How many digital video cameras can I use with a desktop system to capture live synchronized videos?
You can use a maximum of 6 digital cameras to capture synchronized video using PCI cards.

How many digital video cameras can I use with a notebook to capture live synchronized videos?
3 digital video cameras can be use if the notebook has a built-in FireWire port (a.k.a. iLink or IEEE-1394) and 2 PCMCIA slots available.

Can I use any kind of digital video camera?
SIMI products generally work with all DV cameras as long as they have an IEEE-1394 (Firewire / iLink) output and are compatible with Microsoft DirectX

Can the cameras be from different manufacturers?
Yes

How many cameras are necessary to calculate 3D data?
At minimum 2 digital cameras are necessary for 3D data acquisition.

How are the cameras connected to the computer system?
All cameras are connected using FireWire Interface cables.

I have an IEEE-1394 FireWire PCMCIA Card that has 2 adapter ports. Will the software recognize the different 1394 ports on the 1 PCMCIA card, or do I have to have 2 individual PCMCIA cards to control 2 DV cameras?
You have to use 2 individual PCMCIA cards in order to capture synchronized with 2 digital video cameras. Most notebooks already have a FireWire port built in, that means that synchronized capturing with 3 digital cameras on a notebook is possible.

What file format does the program save the captured videos in?
The program saves the files in an editable AVI file that can be shared between different computers.

Can I use analog cameras?
Yes, with the use of frame grabber cards.

Can I use high-speed cameras from Redlake, etc.?
Yes

Besides capturing live images, can images also be downloaded from a DV tape?
Yes

Can repeaters be purchased at Radio Shack to extend cable length?
Yes

Does the software allow extraction of the individual fields in the JVC-9800 high-speed mode? Can it re-arrange them consecutively at 240 Hz?
Yes

What is the resolution of the images when captured in high-speed mode at 240 Hz with the JVC-9800? My understanding is that in high-speed mode, the CCD splits the image either horizontally or vertically for 120 fps, and both horizontally and vertically for 240 fps. I assume that this cuts the resolution of the picture in half as the camera is only using half of the CCD for each split. I am curious how much the increased resolution of the progressive scan CCD is offset by the reduction of the resolution in the high-speed mode.
About 308x184 pixels (NTSC frame: 720x480)
(so it is less than half the size...)

You claim that individual frames captured from high-speed JVC cameras (240 Hz) can be displayed. However, the JVC GR-DVL9800 video camera only has a max shutter speed of 1/250 sec, which is not fast enough for our needs. Can you suggest any other video-cameras that have a higher-speed capability (>60 fps) and a higher shutter speed (1/1000 sec)? I have a Canon Optura that records at 30 fps in progressive scan, but I do not believe that it can display frames at a higher speed.
The Basler A600 series operates at up to 100 frames per second at full 656 x 491 resolution.
The Basler A300 series operates at up to 80 frames per second at full 658 x 494 resolution.

What pixel size and frequency do PAL and NTSC have?
PAL: 768x576, 25 full frames = 50 Fields/s
NTSC: 640x480, 29, 96 full frames = 59, 92 Fields/s

CALIBRATION

Do I need to calibrate the space?
Yes, for a 3D calibration, at least 8 calibration points are necessary. The more calibration points the higher the accuracy.

DIGITIZING/TRACKING

Is there an automatic digitizing/tracking?
Yes, in SIMI°Motion or SIMI°MotionCapture 3D, not so in SIMI°MoStill or SIMI°TwinnerPro

How is tracking done?
With SIMI°Motion or SIMI°MotionCapture you can use colored, black and white or reflective markers. Once you have identified the marker, the system tracks the points automatically as long as they are visible. If they are hidden, the system stops and you can estimate where they are and click manually or you leave the frames out until they are visible again. Then you have to identify them again and let the system track them automatically again. With special marker sets you can calculate joint centers, moments and forces. In a 3D view (skeletal, stick or other models) you can trace single points and superimpose them. You also can trace joint centers or centers of gravity of single segments.

How many markers can I use?
You may us up to 200 markers.

