Low complexity FPGA based background subtraction technique for thermal imagery

Embedded smart camera systems are gaining popularity for a number of real world surveillance applications. However, there are still challenges, i.e. variation in illumination, shadows, occlusion, and weather conditions while employing the vision algorithms in outdoor environments. For safety-critical surveillance applications, the visual sensors can be complemented with beyond-visual-range sensors. This in turn requires analysis, development and modification of existing imaging techniques. In this work, a low complexity background modelling and subtraction technique has been proposed for thermal imagery. The proposed technique has been implemented on Field Programmable Gate Arrays (FPGAs) after in-depth analysis of different sets of images, characterizing poor signal-to-noise ratio challenges, e.g. motion of high frequency background objects, temperature variation and camera jitter etc. The proposed technique dynamically updates the background on pixel level and requires a single frame storage as opposed to existing techniques. The comparison of this approach with two other approaches show that this approach performs better in different environmental conditions. The proposed technique has been modelled in Register Transfer Logic (RTL) and implementation on the latest FPGAs shows that the design requires less than 1 percent logics, 47 percent block RAMs, and consumes 91 mW power consumption on Artix-7 100T FPGA

Paraustrorhynchus smeetsae Lin & Reygel & Feng & Chen & Tessens & Van Steenkiste & Schockaert & Artois & Wang 2019, n. sp.

<i>Paraustrorhynchus smeetsae</i> Artois, Reygel, Tessens & Van Steenkiste n. sp. <p> <i>Paraustrorhynchus</i> n. sp. in Tessens <i>et al</i>. 2014</p> <p>(Fig. 6)</p> <p> <b>Locality.</b> Goa (India), AIT Beach (15°34’2.8”N, 73°44’28.5”E), protected bay with coarse sand with shell gravel, specimens collected by B. Tessens and N. Van Steenkiste, 3 rd and 12 th December 2008.</p> <p> <b>Material examined.</b> Several animals studied alive, five whole mounts (three suitable for observation of hard structures), one whole mount designated holotype (FMNH http://id.luomus.fi/KV.607), the others paratype (HU 591–594) two additional serially-sectioned (sagitally) specimens (HU 595–596).</p> <p> <b>Etymology.</b> Named after Prof. Karen Smeets (UHasselt), in appreciation of her dedication towards the UHasselt research group.</p> <p> <b>Diagnosis.</b> Species of <i>Paraustrorhynchus</i> with a dorsal dark-blue pigment pattern consisting of a transversal band dorsally from the pharynx, separated from a mid-dorsal band in the second body half. Prostate stylet type II double walled, ± 47 µm long, funnel-shaped, curved, with two fin-like structures just proximal from the curve. Outer stylet with proximal longitudinal slit; inner stylet lacking in the proximal 1/3 of the stylet. Prostate stylet type III ± 26 µm, consisting of a common proximal plate ± 38 µm broad, from which two arms depart. Both arms with broad serrated distal ends, ± 24 µm and 16 µm wide respectively, are largely overlapping.</p> <p> <b>Description.</b> The animals are opaque, with scattered light-brown pigment and a prominent blue pigment pattern (Fig. 6 A, B) consisting of a transversal band dorsally from the pharynx separated from a longitudinal band in the caudal body half. The pigmentation consists of small granules under the body wall. Its relation to specific cells is not clear, but the pattern is similar in the observed animals. Depending on the degree of contraction and squeezing, internal structures such as the copulatory bulb may disrupt the pigment pattern. The animals have two eyes and are 300–700 µm long ( = 530 µm; n = 5; measured on whole mounts).</p> <p> The internal organisation, including that of the male and female atrial system, corresponds completely to that of <i>P. isoldeae</i> (see above). The stylet type II (Fig. 6 D, E) is 45–49 µm long (x‾= 47 µm; n = 3). It is a doublewalled, curved tube. Near the distal, pointed end the stylet is twisted over a short distance. The inner stylet can be followed over the whole length of the outer stylet except in the distal twist and in the proximal 1/3 of the stylet. At one side, the proximal 1/3 of the outer stylet shows a longitudinal slit, which broadens at the level of the proximal end of the inner stylet, leaving the inner stylet apparently uncovered at this side. At about its midpoint, the outer stylet is provided with two small, fin-like structures. In one whole mount, one of the fin-like structures is missing; probably it is not visible due to compression and orientation of the stylet. The prostate stylet type III (Fig. 6 G, F) consists of two arms proximally connected to a single folded broad plate (36–41 µm wide; x‾ = 38 µm; n = 3). The ventral arm widens to a broad plate (20–29 µm wide; x‾= 24 µm; n = 3), and has ± 3/4 of the its distal rim serrated. The dorsal arm ends in a less broad plate (15–17 µm wide; x‾= 16 µm; n = 3), which has a completely serrated distal rim. Both arms are almost equal in length and determine the length of the stylet type III (24–30 µm; x‾= 26 µm; n = 3). Measurements of the length and especially the width in the middle of the stylet depends on the inclination of the proximal plate and the position of both arms due to the compression of the preserved specimens.</p>Published as part of <i>Lin, Yitao, Reygel, Patrick, Feng, Weitao, Chen, Jiajia, Tessens, Bart, Van Steenkiste, Niels W. L., Schockaert, Ernest R., Artois, Tom J. & Wang, Antai, 2019, Four new species of the genus Paraustrorhynchus (Rhabdocoela: Kalyptorhynchia: Polycystididae), pp. 357-373 in Zootaxa 4550 (3)</i> on pages 366-367, DOI: 10.11646/zootaxa.4550.3.4, <a href="http://zenodo.org/record/2625481">http://zenodo.org/record/2625481</a&gt

