|
Checker Shadow Illusion
The checker shadow illusion is an optical illusion published by Edward H. Adelson, professor of vision science at MIT in 1995. Description The image depicts a checkerboard with light and dark squares, partly shadowed by another object. The optical illusion is that the area labeled A appears to be a darker color than the area labeled B. However, within the context of the two-dimensional image, they are of identical brightness, ''i.e.'', they would be printed with identical mixtures of ink, or displayed on a screen with pixels of identical color. Related illusions Whilst being one of the most well-known contrast illusions, there are similar effects which cause two regions of identical color to appear differently depending on context: * The Cornsweet illusion creates a boundary between two identically-shaded regions with a discontinuous gradient, resulting in the opposing sides appearing to be different. * The Chubb illusion evokes this effect by surrounding zones with others ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Checker Shadow Illusion
The checker shadow illusion is an optical illusion published by Edward H. Adelson, professor of vision science at MIT in 1995. Description The image depicts a checkerboard with light and dark squares, partly shadowed by another object. The optical illusion is that the area labeled A appears to be a darker color than the area labeled B. However, within the context of the two-dimensional image, they are of identical brightness, ''i.e.'', they would be printed with identical mixtures of ink, or displayed on a screen with pixels of identical color. Related illusions Whilst being one of the most well-known contrast illusions, there are similar effects which cause two regions of identical color to appear differently depending on context: * The Cornsweet illusion creates a boundary between two identically-shaded regions with a discontinuous gradient, resulting in the opposing sides appearing to be different. * The Chubb illusion evokes this effect by surrounding zones with others ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contrast Effect
A contrast effect is the enhancement or diminishment, relative to normal, of perception, cognition or related performance as a result of successive (immediately previous) or simultaneous exposure to a stimulus of lesser or greater value in the same dimension. (Here, normal perception, cognition or performance is that which would be obtained in the absence of the comparison stimulus—i.e., one based on all previous experience.) Perception example: A neutral gray target will appear lighter or darker than it does in isolation when immediately preceded by, or simultaneously compared to, respectively, a dark gray or light gray target. Cognition example: A person will appear more or less attractive than that person does in isolation when immediately preceded by, or simultaneously compared to, respectively, a less or more attractive person. Performance example: A laboratory rat will work faster, or slower, during a stimulus predicting a given amount of reward when that stimulus and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Constancy
Color constancy is an example of subjective constancy and a feature of the human color perception system which ensures that the perceived color of objects remains relatively constant under varying illumination conditions. A green apple for instance looks green to us at midday, when the main illumination is white sunlight, and also at sunset, when the main illumination is red. This helps us identify objects. Color vision Color vision is how we perceive the objective color, which people, animals and machines are able to distinguish objects based on the different wavelengths of light reflected, transmitted, or emitted by the object. In humans, light is detected by the eye using two types of photoreceptors, Cone cells, cones and Rod cells, rods, which send signals to the visual cortex, which in turn processes those colors into a subjective perception. Color constancy is a process that allows the brain to recognize a familiar object as being a consistent color regardless of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychophysics
Psychophysics quantitatively investigates the relationship between physical stimuli and the sensations and perceptions they produce. Psychophysics has been described as "the scientific study of the relation between stimulus and sensation" or, more completely, as "the analysis of perceptual processes by studying the effect on a subject's experience or behaviour of systematically varying the properties of a stimulus along one or more physical dimensions". ''Psychophysics'' also refers to a general class of methods that can be applied to study a perceptual system. Modern applications rely heavily on threshold measurement, ideal observer analysis, and signal detection theory. Psychophysics has widespread and important practical applications. For example, in the study of digital signal processing, psychophysics has informed the development of models and methods of lossy compression. These models explain why humans perceive very little loss of signal quality when audio and video sign ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Slate Group
The Slate Group, legally The Slate Group, LLC, is an American online publishing entity established in June 2008 by Graham Holdings Company. Among the publications overseen by The Slate Group are ''Slate'' and '' ForeignPolicy.com''. The creation of The Slate Group was announced by Donald Graham, the chairman and CEO of The Washington Post Company, in a press release on June 4, 2008. Its mission was stated as developing and managing a family of web-only magazines. The release also announced that Slate Group was expected to work closely with Washingtonpost.Newsweek Interactive in the areas of advertising sales, technology and marketing services. In 2014, The Slate Group had around 121 employees and reported more than 25 million unique visitors and more than 120 million page views per month on average.Graham Holdings2014 Annual Report(availablon GHCO.com Through a share in the French company E2J2 SAS and other support, The Slate Group is involved in the French-language websites ''S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slate (magazine)
