03 November 2008 | Print page |
SMI’s iView X RED System measures how humans perceive objects, and what attracts our gaze, with extreme accuracy.SensoMotoric Instruments (SMI) is a world leader in dedicated computer vision applications, developing and marketing eye & gaze tracking systems and OEM solutions for a wide range of applications. Founded in 1991 as a spin-off from academic research, SMI was the first company to offer a commercial, vision-based 3D eye tracking solution. SMI now has over 15 years of experience in developing application-specific solutions in close collaboration with its clients. The company serves its customers around the globe from offices in Teltow, near Berlin, Germany and Needham near Boston, USA, backed by a network of trusted local partners in many countries. SMI’s products combine a maximum of performance and usability with the highest possible quality, resulting in high-value solutions for customers.
“The eyes are the window to the soul“, folk wisdom tells us. Science and economics know it, too, and both fields have exhibited a keen interest in determining how humans perceive their surroundings, what attracts our gaze, and what we tend to overlook. Be it research on behavior patterns, psychology, pedagogical evaluation of learning materials, ergonomics of software and web sites or analysis of the effects of advertising – the scientific evaluation of human eye movement across a particular image has a number of possible applications. The field of marketing in particular invests a great deal in this area: how should a display window be arranged to draw passing customers’ notice? What should product packaging look like to stand out from the competition on a crowded supermarket shelf? How can a print or broadcast advertisement be structured to best get its call to action across? Advertisers and agencies are extremely eager for well-founded answers to these tricky questions.
iView X RED from SMI Maps Eye Gaze Movement
With its iView X RED, SMI has developed an innovative, portable system that can precisely track and analyze the course of a test subject’s gaze upon a particular motif, such as an advertisement.
The device itself comes in the form of a compact sensor unit flexible enough to be installed to work in a stand for printed matter (such as a newspaper or magazine), a screen, or even a projector. The test subject then sits in front of the device, about 50 to 70 cm (about 20 to 25 inches) away, and views the test image. The test subject is free to move in his or her seat and wears no apparatus on the head or eyes, thus ensuring comfort, freedom from disruption, and the ability to completely commit to the experiment. The system is even able to work with subjects who wear glasses or contact lenses.
The sensor unit, with its integrated digital camera, is connected to a PC whose imaging software then analyzes the captured data in real time: the test subject’s head, eyes and pupils are automatically recognized and even the smallest eye movements are tracked in relation to the test image. A mapping of the gaze’s path across the image is then generated: what first attracts the viewer’s gaze? How long does the test subject stare at a particular element — text or a prominent motif? In which order are the various elements of the image “read”, so to speak? The iView X RED measures all of this precisely and provides a graphic representation on the image being evaluated.
The Requirements: High Resolution and Fast Frame Rate
A high resolution of the camera is necessary to enable precise pupil locating across an entire image of a face. A high image rate is also crucial for the measurement exactitude, registering and recording each and every eye movement down to the smallest degree.
The iView X RED System, in contrast to many other eye tracking solutions, can also be used outside the laboratory and its standardized lighting, with no head or eye gear required for the test subject, which requires extremely high image quality under all lighting conditions.
Customer Satisfaction at AVT: Customized Camera Solution
A digital camera from Allied Vision Technologies is built into the sensor unit. This particular camera was developed especially to meet SMI’s needs, offering a high enough resolution to enable precise pupil locating across an entire image of a face. Thanks to its rapid IEEE 1394b FireWire interface and the image reduction to the AOI of the eye region, the camera captures the images at a rate of 50 frames per second. The so-called “smart features” of AVT’s digital camera optimize image quality even within the camera before the data is transmitted to the computer. Capitalizing on these functions, such as Look-up Tables, Shading Correction, Anti-Smear and Binning, ensures a sharp, optimized image for evaluation.
“Thanks to Allied Vision Technologies’ customized solution, we have found the ideal camera for this ambitious application”, exclaimed Dr. Christian Lappe, Sales & Marketing Manager of Eye and Gaze Tracking Systems at SMI. “This camera meets not only the basic conditions for eye tracking in terms of resolution and frame rate, but the built-in functions for image optimization facilitate evaluation by the system as well, even without any apparatus on the test subject’s head and under variable ambient light conditions”.
Practical Implementation: From Marketing to Psychology Research
iView X RED has already been used internationally in a number of applications – from marketing research institutes to website and advertising optimization as well as in university psychology research labs. Beyond pure eye movement evaluation for research purposes, the information it establishes can also be used for the active operation of computers or machines — helping disabled individuals to interact with the world using their eye movements, for example. The Eye Tracking System from SMI, together with AVT camera technology, proves how digital imaging can move beyond the fields of industrial automation, research, science, medicine or marketing to even more spectacular advances.