In terms of quality, occlosion, capture area, setup/calibration etc.


Thanks
Eran

Hi Eran,


The Dual Kinect iPiBasic Mocap System is much better in my opinion.

The calibration is faster and easier than the PS cam setup.

There is hardly any occlusion in the 180 degree calibration.

The quality or rendered and produced animations is fantastic and second to none IMHO!!

There is a trade off that the capture area may be a little smaller but the results are well worth it...

http://www.youtube.com/playlist?list=PLE7D44FEC9D5AF230

Is a well documented series of videos explaining the whole process.

I have both systems and I do use both. Which system I use depends on what I need to capture and how quickly I need it.

Here's a summary of each system and their advantages and disadvantages:

Single Kinect is ridiculously easy to setup. Quality is good but capture range is limited (meaning types of motions and the size of thespace you can record in.)

Dual Kinects a more complicated but still easier to set up than PS3 Eye. Quality is very good but capture space is actually smaller than with a single Kinect. However, it's large enough for many types of activity so long as you're not walking or running around much.

Six PS3 Eye cameras will create a higher volume resolution, which results in the highest quality capture from iPi DMC. The PS3 Eye configuration also has a significantly larger capture space than Kinect--large enough to run around in a parking lot and do all sorts crazy acrobatics. The downside is that setting up a PS3 Eye session requires a bit more planning and effort, and it definitely requires a more powerful computer.

According to iPi, dual Kinect quality is comparable to what you get with four PS3 Eye cameras. I think this is referring to the 'cleaness' of the captured volume. Theoretically, six cameras will give you a 'cleaner' more accurate volume to track becase even though Kinect has depth, it still only captures from two viewpoints of the scene.

Framerate is probably the most important factor in getting accurate captures. Framerate for PS3 Eye is 60 fps, twice that of Kinect which is only 30 fps. This makes PS3 preferable for fast or subtle motions. That said, Dual Kinect is very capable of capturing many fast motions.

Cost for each system is probably about the same once you figure in all the accessories and equipment requirements. (Browse back through the forums for details...this topic has been discussed many time in the past.) At a glance, the cost with PS3 Eye may seem cheaper ($35 each) but you may also need a more powerful computer plus accessories, which could offset the cost of two Kinects (about $300 for a pair.)

IMO, most people will want a Kinect setup because it's convenient and requires less computer power. It's a good value for a very capable system and you'll see useable results faster.

Anybody who needs to capture 'really big' motions or needs higher quality will want to upgrade to the six camera PS3 Eye setup but they should probably start with Kinect setup before going down that path. The PS3 Eye setup can get very involved and it not only allows a larger capture space, it requires one.

So, back to the original question: 2K or 4PEs? If these are the choices, go with the Kinect. As mentioned above, quality is comparable and Kinect is a lot easier to use. But if you need a bigger capture space, go with 4 PS3 Eyesm and understand that you will also need a more powerful computer and do a lot more planning for your sessions.

For the moment, I really like the Dual Kinect configuration, and will probably only use the PS3 Eye setup for 'special' actions when I need them.

Hope this info is helpful.

G.

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!

I would vote for Dual Kinects as well. Here's why:

30 days wasn't nearly enough to comprehend how the calibration really works for PS3 cameras. Sometimes it did, most of the times not. Typically I had to set one of the four camera coordinates and tilt angles manually. This was hard work but necessary. If one of the camera coordinates was way off after calibration, it was hopeless to even try correction manually.

We have 50Hz frequency for electricity here in Finland. Recording 60 fps seems in the resulting video like the lights would be flickering tremendously. It is unknown to us, however, how this affects the tracking. This wouldn't be a problem for Kinect, I think.

Lights... You don't need light for Kinect, at least not so much. During the winter when it is dark outside (here) whether it is night or day, one would need some powerful lamps. Which would create shadows, which couldn't be positioned so, that they are visible to cameras etc. With Kinect - no such hassle.

Clothes. I guess you don't need them with Kinect... With PS3 cameras, they are a necessity. Sometimes the system was very picky about them, too. Pink shirt was way worse than a red one, for example. Knee pads weren't a good idea either, they got mixed with feet due to their dark colour. If you need to be holding something in order to make the acting more natural, it sometimes gets mixed with your hands etc.

We had one faulty USB extension cable. This was not easy to track down since the camera always worked very well for a few minutes and then the picture froze. At first we thought it was due to the laptop which was just able to record from 4 cameras anyway. Then we blamed the camera, which was bought secondhand. Which gets me to the point: you need a lot of extension cables with PS3 cameras. And nowadays, even new cables can easily be faulty. Kinects, on the other hand have quite long cables as default. They work with extension cables, too, if you need them.

It is not my intention to critisize iPiStudio, just to point out the drawbacks I've found in trying out the software. Just in comparison, Kinect has some major flaws as well:
- one Kinect is almost useless, you absolutely need two of them
- 30 fps might not be enough
- without RGB video available, it was not easy to see always (with your own eyes) where the actor is in the picture (this is fixed now in current version, but not working for everyone according to some posts in the forum)
- cannot be used outside, or at least extremely difficult to do so
- require their own power source (but since you cannot use them outside anyway, this is not really an issue)
- very limited tracking space in every direction

This is just my experience but calibration with PS3 Eye has always worked flawlessly for me. But as you pointed out, good connections are key to making this work. Lighting is irrelevant for calibration other than the Maglite.


Somebody else mentioned this issue in the past. I imagine it's annoying to look at but FWIW iPi says the flickering will not affect tracking.


This is very true, and it's one of the key reasons I prefer Kinect right now. When I use my PS3 Eye system I have to carry my computer to another location where I have set up a stage with proper lighting. That said, many users have successfully used the system in a normally well lit environment (a large hall or outdoors.)


Yes, clothing is very important for PS3 Eye, though I don't think the system isn't quite that picky. For me, basic blue jeans (not too loose,) a black T-shirt over a red long-sleeved shirt works perfectly fine. Clothes were purchased inexpensively at a local Old Navy store. BTW, iPi has also recommended blue jeans, and red or green shirt with a black T pulled over.

As for Kinect clothing requirements, there are a few. Clothes should be 'normal' fitting, i.e., not too baggy or otherwise affecting the shape of a human being very much. Large pants, wide shorts, extra long T-shirts, will obviously confuse the tracker.


Were these active extension cables or just standard USB cables. You absolutely need active extension cables (aka Repeater cables,) to extend USB for longer than 10 ft, otherwise the signal will get too weak to function reliably. Active extension cables have a box on the end, usually with an LED to show they are working. You can buy these for about $12 at many online electronic stores. (I get mine from Newegg here in the States.)

To clarify, Active USB Extension (Repeater) cables are needed to reliably extend either PS3 Eye cameras or Kinect Sensors.


I disagree. I originally shot Happy Box entirely with a single Kinect and the results were quite good. I did wind up re-shooting with dual Kinect because of the quality difference, but I was not unhappy with the original captures. In fact I kept a couple of the single Kinect motions in the final version of 'Happy Box' because it was unnecessary to replace them.


RGB is not necessary for the system to work properly. In fact, I had it disabled completely for Happy Box to speed up the process. That said, I will be using it on our next film because I will need to reference some very subtle movements that the tracker may miss.

Anyway, that's just my personal opinion and experience. Mileage may vary of course.

G.

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!