Real Time Implementation of the Omnidirectional Vision Construction Algorithm of the Panoptic Camera

The visual system of the flying insects is the source of inspiration for the presented hardware vision system. The faceted eyes of a common fly provide it with omnidirectional vision, egomotion and depth estimation. Utilizing the concept of faceted eyes, an omnidirectional camera is realized by layering CMOS image sensors over the surface of a hemispherical structure. This system is referred to as the Panoptic camera and it has two distinguished features. First, it is an omnidirectional camera capable of recording light information from any direction around its center. Second, it is a polydioptric system where each CMOS facet consists of a CMOS camera with a distinct focal plane; hence the full system is a multiple aperture camera

Real-Time Computational Gigapixel Multi-Camera Systems

The standard cameras are designed to truthfully mimic the human eye and the visual system. In recent years, commercially available cameras are becoming more complex, and offer higher image resolutions than ever before. However, the quality of conventional imaging methods is limited by several parameters, such as the pixel size, lens system, the diffraction limit, etc. The rapid technological advancements, increase in the available computing power, and introduction of Graphics Processing Units (GPU) and Field-Programmable-Gate-Arrays (FPGA) open new possibilities in the computer vision and computer graphics communities. The researchers are now focusing on utilizing the immense computational power offered on the modern processing platforms, to create imaging systems with novel or significantly enhanced capabilities compared to the standard ones. One popular type of the computational imaging systems offering new possibilities is a multi-camera system. This thesis will focus on FPGA-based multi-camera systems that operate in real-time. The aim of themulti-camera systems presented in this thesis is to offer a wide field-of-view (FOV) video coverage at high frame rates. The wide FOV is achieved by constructing a panoramic image from the images acquired by the multi-camera system. Two new real-time computational imaging systems that provide new functionalities and better performance compared to conventional cameras are presented in this thesis. Each camera system design and implementation are analyzed in detail, built and tested in real-time conditions. Panoptic is a miniaturized low-cost multi-camera system that reconstructs a 360 degrees view in real-time. Since it is an easily portable system, it provides means to capture the complete surrounding light field in dynamic environment, such as when mounted on a vehicle or a flying drone. The second presented system, GigaEye II , is a modular high-resolution imaging system that introduces the concept of distributed image processing in the real-time camera systems. This thesis explains in detail howsuch concept can be efficiently used in real-time computational imaging systems. The purpose of computational imaging systems in the form of multi-camera systems does not end with real-time panoramas. The application scope of these cameras is vast. They can be used in 3D cinematography, for broadcasting live events, or for immersive telepresence experience. The final chapter of this thesis presents three potential applications of these systems: object detection and tracking, high dynamic range (HDR) imaging, and observation of multiple regions of interest. Object detection and tracking, and observation of multiple regions of interest are extremely useful and desired capabilities of surveillance systems, in security and defense industry, or in the fast-growing industry of autonomous vehicles. On the other hand, high dynamic range imaging is becoming a common option in the consumer market cameras, and the presented method allows instantaneous capture of HDR videos. Finally, this thesis concludes with the discussion of the real-time multi-camera systems, their advantages, their limitations, and the future predictions

Reconfigurable Forward Homography Estimation System for Real-Time Applications

Image processing and computer vision algorithms extensively use projections, such as homography, as one of the processing steps. Systems for homography calculation usually observe homography as an inverse problem and provide an exact solution. However, the systems processing larger resolution images cannot meet inherently tight real-time constraints. Look-up table based systems provide an option for forward homography solutions, but they require large memory availability. Recent compressed look-up table methods reduce the memory requirements at the expense of lower peak signal-to-noise-ratio. In this work, we present a forward homography estimation algorithm which provides higher image quality than compressed look-up table methods. The algorithm is based on bounding the homography error, and neglecting the pixels out of the determined bound. The presented FPGA implementation of the estimation system requires a small amount of hardware, and no memory storage. The prototype system project an image frame onto a spherical surface at 295 Mpixels/s rate which is, up to our knowledge, currently the fastest homography system

Performance Optimization and FPGA Implementation of Real-Time Tone Mapping

This brief analyzes the performance of the hardware-based tone mapping operators for compression of high dynamic range images. The bottlenecks of a tone mapping system are determined and a high-performance field programmable gate array (FPGA) implementation of an operator is introduced. The operator utilizes polynomial mapping technique, adaptive to the pixel values; hence preserving high contrast areas. The technique is further optimized for the presented resource-efficient FPGA implementation. We show that the timing optimization does not reduce the image quality, by obtaining high peak signal-to-noise ratio of the resulting images. The timing comparison to the similar implementations shows 2.5 times increase in the achieved throughput, irrespective of the hardware platform

Real-time FPGA implementation of linear blending vision reconstruction algorithm using a spherical light field camera

