is a 2GB filesize limit within MJPEG so even after taking Driftwoods Quantum 100-50's MJPEG settings and cutting the quality to take half the bitrate, you will end with less than one hour of footage. Compare that to AVCHD and you see what got me started.

Then there was the IQ issue. I stumped into this: http://sonnati.wordpress.com/2010/10/19/h-264-for-image-compression/ which made me start another full set of tests (http://www.personal-view.com/talks/discussion/2111/gh2-mjpeg-resolution-findings-and-myth-busting/p1) in which I found that unlike most crazy MJPEG resolutions that only seem to be 720p upscaled, the one used on Driftwoods patch was the best that ATM can be extracted from MJPEG and that even rivals with AVCHD. That test ended up on a tie, so in my book AVCHD wins for flexibility and recording time.

At the same time these tests were taking place, I fought a lot with the stock settings trying to make a patch that used GOP 13 and yes, that's the frequency at which you see major block changes when you set the shutter speed to 1/2s. This GOP13 would insure excellent quality as it makes the result Full Intra once you trash the needed frames. But the frames and limits and buffers and modes were giving me all kinds of speed messages Hell. By that time I also discovered that the null B frames that encoded no changes at 2fps were much larger than P-Frames which also appeared a lot more frequently than I wished they would. Null B-Frames were 2.5x bigger than P and when there was movement, the P-Frames would take as much space (and sometimes even more) than I frames, so I had to do something about it to make it more efficient. Meanwhile Nick @Driftwood and @LPowell were kind enough to share their knowledge and let me in on a few tricks. These allowed me to suppress B-Frames altogether and starve P-Frames to death.

So here I was armed with a bazooka and a missile and I couldn't even fire a pistol. Then a few days ago @Balazer came out with his Cake patch featuring a completely VBR approach through a Constant Quantizer as if he couldn't care less about bitrates, limits or buffers or all the stuff that was putting me down. I tried it a 2fps and I couldn't believe how well it worked. And since the frame rate I'm using is ridiculous when compared to normal video modes, there are no speed/buffer/spanning issues even if you have the slowest SD card in the business. In this case, this VBR aproach is a no brainer and the cherry on top is that you get Constant Quality at Quantizer 22 which is very very good IQ!

So, hands to work, bake the Cake, mix Driftwood's MPEG settings, apply the P/B-Frame tricks and it was working on the third try. :O

It could have been a lot faster as I tried to best the 60i mode and leave all other modes alone. It ended up being the wrong choice because the 60i GOP isn't sticking and probably the Interlacing is making too big P-Frames around the I-Frames. In the end I managed to use tweak 24p for timelapses and the frame usage when there is no movement is a beautiful set of I-Frame spikes with all else almost null. 60i is now GOP13 on I/P frames exclusively and the P sizes look generous, so the starved P-Frames on 24p don't seem to affect it. 720p modes seem also unaffected. In the end this patch tries to give you the best 2fps and still leave you with 2 very workable modes without repatching: 1080i60 and 720p.

USE IT AND ABUSE IT. DON'T forget to weed out the starved frames in post. AfterEffects instructions here: http://www.personal-view.com/talks/discussion/comment/49325#Comment_49325 and freeware workflow is here: http://www.personal-view.com/talks/discussion/comment/39079#Comment_39079

Thank you @balazer for baking Cake.

Thank you @drifwood for the MJPEG settings and no B-Frame trick.

Thank you @lpowell for telling me how to starve the P-Frames.

Thank you @cbrandin for StreamParser 2.4 which gave me wonderful new numbers.

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VERSION HISTORY :

1 - TimeBuster 1 - First Release

• Based on Cake v1. It uses GOP13, a Constant Quantizer VBR approach without B-Frames, minimum P-Frame size and quality.

2 - TimeBuster 1.1 - with 2 significant changes:

• Now based on @balazer 's Cake 1.1, it has switched to use the Rate Control mechanism from @LPowell 's FlowMotion 100.

• 720p mode was broken due to use of a very low quantizer (12) which lead to skipped frames in 720p. It now uses QP=20 on both 720 & 1080 modes which will have an observable effect in both bitrate & quality even though it still gives you 24+ hours on 64GB.

3 - TimeBuster 1.2 - with 1 significant change for a fully featured 720p mode:

• Since @balazer 's Cake 1.1 is now heavily based on @LPowell 's FlowMotion 100, I decided to copy LPowells 720p settings since they will probably play better with the other modes. The only difference on 720p is a constant QP which had to be lowered yet from 20 to 21 because it still dropped frames on torture charts and/or sometimes present speed issues at very high ISO (>3200) on Class 10 SDs.

4 - TimeBuster 1.3 - with a lot of significant changes:

• Ported to PTTools 3.64d

• Savings on P-Frames is now accomplished by using a Scaling Table that is full of 0xFFFF for 1080p modes.

• Quantizer boundaries were removed since they are now much more dependent on the new Quantizer Tables.