''Slate'' is an online magazine that covers current affairs, politics, and culture in the United States. It was created in 1996 by former '' New Republic'' editor Michael Kinsley, initially under the ownership of Microsoft as part of MSN. In 2004, it was purchased by The Washington Post Company (later renamed the Graham Holdings Company), and since 2008 has been managed by The Slate Group, an online publishing entity created by Graham Holdings. ''Slate'' is based in New York City, with an additional office in Washington, D.C. ''Slate'', which is updated throughout the day, covers politics, arts and culture, sports, and news. According to its former editor-in-chief Julia Turner, the magazine is "not fundamentally a breaking news source", but rather aimed at helping readers to "analyze and understand and interpret the world" with witty and entertaining writing. As of mid-2015, it publishes about 1,500 stories per month. A French version, ''slate.fr'', was launched in February 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chubb Illusion
The Chubb illusion is an optical illusion or error in visual perception in which the apparent contrast of an object varies substantially to most viewers depending on its relative contrast to the field on which it is displayed. These visual illusions are of particular interest to researchers because they may provide valuable insights in regard to the workings of human visual systems. An object of low-contrast visual texture surrounded by a field of uniform visual texture appears to have higher contrast than when presented on a field of high-contrast texture. This illusion was observed by Charles Chubb and colleagues and published in 1989. An empirical explanation of the Chubb illusion was published by Lotto and Purves in 2001. Discovery Chubb and his colleagues researched this illusion by showing various combinations of foreground objects and background fields to human test subjects and asking them to rate the sharpness of the visual contrast in each foreground object. They found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cornsweet Illusion
The Cornsweet illusion, also known as the Craik–O'Brien–Cornsweet illusion or the Craik–Cornsweet illusion, is an optical illusion that was described in detail by Tom Cornsweet in the late 1960s. Kenneth Craik and Vivian O'Brien had made earlier observations in a similar vein. The original version of the illusion involved a rapidly spinning black-and-white disk, painted in a way that would create the appearance of a gradient effect when in motion. An equivalent static version of illusion is composed of a gray rectangle where the left half fades to a lighter shade as it approaches a vertical center line, and the right half fades to a darker gray approaching the same line. As a result, the whole left half of the rectangle appears lighter than the right half, but in fact the brightness of both areas is exactly the same. This can be seen by blacking out the region containing the edge. This phenomenon is similar to the phenomenon of simultaneous contrast and Mach bands, bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color
Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associated with objects or materials based on their physical properties such as light absorption, reflection, or emission spectra. By defining a color space, colors can be identified numerically by their coordinates. Because perception of color stems from the varying spectral sensitivity of different types of cone cells in the retina to different parts of the spectrum, colors may be defined and quantified by the degree to which they stimulate these cells. These physical or physiological quantifications of color, however, do not fully explain the psychophysical perception of color appearance. Color science includes the perception of color by the eye and brain, the origin of color in materials, color theory in art, and the physics of electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Checkerboard
A checkerboard (American English) or chequerboard (British English; see spelling differences) is a board of checkered pattern on which checkers (also known as English draughts) is played. Most commonly, it consists of 64 squares (8×8) of alternating dark and light color, typically green and buff (official tournaments), black and red (consumer commercial), or black and white (printed diagrams). An 8×8 checkerboard is used to play many other games, including chess, whereby it is known as a chessboard. Other rectangular square-tiled boards are also often called checkerboards. Games and puzzles using checkerboards Martin Gardner featured puzzles based on checkerboards in his November 1962 Mathematical Games column in Scientific American. A square checkerboard with an alternating pattern is used for games including: * Amazons * Chapayev * Chess and some of its variants (see chessboard) * Czech draughts * Draughts, also known as checkers * Fox games * Frisian draughts * Gounki * In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1995
File:1995 Events Collage V2.png, From left, clockwise: O.J. Simpson is O. J. Simpson murder case, acquitted of the murders of Nicole Brown Simpson and Ronald Goldman from the 1994, year prior in "The Trial of the Century" in the United States; The Great Hanshin earthquake strikes Kobe, Japan, killing 5,000-6,000 people; The Unabomber Manifesto is published in several U.S. newspapers; Gravestone, Gravestones mark the victims of the Srebrenica massacre near the end of the Bosnian War; Windows 95 is launched by Microsoft for Personal computer, PC; The first exoplanet, 51 Pegasi b, is discovered; Space Shuttle Atlantis docks with the Space station Mir in a display of U.S.-Russian cooperation; The Alfred P. Murrah Federal Building in Oklahoma City is Oklahoma City bombing, bombed by Domestic terrorism in the United States, domestic terrorists, killing 168., 300x300px, thumb rect 0 0 200 200 O. J. Simpson murder case rect 200 0 400 200 Great Hanshin earthquake, Kobe earthquake rect 400 0 6 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
