Visual Assessment of Camouflaged Targets with Different Background Similarities

Abstract

The study investigated the effectiveness of different camouflage designs using a computational image quality index. Camouflaged human targets were presented on a natural landscape and the targets were designed to be similar to the landscape background with different levels of background similarity as estimated by the image index. The targets were presented in front of the observer (central 0 degrees) or at different angles in the left (-7 degrees, -14 degrees, -21 degrees) or right (+7 degrees, +14 degrees, +21 degrees) visual fields. The observer had to detect the target using peripheral vision if the target appeared in the left and right visual fields. The camouflage effectiveness was assessed by detection hit rates, detection times, and subjective ratings on detection confidence and task difficulty. The study showed that the psychophysical measures correlated well with the image similarity index, suggesting a potentially more efficient camouflage effectiveness assessment tool if the relationship between the psychophysical results and the index can be quantified in the future.

Urban camouflage assessment through visual search and computational saliency

“…These metrics allowed us to distinguish between good (patterns 1, 8, 9, 11 in Fig. 4), medium (patterns 5, 6, 10) and poorly performing patterns (2,3,4,7). The pattern based on the design method presented here (pattern number 9) combined the overall lowest detection probability with an intermediate search time, indicating that the TNO design method can produce effective camouflage patterns.…”

“…[1][2][3][4][5] Traditionally camouflage design was (and still is) largely based on intuition and aesthetics, and was performed by industrial designers and (especially in the beginning) by artists 6 (incl. cubists such as Georges Braque).…”

Climate Change and Spatiotemporal Distributions of Vector-Borne Diseases in Nepal – A Systematic Synthesis of Literature

“…A review of elevation-dependent warming and its possible causes in four high mountain regions–the Swiss Alps, the Colorado Rocky Mountains, the Tibetan Plateau/Himalayas, and the Tropical Andes–showed variation in the trends of extreme temperatures suggesting the need for a comprehensive study analysing the minimum and maximum temperatures separately for all mountain regions together to better understand elevation-based warming in mountains [122]. The highly varied topography over short distances and poor coverage of observational datasets especially in mountain regions render spatiotemporal climate change projections for Nepal difficult and any projections must be interpreted with caution [123].…”

Search by photo methodology for signature properties assessment by human observers

“…Our choice of placing all targets in identical position in a scene also reduces the image edging effect on the target rankings. It has been reported that observers tend to focus on the center of an image [17], resulting in differences in detection performance by the observers [2,17,19].…”

“…Photo-simulation by using human observers as an assessment method of camouflage effectiveness has been used in various forms in the recent decades [1][2][3][4]. Other methodologies have also been tested out, involving video surveillance [5], simulation of human vision [6][7][8][9][10][11], similarity measures of target-background by image analysis techniques [2,11], assessment by simulation of target vehicles against different backgrounds [12], and image sequences taken by approaching sensors [13].…”