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Rolling Shutter Effect
Rolling shutter describes the process of image capture in which a still picture (in a still camera) or each frame of a video (in a video camera) is captured not by taking a snapshot of the entire scene at a single instant in time but rather by scanning across the scene rapidly, vertically, horizontally or rotationally. Thus, not all parts of the image of the scene are recorded at the same instant – however, during playback, the entire image of the scene is displayed at once, as if it represents a single instant in time. This produces predictable distortions of fast-moving objects or rapid flashes of light, referred to as rolling shutter effect. This process in contrast with global shutter in which the entire frame is captured at the same instant. The rolling shutter can be either focal-plane shutter#Two-curtain shutters, mechanical or Shutter (photography)#Electronic shutter, electronic. The advantage of this electronic rolling shutter is that the image sensor can continue t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rolling Shutter Effect Animation
Rolling is a Motion (physics)#Types of motion, type of motion that combines rotation (commonly, of an Axial symmetry, axially symmetric object) and Translation (geometry), translation of that object with respect to a surface (either one or the other moves), such that, if ideal conditions exist, the two are in contact with each other without sliding (motion), sliding. Rolling where there is no sliding is referred to as ''pure rolling''. By definition, there is no sliding when there is a frame of reference in which all points of contact on the rolling object have the same velocity as their counterparts on the surface on which the object rolls; in particular, for a frame of reference in which the rolling plane is at rest (see animation), the instantaneous velocity of all the points of contact (for instance, a generating line segment of a cylinder) of the rolling object is zero. In practice, due to small deformations near the contact area, some sliding and energy dissipation occurs. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matchmoving
In visual effects, match moving is a technique that allows the insertion of 2D elements, other live action elements or CG computer graphics into live-action footage with correct position, scale, orientation, and motion relative to the photographed objects in the shot. It also allows for the removal of live action elements from the live action shot. The term is used loosely to describe several different methods of extracting camera motion information from a motion picture. Also referred to as motion tracking or camera solving, match moving is related to rotoscoping and photogrammetry. Match moving is sometimes confused with motion capture, which records the motion of objects, often human actors, rather than the camera. Typically, motion capture requires special cameras and sensors and a controlled environment (although recent developments such as the Kinect camera and Apple's Face ID have begun to change this). Match moving is also distinct from motion control photography, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cameras
A camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photography and videography, cameras have played a significant role in the progression of visual arts, media, entertainment, surveillance, and scientific research. The invention of the camera dates back to the 19th century and has since evolved with advancements in technology, leading to a vast array of types and models in the 21st century. Cameras function through a combination of multiple mechanical components and principles. These include exposure control, which regulates the amount of light reaching the sensor or film; the lens, which focuses the light; the viewfinder, which allows the user to preview the scene; and the film or sensor, which captures the image. Several types of camera exist, each suited to specific uses and offering unique cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wagon-wheel Effect
The wagon-wheel effect (alternatively called stagecoach-wheel effect) is an optical illusion in which a spoked wheel appears to rotate differently from its true rotation. The wheel can appear to rotate more slowly than the true rotation, it can appear stationary, or it can appear to rotate in the opposite direction from the true rotation (reverse rotation effect). The wagon-wheel effect is most often seen in film or television depictions of stagecoaches or wagons in Western movies, although recordings of any regularly spoked rotating object will show it, such as helicopter rotors, aircraft propellers and car rims. In these recorded media, the effect is a result of temporal aliasing. It can also commonly be seen when a rotating wheel is illuminated by flickering light. These forms of the effect are known as ''stroboscopic effects'': the original smooth rotation of the wheel is visible only intermittently. A version of the wagon-wheel effect can also be seen under continuous i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strip Photography
Strip photography, or slit photography, is a photographic technique of capturing a two-dimensional image as a sequence of one-dimensional images over time, in contrast to a normal photo which is a single two-dimensional image (the full field) at one point in time. A moving scene is recorded, over a period of time, using a camera that observes a narrow strip rather than the full field. If the subject is moving through this observed strip at constant speed, they will appear in the finished photo as a visible object. Stationary objects, like the background, will be the same the whole way across the photo and appear as stripes along the time axis; see examples on this page. The image can be understood as a collection of thin vertical or horizontal strips patched together, hence the name. Digital sensors do produce discrete strips of pixels that are captured and arranged one line at a time. In film photography, the image is instead produced continuously, so there are no discrete strip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadratrix Of Hippias