• Redesigned for merging, these definitions try to be as independent as possible from their re-packaging definitions (in this case FlowMotion 1.1) and are published in two flavors: Timebuster 1.3 Base (for merging) and Timebuster 1.3 FloMo (merged with FlowMotion 1.1)

NOTE1: Timebuster Base 1.3 was merge tested with @LPowell 's FlowMotion 1.1, @Balazer 's Cake 1.2 and Nick @Driftwood 's Quantum X (v2) with minimal impact on all modes except for 1080p. I recommend FlowMotion or Cake for the simple reason that the 1080p24 Frame Limit is set to a much higher value in these settings. In fact, if you care for nothing other than the 24p timelapse IQ and don't mind impacting some of the other modes, you should set it to 10,000,000.

NOTE2: Merging Timebuster Base 1.3 with other settings is easiest done by loading Timebuster Base 1.3 first and then Alt+Clicking your choice of merger.

5 - Timebuster is now comprised of 2 main variants:

a) 24h Timebuster 2.0 - with the following changes (from TimeBuster 1.3):

• The GOP for 24p is now married to 2.5fps. The bitrate hit is a little above 20% but the recording length can be easily compensated by raising the QP. As a benefit it's still very close to 2fps and it's the closest to a 360º shutter we can get on 24p.

b) 24h TimeHBusteR 2.0 (NEW, uses HBR 30)

• Similar philosophy to 24h Timebuster 2.0 Base but as the name suggests, uses HBR mode instead of 24p. There is another difference, P-Frame quality is fully preserved as this kind of frames is used for one of the interlaced slices on Key Frames.

• GOP married to 1/2.5 on HBR 30p (NTSC) and to 1/5s on HBR 25p (PAL). The big benefit is that both are using a 360º shutter. Uncheck "1080i50 and 1080p24 GOP Size=5" before merging if you don't plan to use Shutter Speed (SS) =1/5s and want to better preserve the 24p mode and HBR 25.

Both variants are now:

• Using B-Frames. There is a 6% penalty in bitrate usage but this was necessary to make sure the QP was respected. I believe the gain from setting the QP at will is just too great to ignore, since not everyone wants to record for 24h straight. QPs as low as QP=16 were tested and theoretically it could go as low as QP=12 @ISO160 when merged with FlowMotion 1.11 on regular tripod mounted footage.

• GOP married to 2.5fps. The bitrate hit is a little above 20% but the recording length can be easily compensated by raising the QP. The reason behind this was getting as close as possible to 360º.

• User definable GOP - GOP can be set at will according to intended SS, use the attached "GOP-SS-table.png" to look up the right value. Defaults settings are SS=2.5fps and GOP 1080i=10 for 24h Timebuster 2.0 and SS=2.5/5fps and GOP 1080i50/i60=12/5 for 24h TimeHBusteR 2.0.

• User definable QP - QP can be set at will according to desired IQ/recording length. I've gathered quite an amount of information so that in the future I can make an Excel tool to estimate the best QP from Card Size/Footage Snapshot/Desired ISO/Recording Length. Default settings are Q24/23 for 24h Timebuster/TimeHBusteR.

As before, there is the Base Release to be merged at wish with popular settings (load Base first in PTTools and then "ALT+Click" your choice of merger) and there is also the FlowMotion Release (already merged with FlowMotion 1.11). I've merge tested against @lpowell 's FlowMotion 1.11, @balazer 's Cake 95, and @bkmcwd 's GOP3ZILLA and no undesirable effects were observed. The key is using a VBR settings definition with a very high "1080p24 Frame Limit", especially if you are going for a low QP (<22).

(edit) If you want to merge with Nick @driftwood 's settings, I recommend going for Cluster v1 as shines in being both a long GOP set and also having the biggest "1080p24 Frame Limit" of all the sets I know.

6 - Updated Release of Timebuster/timeHBusteR 2.02 FlowMotion - WARNING HBR version IS BROKEN at 24p

• (EDIT) This turned out to be a rushed release. Several users have reported problems with timeHBusteR (the HBR variant) It looks like FlowMotion 2.0(+) is highly dependent on GOP length (trough heavy use of GOP Tables, GOP Opt Tables and GOPx2 parameters). I'm investigating other possibilities right now so watch this space for further news. In the meantime I recommend you stick to timeHBusteR /Timebuster v2.0.

Since FlowMotion 2.02 looks very stable now, I'm releasing my pre-merged versions of Timebuster/timeHBusteR. There is nothing new regarding timelapsing except for FlowMotion's 2.02 changes.

• 24h Timebuster 2.02 FlowMotion which is 24h Timebuster 2.0 Base merged with FlowMotion 2.02

• 24h timeHBusteR 2.02 FlowMotion which is 24h timeHBusteR 2.0 Base merged with FlowMotion 2.02

7 - Updated Release of Timebuster/timeHBusteR 2.02 FlowMotion variants - 24p is now fixed on timeHBusteR. There was a note telling you should remove the "1080i50 and 1080p24 GOP Size=5" for better preserving 24p but no one seemed to read it and it was causing more trouble (to most of those who wanted 24p preserved) than it was worth (for those who wanted more timelapsing versatility.

NOTE: The mergeable timeHBusteR wasn't updated! Just the the FlowMotion variant. I ASSUME that if you are using this base for merging that YOU KNOW WHAT YOU ARE DOING, and read the DOC.

The day is not over. :)