A custom spherical light-field camera used as a polydioptric system where imagers are distributed over a spherical geometry, each having its own vision of the surrounding and distinct focal plane. The spherical light-field camera is also an omnidirectional camera which records light information from any direction around its center. A novel linear blending technique is presented for vision reconstruction of a virtual observer located inside the spherical geometry of this camera. This blending technique improves the output quality of the reconstructed vision with respect to the ordinary stitching technique. A novel pixel gridding scheme is presented for rectangular displaying of the reconstructed vision induced from the spherical light field camera. This gridding technique preserve the correct size of objects when mapped on the spherical geometry of the Panoptic system. A hardware architecture based on FPGAs with the real-time implementation of the linear blending algorithm and the new pixel gridding scheme of the spherical light-field camera are presented along with imaging results

Multi-Camera Platform for Panoramic Real-Time HDR Video Construction and Rendering

High dynamic range (HDR) images are usually obtained by capturing several images of the scene at different exposures. Previous HDR video techniques adopted the same principle by stacking HDR frames in time domain. We designed a new multi-camera platform which is able to construct and render HDR panoramic video in real-time, with 1024 × 256 resolution and a frame rate of 25 fps. We exploit the overlapping fields-of-view between the cameras with different exposures to create an HDR radiance map. We propose a method for HDR frame reconstruction which merges the previous HDR imaging techniques with the algorithms for panorama reconstruction. The developed FPGA-based processing system is able to reconstruct the HDR frame using the proposed method and tone map the resulting image using a hardware-adapted global operator. The measured throughput of the system is 245 MB/s, which is, up to our knowledge, among the fastest HDR video processing systems

Uticaj međuredne kultivacije i vremena osnovne obrade zemljišta na prinos soje

Timely and correct application of agro technical measures in the production of soybean is a condition for obtaining high and stable yields, both in favorable years and in unfavorable years for production. The aim of this research is to examine the influence of interrelated cultivation and the time of basic soil treatment on soybean yield. One intermediate cultivation increases the yield by an average of 2.45%, by 2.08% for autumn cultivation and 2.82% for spring basic land cultivation. Two intercropping cultivars increase the average yield by 3.54%, by 2.59% for autumn harvesting and 4.49% for spring basic soil cultivation. Spring ground cultivation reduced the yield of 21.33%, and the decrease ranged from 6.45% in favorable year, to 36.21% in the unfavorable year for soybean production.Pravovremena i pravilna primena agrotehničkih mera u proizvodnji soje je uslov za dobijanje visokih i stabilnih prinosa, kako u povoljnim godinama, tako i u nepovoljnim godinama za proizvodnju. Cilj ovih istraživanja je sagledavanje uticaja međuredne kultivacije i vremena osnovne obrade zemljišta na prinos soje. Jedna međuredna kultivacija povećava prinos u proseku za 2,45% i to za 2,08% kod jesenje osnovne obrade i 2,82% kod prolećne osnovne obrade zemljišta. Dve međuredne kultivacije povećavaju prinos soje u proseku za 3,54% i to za 2,59% kod jesenje osnovne obrade i 4,49% kod prolećne osnovne obrade zemljišta. Prolećna osnovna obrada zemljišta smanjuje prinos 21,33%, a smanjenje se kretalo od 6,45% u povoljnoj godini, do 36,21% u nepovoljnoj godini za proizvodnju soje

Image Blending in a High Frame Rate FPGA-based Multi-Camera System

Panoptic is a custom spherical light field camera used as a polydioptric system where imagers are distributed over a hemispherical surface, each having its own vision of the surroundings and a distinct focal plane. The spherical light field camera records light information from any direction around its center. This paper revises previously developed Nearest Neighbor and Linear blending techniques. Novel Gaussian blending and Restricted Gaussian blending techniques for vision reconstruction of a virtual observer located inside the spherical geometry are presented. These new blending techniques improve the output quality of the reconstructed image with respect to the ordinary stitching techniques and simpler image blending algorithms. A comparison of the developed blending algorithms is also given in this paper. A hardware architecture based on Field Programmable Gate Arrays (FPGA) enabling the real-time implementation of the blending algorithms is presented, along with the imaging results and resource utilization comparison. A recorded omnidirectional video is attached as a supplementary material

Review paper Being a vegetarian: health benefits and hazards

Although their anatomical features disclose the herbivorous nature of humans, an omnivorous diet can be considered an evolutionary advantage that has supported human survival. Over recent decades, vegetarianism has significantly increased in developed countries due to the support of scientific research, emerging supermarkets and restaurants, and easy-to-access soy products and healthy foods. According to current knowledge, vegetarian diets are associated with significantly lower prevalence of obesity and lower risk of cardiovascular mortality. However, while the overall risk of cancer is slightly lower in vegetarians, the findings regarding the location and type of cancer that can be prevented by vegetarian diets are inconclusive. In addition to this, it remains unclear whether health benefits of vegetarian diets can be attributed to the avoidance of meat, or to the increased intake of dietary fibre, n-6 fatty acids, vitamins C, B9 and E, potassium, magnesium and phyto-chemicals, or to both of these factors. As a vegetarian diet becomes more restrictive, intake of adequate daily energy and of n-3 fatty acids, essential amino acids, vitamin B12, zinc, calcium and iron becomes more difficult to achieve, which is particularly challenging in children who have higher nutrient requirements relative to body weight than adults