Performance of a path tracing task using stereo and motion based depth cues

Stereoscopic displays have a number of properties that could be advantageous in the field of medical diagnosis. The aim of the current study is to get a better understanding of the relative importance of motion based depth cues (object motion, movement parallax) and stereoscopic disparity on the performance of a path tracing task, representative of angiographic visualizations. To date, these cues have not frequently been combined in a single study that would allow a direct comparison of their effects. In this paper, we report on an experiment where we measured the effectiveness of motion-based cues and stereoscopic disparity in terms of completion time, number of errors, perceived workload and perceived discomfort. Results revealed that both object motion and movement parallax enhanced performance in terms of number of correct answers. However, object motion was superior to motion parallax on self-report of mental workload and visual comfort. Stereoscopic disparity significantly decreased completion times when combined with object motion or movement parallax. On accuracy, no effect of stereo was found

User centered design of gesture-based interaction technology

This paper discusses the user-centered design process of developing a gesture-based interaction technology aimed at interacting with three-dimensional displays at short working distances (e.g., at arm’s length). First, we explored the range and variability of gestures that come natural for users when interacting with 3D displays. The next section describes the challenges encountered when implementing the preferred gestures into the gesture tracking technology. In the final section the gesture tracker is evaluated and compared against the currently dominant interaction paradigm – the computer mouse. Results of the evaluation are used for the design of future prototypes of the technology

Performance of a path tracing task using stereo and motion based depth cues

Stereoscopic displays have a number of properties that could be advantageous in the field of medical diagnosis. The aim of the current study is to get a better understanding of the relative importance of motion based depth cues (object motion, movement parallax) and stereoscopic disparity on the performance of a path tracing task, representative of angiographic visualizations. To date, these cues have not frequently been combined in a single study that would allow a direct comparison of their effects. In this paper, we report on an experiment where we measured the effectiveness of motion-based cues and stereoscopic disparity in terms of completion time, number of errors, perceived workload and perceived discomfort. Results revealed that both object motion and movement parallax enhanced performance in terms of number of correct answers. However, object motion was superior to motion parallax on self-report of mental workload and visual comfort. Stereoscopic disparity significantly decreased completion times when combined with object motion or movement parallax. On accuracy, no effect of stereo was found

Effectiveness of stereoscopic displays in medicine : a review

In this paper we review empirical studies concerning the effectiveness of stereoscopic displays in medicine. The domains covered in this review are: diagnosis, pre-operative planning, minimally invasive surgery (MIS) and training/teaching. For diagnosis, stereoscopic viewing of medical data has been shown to improve the sensitivity of tumor detection in breast imaging, and to improve the visualization of internal structures in 3D ultrasound. For MRI and CT data, where images are frequently rendered in 3D perspective, the added value of binocular depth has not yet been convincingly demonstrated. For MIS, stereoscopic displays decrease surgery time and increase accuracy of surgical procedures when the resolution of the stereoscopic displays is comparable to that of 2D displays. Training and surgical planning already use computer simulations; more research however is needed to assess the potential benefits of stereoscopic displays in those applications. Overall, there is a clear need for more empirical evidence that quantifies the added value of stereoscopic displays in medical domains

How people are critical to the success of Big Data

A buzz has emerged around Big Data: an emerging field that is concerned with capturing, storing, combining, visualizing and analysing large and diverse sets of data. Realizing the societal benefits of Data Driven Innovations requires that the innovations are used and adopted by people. In fact like in many other technological innovations people are critical to the success of Big Data; people are in many cases where the data is collected, people are in charge of interpreting and visualising the information that can be found in the data, and people are, in the end, also the actors that need to change their behaviour in order to make a change in 'the real world'. www.humanfactors.n

Evaluating stereoscopic displays : both efficiency measures and perceived workload sensitive to manipulations in binocular disparity

Stereoscopic displays are known to offer a number of key advantages in visualizing complex 3D structures or datasets. The large majority of studies that focus on evaluating stereoscopic displays for professional applications use completion time and/or the percentage of correct answers to measure potential performance advantages. However, completion time and accuracy may not fully reflect all the benefits of stereoscopic displays. In this paper, we argue that perceived workload is an additional valuable indicator reflecting the extent to which users can benefit from using stereoscopic displays. We performed an experiment in which participants were asked to perform a visual path-tracing task within a convoluted 3D wireframe structure, varying in level of complexity of the visualised structure and level of disparity of the visualisation. The results showed that an optimal performance (completion time, accuracy and workload), depend both on task difficulty and disparity level. Stereoscopic disparity revealed a faster and more accurate task performance, whereas we observed a trend that performance on difficult tasks stands to benefit more from higher levels of disparity than performance on easy tasks. Perceived workload (as measured using the NASA-TLX) showed a similar response pattern, providing evidence that perceived workload is sensitive to variations in disparity as well as task difficulty. This suggests that perceived workload could be a useful concept, in addition to standard performance indicators, in characterising and measuring human performance advantages when using stereoscopic displays

