Cameras and Accessories

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You can order software and hardware as one package from CamVFX, our official US Reseller.

Alternatively, you can select and order items you need separately.

Cameras

Sony PlayStation Eye for PS3

Recommended camera for use with iPi Motion Capture is Sony PlayStation Eye for PS3.


Playstation eye small2.jpg

The following properties make it a preferred camera for motion capture:

  • High frame rate — up to 60 frames per second (important for reducing motion blur and capturing fast motions like dancing, boxing or running).
  • Fully automatic configuration with excellent auto-exposure and auto-gain.
  • Good-enough low-light sensitivity.
  • Low-distortion middle-angle fixed optics (75 degrees of diagonal field of view).
  • Efficient protocol for image transfer.
  • Extremely low cost (under $10).

The only major downside of PlayStation Eye is its lack of tripod mounting screw. Possible solutions:

Logitech C922

You can use other web cameras with iPi Motion Capture. But there are just a couple of models that can reliably capture video at 60 frames per second. Logitech C922 is one of such models:

Logitech C922 small.png

It has the following helpful properties:

  • 60 FPS for 720p resolution.
  • Good optics with reasonable field of view (78 degrees in diagonal) and relatively low distortion.
  • Auto-focus can be turned off.
  • Acceptable colors in low light conditions (better than Sony PS Eye has).
  • USB 2.0 interface (USB repeaters can be used).
  • Tripod mounting screw.

Cameras Comparison

Which camera to choose?

Specification Sony PS Eye Logitech C922 Winner Comments
practical frame rate(s) 50 FPS, 60 FPS 60 FPS PS Eye In some cases it is more practical to record at 50 FPS instead of 60 FPS, but C922 doesn't support 50 FPS. Also, PlayStation Eye has more stable frame rate: exactly 60 frames per second, while C922 could drop separate frames time after time and a result actual FPS is slightly smaller than 60.
practical resolution(s) 640x480 1280x720 it depends For iPi Motion Capture it is not so important to have high resolution. Higher resolution just allows to stand farther from camera, which potentially increases maximum capture area. But from the other side, higher resolution means slower processing in iPi Mocap Studio. Thus if your top priority is the biggest capture area, then Logitech C922 wins. In other case - PS Eye wins.
field of view diagonal: 75°
horizontal: 63°
vertical: 49.5°
diagonal: 78°
horizontal: 70°
vertical: 43°
PS Eye PS Eye has slightly bigger vertical field of view. Therefore an actor can stand closer to camera and still be visible in full length.
optic distorsion low low draw Both cameras have good-enough optics for iPi Motion Capture needs.
image quality good-enough
(but poor in low light conditions)
good
(good-enough in low light conditions)
C922 But image quality is not so critical for iPi Motion Capture.
connection USB 2.0
(up to 2-4 cameras per USB-controller)
USB 2.0
(up to 2-4 cameras per USB-controller)
draw Not more than two cameras should be connected to each USB controller to capture at 50 or 60 FPS. But some USB 3.0 controllers can handle up to four cameras at 50 and 60 FPS. This is true for both camera models.
disk usage
(for six cameras)
25 MB/sec
640x480@60
(background subtraction)
35 MB/sec
1280x720@60
(raw JPEG frames obtained from cameras)
PS Eye CPU load is higher as well when recording with Logitech C922.
tripod mounting screw no yes C922
price under 10 USD about 90 USD PS Eye Prices may differ for different regions. But in any case PS Eye is significantly cheaper.

Cables

For distances over 3m, you should use active USB 2.0 extension cables (aka USB repeaters). You can daisy-chain multiple active USB 2.0 extension cables for distances longer than 10m.

Active USB cable.jpg

When combining active and passive cables, make sure that connection order is correct (computer->active cable->passive cable->camera).

Tip.png
Tip: Microsoft Kinect v2 is an USB 3.0 device, thus it would require USB 3.0 extension cables. However, because each Kinect v2 requires a separate computer for operation, there is usually no need in extension cables, because computers can be placed appropriately.