What size are the markers?
The size can be as small as < 1mm and - depending on the distance of the cameras to the object - as big as you want. The system tracks pixels. The minimum pixel requirement for tracking is 16 pixels (area of 4x4 pixels).

What type of markers can be used with SIMI°Motion or SIMI°MotionCapture 3D?
Users may choose between reflective or non-reflective markers, white or colored markers. Colored markers are good when capturing a small area and markers are close together.

Does your system require active markers?
No, all markers are passive.

Do I have to wear a special suit?
No.

How are the markers attached to the body?
The markers may be easily attached using double sided tape or may be fixed to a bodysuit.

How good must the contrast between the markers and the background be for automatic tracking? How is automatic tracking done? Is it via centroids or iterative prediction?
The human eye can not always detect good contrast between the markers, but the software does because it looks through a number of color spaces to detect the shape of the marker. The most important thing is to have clear information of the shape of the marker. If the color of the marker merges with the background color, you may have a problem. The algorithm is a dynamic algorithm, which means that the marker template is updated and adjusted frame by frame.

SOFTWARE

What operation system can be used?
WINDOWS XP or WINDOWS 2000

Does the software run on Macintosh?
No

Can we install the software on 1 portable computer for capturing purposes and on 4-6 desktop computers so students can analyze images during a lab session?
Yes, with additional licenses and security hard locks.

Does the program work for any IEEE 1394 PCI card?
Yes.

Are there any measurement and drawing tools associated with SIMI software? Are there crude tools for measuring 2D planar joint angles and distances?
SIMI°Twinner Pro and SIMI°MoStill do measure 2D planar joint angles and distances, but measurements are only possible in still images.

SIMI°Motion is also able to do this, but the focus is on 2D and 3D analysis (time series analysis, not just still images).

SIMI°Motion is also available in a 2D version.

What analysis tools are available in SIMI°Motion?
The tools available are 3D Kinematics (displacements, velocity, acceleration, angles, angular velocity, and angular acceleration), Inverse Kinematics (joint center, rotation angle) and Inverse Dynamics (moment, force, power). Calculation of the center of gravity is a feature as well as many more.

Does the software package synchronize recording and/or playback of two or more cameras at once? SIMI°Motion claims to have capture software that allows operation of all cameras by pressing a single button for start and stop, but is the video actually synchronized to the same clock.
All cameras are captured at the same time and the system knows the exact time difference between the cameras (frames/fields and the small offset between two cameras since they are not hardware-synchronized, and shutter-open time is not exactly identical). After capturing, you can cut the videos (all clips at the same time) to extract only the part of the video you are really interested in.

The remaining small offset (less than 17 ms for NTSC) is used during 3D reconstruction.

The video images themselves are not synchronized better than ½ field (8.4 ms).

The video "clock"-signal is made by each camera. Two cameras will have a shift due to clock inaccuracies of max. 1ms.

How are the cameras triggered to begin sampling? Is pre-trigger sampling available (i.e., camera samples to memory until triggered and then saves data from a period of time before sampling)?
The cameras are frame-synchronized, which means that you have according to frame 1 of camera one the next neighbored frame of camera 2. Digital camcorders can not be genlocked, but our software calculates the shift between those neighbored frames and knows the time when camera 2 should have taken a frame which would have been time-synchronized to camera 1. That information is integrated in the 3D calculation and increases the accuracy of the calculated data to an accuracy of 1ms.

Is there a video-mix capability incorporated into one of the products?
Yes, in SIMI°Twinner Pro.

In what format can SIMI Motion export data?
C3D, ASCII, TXT, BVH, BVA, 3ds max, Lightwave, Maya, Poser.

Does your system support foot pressure distribution measurement?
Yes, plug-Ins for TekScan, Novel, Parotec or Medilogic in SIMI Motion or SIMI MoStill are available.

The ability to calculate joint angles using Euler or Cardan angles would also be desirable.
The module 'Inverse Dynamics' is able to calculate cardan angles. The calculation of euler angles is being developed.

Do you also have analysis software to identify onset and termination of movements?
Yes, you may use the phaser module for defining the onset and the terminations of movements.

