China
Africa
Explore chapters and articles related to this topic
Visual Inspection Technology and Data Coding Systems
Published in Justin Starr, Water and Wastewater Pipeline Assessment Technologies, 2021
Many pole cameras tout incredibly large zoom ratios – more than 400x! This is disingenuous. Many do offer 30–36x optical zoom capability coupled with a 10–12x digital zoom. These zooms are not created equal. Optical zooming relies on adjustments to the lenses in a camera system in order to effectively increase the magnification of an object. Both resolution and sharpness are maintained, so long as the image is focused. Digital zoom crops out a portion of the pixels on the screen, and resizes the image to fit. It does not enable the display of additional information, as cropping and resizing could easily be performed on a computer after the inspection. When purchasing a pole camera, special attention should be paid to the optical zoom functionality.
5G Edge-Based Video Surveillance in Smart Cities
Published in Zoran S. Bojkovic, Dragorad A. Milovanovic, Tulsi Pawan Fowdur, 5G Multimedia Communication, 2020
Video surveillance camera converts the visual light image (focused by the camera lens) into an electrical time-varying video signal for later presentation on a monitor display and/or permanent recording on a video recorder. The lens collects the reflected light from the scene and focuses it onto the camera image sensor. The sensor converts the light image into a time-varying electronic signal. The camera electronics processes the information from the sensor and forms the video signal. If it is IP camera, video signal is digitized, compressed and packed into IP stream over Ethernet interface. IP packets are sent to a viewing monitor by two-wire unshielded twisted-pair, wireless or other IP transmission system.
Sensors for Autonomous Vehicles in Infrastructure Inspection Applications
Published in Diego Galar, Uday Kumar, Dammika Seneviratne, Robots, Drones, UAVs and UGVs for Operation and Maintenance, 2020
Diego Galar, Uday Kumar, Dammika Seneviratne
A visible spectrum camera operates on about a 390 nm (3.9 μm) to 750 nm (7.5 μm) wavelength. There are two main categories: digital still cameras and machine vision cameras (including surveillance and webcam).
Online glass confidence map building using laser rangefinder for mobile robots
Published in Advanced Robotics, 2020
Jun Jiang, Renato Miyagusuku, Atsushi Yamashita, Hajime Asama
Monocular cameras are low-cost sensors, that do require preprocessing and can be a burden to low-spec systems. For SLAM, typically, features such as lines or corners are extracted from the images captured by the camera [7]. Then, a map is created using these features, for the robot to localize itself within this map. Unfortunately, similarly to LRFs, cameras have an inherent disability for detecting glass. Cameras capture images by detecting the light reflected through their lenses by the objects in the environment. Cameras can not detect glass because depending on the glass properties and the natural illumination of the environment, light either does not reflect, making the cameras see through the glass and captures the images of the objects behind it. Or, the glass acts similarly to a mirror and reflects all the light from the objects located behind the camera. Figure 4 illustrates both previously described cases.
Identification of defective weld and quality monitoring in manual metal arc welding process using surface level image features
Published in Welding International, 2022
Bipul Das, Aman Dwivedi, Mehdi Mehtab Mirad
A machine vision system cannot function without a clear image, so it is very important to guarantee a steady environment for the camera to capture the images. Digital cameras have an image sensor that is responsible for capturing the image, equivalent to a film on a traditional camera. The most used image sensor type in digital cameras is CMOS (complementary metal-oxide-semiconductor). The captured images are very similar to a picture of the scene as seen by a human eye. The CMOS camera should have the following specifications, such as high resolution, low power consumption, improved colour concept, and low light sensor.