The quadratrix or trisectrix of Hippias (also called the quadratrix of Dinostratus) is a curve which is created by a uniform motion. It is traced out by the crossing point of two Line (geometry), lines, one moving by translation (geometry), translation at a uniform speed, and the other moving by rotation (geometry), rotation around one of its points at a uniform speed. An alternative definition as a parametric curve leads to an equivalence between the quadratrix, the image of the Lambert W function, and the graph of the function y=x\cot x. The discovery of this curve is attributed to the Greek sophist Hippias, Hippias of Elis, who used it around 420 BC in an attempt to solve the Angle trisection, angle trisection problem, hence its name as a trisectrix. Later around 350 BC Dinostratus used it in an attempt to solve the problem of squaring the circle, hence its name as a quadratrix. Dinostratus's theorem, used in this attempt, relates an endpoint of the curve to the value of . Bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Event Camera
An event camera, also known as a neuromorphic camera, silicon retina, or dynamic vision sensor, is an imaging sensor that responds to local changes in brightness. Event cameras do not capture images using a shutter as conventional (frame) cameras do. Instead, each pixel inside an event camera operates independently and asynchronously, reporting changes in brightness as they occur, and staying silent otherwise. Functional description Event camera pixels independently respond to changes in brightness as they occur. Each pixel stores a reference brightness level, and continuously compares it to the current brightness level. If the difference in brightness exceeds a threshold, that pixel resets its reference level and generates an event: a discrete packet that contains the pixel address and timestamp. Events may also contain the polarity (increase or decrease) of a brightness change, or an instantaneous measurement of the illumination level, depending on the specific sensor mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Artifactual Value
Digital artifactual value, a preservation term, is the intrinsic value of a digital object, rather than the informational content of the object. Though standards are lacking, born-digital objects and digital representations of physical objects may have a value attributed to them as artifacts. Intrinsic value in analog materials With respect to analog or non-digital materials, artifacts are determined to have singular research or archival value if they possess qualities and characteristics that make them the only acceptable form for long-term preservation.The National Archives Committee on Intrinsic Value. "Intrinsic Value In Archival Material." Staff Information Paper No. 21, 1982. These qualities and characteristics are commonly referred to as the item's intrinsic value and form the basis upon which digital artifactual value is currently evaluated. Artifactual value based on this idea is predicated upon the artifact's originality, faithfulness, fixity, and stability. The intri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afton Down
Afton Down is a chalk downland, chalk down near the village of Freshwater, Isle of Wight, Freshwater on the Isle of Wight. Afton Down faces Compton Bay directly to the west, while Freshwater is approximately one mile north. It was the site of the Isle of Wight Festival 1970, where the ''Guinness Book of Records'' estimates 600,000 to 700,000, and possibly 800,000 people, flocked to see the musical talents of Emerson, Lake & Palmer, Free (band), Free, Live at the Isle of Wight Festival 1970 (The Who album), The Who, The Doors, Ten Years After, Taste (Irish band), Taste, and Jimi Hendrix. In keeping with the native flora of Compton Bay, a variety of hardy plants grow on the down. Large European gorse bushes grow on the cliff, with the shelter they provide allowing other plants such as wild cabbage and bird's foot trefoil to grow. The Isle of Wight's County flowers of the United Kingdom, county flower, the pyramidal orchid (''Anacamptis pyramidalis''), also grows here, along with P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aliasing
In signal processing and related disciplines, aliasing is a phenomenon that a reconstructed signal from samples of the original signal contains low frequency components that are not present in the original one. This is caused when, in the original signal, there are components at frequency exceeding a certain frequency called Nyquist frequency, f_s / 2, where f_s is the sampling frequency ( undersampling). This is because typical reconstruction methods use low frequency components while there are a number of frequency components, called aliases, which sampling result in the identical sample. It also often refers to the distortion or artifact that results when a signal reconstructed from samples is different from the original continuous signal. Aliasing can occur in signals sampled in time, for instance in digital audio or the stroboscopic effect, and is referred to as temporal aliasing. Aliasing in spatially sampled signals (e.g., moiré patterns in digital images) is referre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propellor With Rolling-shutter Artifact
A propeller (often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working fluid such as water or air. Propellers are used to pump fluid through a pipe or duct, or to create thrust to propel a boat through water or an aircraft through air. The blades are shaped so that their rotational motion through the fluid causes a pressure difference between the two surfaces of the blade by Bernoulli's principle which exerts force on the fluid. Most marine propellers are screw propellers with helical blades rotating on a propeller shaft with an approximately horizontal axis. History Early developments The principle employed in using a screw propeller is derived from stern sculling. In sculling, a single blade is moved through an arc, from side to side taking care to keep presenting the blade to the water at the effective angl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