HARDWARE

Does your system require any specific hardware?
No, all components (computer, cameras, accessories, etc.) are off-the-shelf products and can be easily purchased.

What are the hardware requirements?
Optimal configuration (Desktop)
Pentium IV, > 2 GHz
2 hard drives, > 80 GB (speed 7200 rpm)
512 Megabytes RAM
WINDOWS 2000 or WINDOWS XP

Optimal configuration (Notebook)
Pentium IV, > 2 GHz
Hard disk, 40 GB
512 Megabytes RAM
WINDOWS 2000 or WINDOWS XP

A/D COLLECTION

How many channels does the system support?
The system supports 128 (for force plate, EMG, goniometric, etc)

Does the software allow synchronized playback of video files along with a measured signal (in time series form)? Better yet, does the software have a scroll bar that runs through the time series signal showing where it is with the associated synchronized video files? I am assuming that I had synchronized data (either from a triggered LED or a microphone for impact event) that I fed into the audio channel of one of the cameras at the appropriate time (post-processed).
For analog data collection, SIMI°Motion is the solution. Data will be visible in diagrams and all windows are synchronized with the "scrollbar". SIMI°Motion will also show the audio-track of a given AVI (for synchronization purposes only).

Analog data can be collected with an A/D-converter from Data Translation or National Instruments.

Can video capture be automatically synchronized to additional measurements like analog data input from force plates? How is the information synchronized and what sort of hardware is required to perform this operation?
You can acquire analog data from force plates, EMG, goniometers etc. synchronized with the same computer.

Kistler and AMTI force plates have special support (calculation of moments, center of pressure, etc.).

Is force data time-synchronized with the digital images of the master camera? How?
Yes, the system detects the actual time of the first video frame and shifts the analog data in time in order to synchronize it.

Must the sampling rate be a multiple of the field rate (60 Hz)?
No, all diagrams and calculations are time-based (in seconds) not sample-based, so all data like video, force-platforms, pressure distribution etc. can have different frequencies

Are the channels sampled simultaneously (burst mode) or synchronously?
All A/D cards have a specific sampling rate. It is often 200000 samples per second (200 KS/s). All selected channels are sampled with this frequency.

Example: You want to acquire 16 channels with 1000 Hz. Then the channels are sampled one after another with 1/200000 s time delay => all 16 channels are sampled within 16/200000 = 0.00008 seconds. This is considerably less than the selected frequency of 1000 Hz = 0.001 seconds.

Would a National Instruments NI DAQPad-6020E for USB work with your system?
Both products are supported and equally recommended (100 KS/s, 12 Bit resolution).

PRECISION OF DLT COEFFICIENTS

Are residuals calculated between the re-predicted and known control point coordinates?
No, but we have similar information in our 3D calibration validation module. The difference to the re-predicted calibration points is given in pixels which is more understandable for the user.

What algorithm do you use for calculating 3D data from your video?
DLT (digital linear transformation), which is a linear transformation of 2D camera data into a 3D space. In addition we use DLT OPT which enhances the accuracy of the system. Also included, is a calibration check to verify the accuracy of calibration.

READING FILES FROM CD

I understand that images are captured live to the hard drive for reasons of speed. Can the files be transferred so that students can work off a read/writeable CD? In other words, can they read the image files from CD and save the data files to the CD from within SIMI?
SIMI°Motion will use any AVI or MPEG file that can be opened and controlled with the Windows Media-Player. You are not limited to files which have been captured within SIMI°Motion. During the capture process the images are written to a reserved space on your hard disk (capture file). After that the user can select a portion of the captured sequence (cropping) and save that to any destination drive (local hard disk, removable disk, network etc.). There is a system called "Direct-CD" which makes CDs behave like a hard disk. Files can be transferred to the CD without using CD burning software. You could use Direct-CD within SIMI°Motion as well. Alternatively you could burn all AVI files to a CD or DVD with your favorite application (Nero, WinOnCD etc.). You will then have to re-assign the AVI files in SIM°Motion since path names have changed using a special feature called "resource manager".

SERVICE

Do you provide training?
YES

Do you provide support?
YES

Do you deliver turn key solutions?
YES