Tripods

Inexpensive 40- or 50-inch tripods like [1] should be fine for use with iPi Desktop Motion Capture. It is recommended to place at least one of the cameras reasonably high (2 or 3 meters high) so you may need a high (72 inch or higher) tripod like [2] or some kind of ad hoc wall mounting solution.

Tripod.jpg

Mini Maglite (or other flashlight) for calibration

You will need a small bright object for calibration. It is recommended to get Mini Maglite for that purpose:

Maglite.jpg

If you cannot get a Mini Maglite, you can use some other similar flashlight:

Noname flashlight.jpg

Alternatively, you can use Sony Move motion controller with white light turned on.

Psmove.jpg

Video Card

iPi Mocap Studio heavily relies on GPU for calculations. Therefore, it is recommended to use a fast GPU for processing recorded videos. The support for DirectX 11 is required (most of the video cards released since 2010 meet this requirement).

Please be aware that desktop GPUs are dramatically faster than laptop GPUs (due to apparent thermal constraints in laptop PCs). Laptops with Switchable Graphics should be configured to run iPi Mocap Studio on a discrete (high-performance) GPU.

You can check expected tracking speed for various GPU model here.

You can Compare and Order recommended GPU from Amazon.

Note.png
Note: Professional GPUs like NVIDIA Quadro or AMD FirePro are not recommended due to high price and lack of performance advantage. You should understand that Quadro/FirePro video cards are designed for very specific professional OpenGL-based workloads. Their main advantage is high image quality in OpenGL rendering. iPi Motion Capture needs raw 32-bit floating point performance and does not benefit from image quality features of Quadro/FirePro video cards. For best performance, use top gaming-class video cards from NVIDIA GeForce GTX or AMD Radeon R9 series.
Tip.png
Tip: Ensure that you are getting maximum of GPU's performance in iPi Mocap Studio.

USB controllers

All modern computers (e.g. dual-core and better) based on Intel, AMD and Nvidia chipsets have at least two USB 2.0 controllers on board. With two USB 2.0 controllers you've got enough bandwidth to record with:

  1. 2 depth sensors (first generation Microsoft Kinect)
  2. or 4 cameras at 640x480 at 60 FPS
  3. or 6 cameras at 640x480 at 40 FPS

Some modern laptops have both USB 2.0 and 3.0 controllers. In this case single USB 3.0 controller can handle with four PS Eye cameras at 640x480 at 60 FPS.

Important.png
Important! Kinect 2 for Windows, Kinect for Xbox One requires USB 3.0 controller. Kinect SDK 2.0 currently supports only single sensor on one PC.

You can check how many USB 2.0 / 3.0 controllers you have in the “Universal Serial Bus controllers” section in Device Manager. Operating system will display USB 2.0 controllers as USB Enhanced Host Controller (not to be mistaken with USB 1.0 USB Universal Host controller). USB 3.0 controller usually works in USB 2.0 mode, so it will be represented by 2 items - USB 3.0 Host Controller and USB Enhanced Host Controller

USB controllers.png

Alternatively, you can use USBView utility from Microsoft which allows to view all USB controllers and devices in a more convenient way: Download USBView

You should make sure that you have depth sensors or cameras evenly distributed between available USB 2.0 (or 3.0) controllers. For example, if you have four PS Eye cameras, you should connect two cameras to first controller and two cameras to second controller. (But some USB 3.0 controllers can work with four cameras.) Device Manager usually shows USB cameras as “USB Composite Device” at the “Advanced” tab of USB controller properties. If you have too many cameras connected to single USB 2.0 / 3.0 controller, you should re-plug them to different USB ports.

USB hubs

If several devices are connected on the USB hub and working in parallel, then the USB bandwidth is shared among the devices. Connecting all cameras via single USB 2.0 hub is OK only for low resolution video recording (320x240). To be able to record video at 640x480 and 60 frames per second, you should avoid connecting more than 2 cameras via single USB 2.0 controller and more than 4 cameras via some models of USB 3.0 controllers.