Four new species of the genus Paraustrorhynchus (Rhabdocoela: Kalyptorhynchia: Polycystididae)

Lin, Yitao, Reygel, Patrick, Feng, Weitao, Chen, Jiajia, Tessens, Bart, Van Steenkiste, Niels W. L., Schockaert, Ernest R., Artois, Tom J., Wang, Antai (2019): Four new species of the genus Paraustrorhynchus (Rhabdocoela: Kalyptorhynchia: Polycystididae). Zootaxa 4550 (3): 357-373, DOI: https://doi.org/10.11646/zootaxa.4550.3.

Paraustrorhynchus sinensis Lin & Reygel & Feng & Chen & Tessens & Van Steenkiste & Schockaert & Artois & Wang 2019, n. sp.

<i>Paraustrorhynchus sinensis</i> Wang & Lin n. sp. <p>(Figs. 3–4)</p> <p> <b>Locality.</b> Same as <i>P. shenda</i> <b>n. sp.</b></p> <p> <b>Material examined.</b> One whole mount designated holotype: PLA-Po61. Paratypes PLA-Po062–064, three whole mounts; PLA-Po065-1–065-3, three whole mounts of prostate stylet type II and III; PLA-Po066-1–066-6, six serially-sectioned (sagittal) specimens and PLA-Po066-7, one serially-sectioned (horizontal) individual.</p> <p> <b>Etymology.</b> The species name refers to the country where it was discovered.</p> <p> <b>Diagnosis.</b> Species of <i>Paraustrorhynchus</i> with a mid-dorsal dark-blue pigment stripe. Prostate stylet type II ± 75 µm long, curved, outer stylet with proximal longitudinal slit. Prostate style type III ± 38 µm long, ± 40 µm wide proximally, ±12 µm wide in the middle and ±30 µm distally, consisting of a common proximal plate with two arms. Both arms broadened distally, one being broader than the other one, which is more or less boot-shaped. Distal rim of both arms provided with teeth.</p> <p> <b>Description.</b> Habitus and internal morphology identical to that of <i>P. shenda</i> <b>n. sp.</b> (Fig. 1A,B, 4A), including the dorsal blue longitudinal pigment stripe. The prostate stylet type II is 7 0–80 µm long (x‾ = 75 µm; n = 3). It has a longitudinal slit ending at the stylet's midpoint. The stylet tapers gradually to end in a sharp distal point (Fig 3 A–C, 4B). The proximal 3/4 of the stylet curves slightly and the distal 1/4 makes a 100° turn. The inner stylet can be followed over the whole length of the outer stylet, except in the proximal 1/4 of the stylet. The outer stylet has a funnel-shaped base, measuring 8–11 µm in width (n = 2). The funnel of the inner stylet narrows abruptly at about halfway along the length of the outer stylet and broadens again, gradually alongside the outer stylet. The prostate stylet type III consists of three parts: a proximal triangular plate with two extending long arms. Measurements of the prostate stylet type III (n = 2): length 33–42 µm; proximal width 38–42 µm; width in the middle 10–13 µm; distal width: 25–34 µm. The two arms, one boot-shaped and one plate-like, are curved towards each other and broaden distally. The distal ends of both arms are serrated, the plate-like arm shows large teeth (up to 7 µm in length) (Fig. 3 D–I, 4C).</p>Published as part of <i>Lin, Yitao, Reygel, Patrick, Feng, Weitao, Chen, Jiajia, Tessens, Bart, Van Steenkiste, Niels W. L., Schockaert, Ernest R., Artois, Tom J. & Wang, Antai, 2019, Four new species of the genus Paraustrorhynchus (Rhabdocoela: Kalyptorhynchia: Polycystididae), pp. 357-373 in Zootaxa 4550 (3)</i> on page 362, DOI: 10.11646/zootaxa.4550.3.4, <a href="http://zenodo.org/record/2625481">http://zenodo.org/record/2625481</a&gt