User experience of gesture based interfaces : a comparison with traditional interaction methods on pragmatic and hedonic qualities

In this study gesture-based interaction technologies are compared with device-based interaction methods (Mouse and Wii) in terms of pragmatic and hedonic quality. Results show that both pragmatic and hedonic qualities are important indicators when evaluating interaction technologies, as they yield complementary and sometimes differing results. More embodied interaction (gestures and Wii) reveals higher scores in terms of hedonic quality and fun than mouse-based interaction, however, body fatigue increases when using more embodied styles of interaction

Stereoscopic displays in the medical domains: a review of perception and performance effects

In this paper we review empirical studies that investigate performance effects of stereoscopic displays for medical applications. We focus on four distinct application areas: diagnosis, pre-operative planning, minimally invasive surgery (MIS) and training/teaching. For diagnosis, stereoscopic displays can augment the understanding of complex spatial structures and increase the detection of abnormalities. Stereoscopic viewing of medical data has proven to increase the detection rate in breast imaging. A stereoscopic presentation of noisy and transparent images in 3D ultrasound results in better visualization of the internal structures, however more empirical studies are needed to confirm the clinical relevance. For MRI and CT, where images are frequently rendered in 3D perspective, the added value of binocular depth has not yet been convincingly demonstrated. For MIS, stereoscopic displays can decrease surgery time and increase accuracy of surgical procedures. Performance of surgical procedures is similar when high resolution 2D displays are compared with lower resolution stereoscopic displays, indicating an image quality improvement for stereoscopic displays. Training and surgical planning already use computer simulations in 2D, however more research is needed to the benefit of stereoscopic displays in those applications. Overall there is a clear need for more empirical evidence that quantifies the added value of stereoscopic displays in medical domains, such that the medical community will have ample basis to invest in stereoscopic displays in all or some of the described medical applications

Stereoscopic displays in the medical domains: a review of perception and performance effects

In this paper we review empirical studies that investigate performance effects of stereoscopic displays for medical applications. We focus on four distinct application areas: diagnosis, pre-operative planning, minimally invasive surgery (MIS) and training/teaching. For diagnosis, stereoscopic displays can augment the understanding of complex spatial structures and increase the detection of abnormalities. Stereoscopic viewing of medical data has proven to increase the detection rate in breast imaging. A stereoscopic presentation of noisy and transparent images in 3D ultrasound results in better visualization of the internal structures, however more empirical studies are needed to confirm the clinical relevance. For MRI and CT, where images are frequently rendered in 3D perspective, the added value of binocular depth has not yet been convincingly demonstrated. For MIS, stereoscopic displays can decrease surgery time and increase accuracy of surgical procedures. Performance of surgical procedures is similar when high resolution 2D displays are compared with lower resolution stereoscopic displays, indicating an image quality improvement for stereoscopic displays. Training and surgical planning already use computer simulations in 2D, however more research is needed to the benefit of stereoscopic displays in those applications. Overall there is a clear need for more empirical evidence that quantifies the added value of stereoscopic displays in medical domains, such that the medical community will have ample basis to invest in stereoscopic displays in all or some of the described medical applications

Evaluating stereoscopic displays : both efficiency measures and perceived workload sensitive to manipulations in binocular disparity

Stereoscopic displays are known to offer a number of key advantages in visualizing complex 3D structures or datasets. The large majority of studies that focus on evaluating stereoscopic displays for professional applications use completion time and/or the percentage of correct answers to measure potential performance advantages. However, completion time and accuracy may not fully reflect all the benefits of stereoscopic displays. In this paper, we argue that perceived workload is an additional valuable indicator reflecting the extent to which users can benefit from using stereoscopic displays. We performed an experiment in which participants were asked to perform a visual path-tracing task within a convoluted 3D wireframe structure, varying in level of complexity of the visualised structure and level of disparity of the visualisation. The results showed that an optimal performance (completion time, accuracy and workload), depend both on task difficulty and disparity level. Stereoscopic disparity revealed a faster and more accurate task performance, whereas we observed a trend that performance on difficult tasks stands to benefit more from higher levels of disparity than performance on easy tasks. Perceived workload (as measured using the NASA-TLX) showed a similar response pattern, providing evidence that perceived workload is sensitive to variations in disparity as well as task difficulty. This suggests that perceived workload could be a useful concept, in addition to standard performance indicators, in characterising and measuring human performance advantages when using stereoscopic displays