Solution if your PC lack USB controllers

If you do not have enough USB controllers, you can either add USB controller to your PC, or use several PCs and Distributed Recording feature.

  • For desktops you can use PCI USB controllers.
  • For laptops there are USB controllers for ExpressCard and eSATA slots.
Important.png
Important! Please refer to Potential issues with USB controllers and Known compatibility issues sections below before buying a controller.

Potential issues with USB controllers

Some USB chips have compatibility issues with specific cameras which may result in not detecting cameras, low frame rate, etc. See the next section on known issues.

Many modern laptops have one of the integrated USB 2.0 controllers reserved for docking station. That may effectively halve your USB bandwidth. So laptops with a large number of USB ports (4 or more) are preferrable. Desktop PCs should not have such problem.

Important.png
Important! Before buying a specific laptop model it is strongly recommended to ensure it has the sufficient number of available built-in USB controllers and they are compatibile with cameras you intend to use. Find it at your local retailer, and bring cameras with you to test. Though it may be easier if your friend/neighbour has such a laptop. Or ask at our forum, maybe someone already used this model with our software or can recommend specific model for your camera configuration.

If you plan getting an additional USB controller, please be aware of potential problems with USB 2.0 controllers available on the market. Many USB 2.0 controllers are based on defective NEC USB 2.0 chip, not capable of standard USB 2.0 speeds. That's a well-known bug specific only to NEC USB 2.0 chip. By contrast, all NEC USB 3.0 chips are good and do not have this problem.

Some manufacturers sell what they call a "USB 2.0 ExpressCard" controller for laptops. Many of such ExpressCard controllers are in fact internal USB hubs in ExpressCard form factor. That means they do not add actual USB bandwidth to the system. All USB 3.0 ExpressCard are controllers.

If you plan getting additional high-speed USB controller, we strongly recommend that you get a USB 3.0 controller, just to be on the safe side.

When setting up a USB 3.0 controller, make sure you configure it to handle USB 2.0 traffic (as opposed to passing USB 2.0 to integrated USB 2.0 controllers in your chipset). There should be a corresponding setting in driver properties or in BIOS.

Known compatibility issues

Combinations of camera & USB chip listed below have known compatibility issues. Unfortunately, there is no guarantee that other combinations will work for sure, but most will. If you need an additional USB controller for connecting specific camera, be sure not to get the one based on incompatible USB chip.

Camera USB chip Symptoms Comments / possible solution
ASUS Xtion (Live) NEC µPD720200 (USB 3.0) Camera is not properly recognized by the system. This firmware update makes device behave the same as PrimeSense Carmine 1.08 with this controller.
ASUS Xtion (Live) VIA VT6212L (USB 2.0) Frame drops of color picture in 640x480@30 (depth + color).
Microsoft Kinect v1 Intel 8x/9x chipset series (built-in, USB 3.0/2.0) Multiple Kinects do not work. Discussion of the issue
Additional USB controllers needed for multiple Kinects.
One user reports that uninstalling Intel USB 3.0 driver resolves the issue.
PrimeSense Carmine 1.08 NEC µPD720200 (USB 3.0) Frame drops in 640x480@30 (depth + color). Stable work in 640x480@30 (depth only) and 320x240 (depth + color).
PrimeSense Carmine 1.08 VIA VT6212L (USB 2.0) Frame drops in 640x480@30 (depth + color). Stable work in 640x480@30 (depth only) and 320x240 (depth + color).
PrimeSense Carmine 1.08 VIA VL800(USB 3.0) Frame drops, reduced frame rate, freezes in depth + color modes. Stable work in depth only modes.
Sony Playstation Eye VIA VL800 (USB 3.0) Great number of bad frames and frame drops. Camera is invisible to iPi Recorder.
Sony Playstation Eye VIA VT6212L (USB 2.0) Great number of frame drop in 640x480@60 mode. 2 cameras can work smoothly at lower FPS (up to 640x480@50).
Sony PlayStation Eye NEC µPD720101 (USB 2.0) Great number of frame drops. Camera stops producing frames. Not recommended to use. Replace with other controllers.