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79-588: It is named after its inventor, Bryce Bayer of Eastman Kodak . Bayer is also known for his recursively defined matrix used in ordered dithering . Alternatives to the Bayer filter include both various modifications of colors and arrangement and completely different technologies, such as color co-site sampling , the Foveon X3 sensor , the dichroic mirrors or a transparent diffractive-filter array. Bryce Bayer 's patent (U.S. Patent No. 3,971,065) in 1976 called

158-439: A halftone picture or ray tracing a checkered plane (the latter being a special case of aliasing , due to undersampling a fine regular pattern). This can be overcome in texture mapping through the use of mipmapping and anisotropic filtering . The drawing on the upper right shows a moiré pattern. The lines could represent fibers in moiré silk, or lines drawn on paper or on a computer screen. The nonlinear interaction of

237-565: A bachelor's degree in engineering physics from the University of Maine in 1951, Bayer moved to Rochester, New York , to work as a research scientist at Eastman Kodak , where he would remain until his retirement in 1986. At Kodak he met Joan Fitzgerald, a fellow researcher; they were married in 1954. Bayer pursued further studies at the University of Rochester , from which he earned a master's degree in industrial statistics in 1960. In 1974, while working for Kodak Research Labs (KRL), Bayer

316-678: A crucial role in storing, enhancing, and printing digital images. As a leading scientist in the Information Technology Laboratory within the Physics Division of the Kodak Research Laboratories (KRL), Bryce demonstrated, in the early eighties, that computers could greatly enhance image quality. For example, he showed a large print of a dock scene made from a very small Disc camera negative. The image looked like it had been made from

395-518: A daughter, Janet. Bayer died on November 13, 2012, in Bath, Maine , of "a long illness related to dementia," his son Douglas told The New York Times . Moir%C3%A9 In mathematics, physics, and art, moiré patterns ( UK : / ˈ m w ɑː r eɪ / MWAH -ray , US : / m w ɑː ˈ r eɪ / mwah- RAY , French: [mwaʁe] ) or moiré fringes are large-scale interference patterns that can be produced when

474-426: A fixed direction (say, the x-coordinate) in the paper plane, in the form f = 1 + sin ⁡ ( k x ) 2 {\displaystyle f={\frac {1+\sin(kx)}{2}}} where the presence of 1 keeps the function positive definite, and the division by 2 prevents function values greater than 1. The quantity k represents the periodic variation (i.e., spatial frequency) of

553-440: A given point on the paper as the average (i.e. the arithmetic mean) of each pattern's opacity at that position, which is half their sum, and, as calculated, does not exceed 1. (This choice is not unique. Any other method to combine the functions that satisfies keeping the resultant function value within the bounds [0,1] will also serve; arithmetic averaging has the virtue of simplicity—with hopefully minimal damage to one's concepts of

632-417: A group in the areas of computer programming, applied statistics, information science, and applied mathematics. The group developed an automated way to selectively disseminate information to users based on their interest profiles and on their interest level feedback. This process is like processes used today by Google and Amazon. In the mid-1960s, there was a group of similar size to Bryce's group working down

711-500: A hero for me." Parulski told the Democrat and Chronicle that he felt "very lucky to have worked with Bryce, starting on my very first day at Kodak....Bryce was so modest and unassuming, it took me years to realize what a genius he really was." Parulski added "that Bayer's invention is the key reason we have cameras that are compact yet provide sharp-looking pictures." Bayer's contribution to photography also included algorithms that play

790-426: A moiré pattern, and show one way (of many possible ways) these patterns and the moiré effect can be rendered mathematically. The visibility of these patterns is dependent on the medium or substrate in which they appear, and these may be opaque (as for example on paper) or transparent (as for example in plastic film). For purposes of discussion we shall assume the two primary patterns are each printed in greyscale ink on

869-420: A mosaic) and arrangements of three separate CCDs (one for each color) doesn't need demosaicing. On June 14, 2007, Eastman Kodak announced an alternative to the Bayer filter: a colour-filter pattern that increases the sensitivity to light of the image sensor in a digital camera by using some panchromatic cells that are sensitive to all wavelengths of visible light and collect a larger amount of light striking

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948-601: A much larger 35 mm negative. One could see the braids in the rope sitting on the dock. About fifteen years earlier, in the mid-sixties, he developed a way to encrypt information in a way that the code could not be broken by others. Again, he developed this as a leader within the KRL Information Technology Laboratory. At the time, he was also studying Shannon's work on information theory and entropy, Shannon-Fano coding to use shorter codes for more frequent words or signals, etc. Bryce led

1027-412: A partially opaque ruled pattern with transparent gaps is overlaid on another similar pattern. For the moiré interference pattern to appear, the two patterns must not be completely identical, but rather displaced, rotated, or have slightly different pitch. Moiré patterns appear in many situations. In printing, the printed pattern of dots can interfere with the image. In television and digital photography,

1106-471: A pattern on an object being photographed can interfere with the shape of the light sensors to generate unwanted artifacts. They are also sometimes created deliberately; in micrometers , they are used to amplify the effects of very small movements. In physics, its manifestation is wave interference like that seen in the double-slit experiment and the beat phenomenon in acoustics . The term originates from moire ( moiré in its French adjectival form),

1185-433: A pattern that appears when superposing two transparent layers containing correlated opaque patterns. Line moiré is the case when the superposed patterns comprise straight or curved lines. When moving the layer patterns, the moiré patterns transform or move at a faster speed. This effect is called optical moiré speedup. More complex line moiré patterns are created if the lines are curved or not exactly parallel. Shape moiré

1264-408: A person is wearing a shirt or jacket of a particular weave or pattern, such as a houndstooth jacket. This is due to interlaced scanning in televisions and non-film cameras, referred to as interline twitter . As the person moves about, the moiré pattern is quite noticeable. Because of this, newscasters and other professionals who regularly appear on TV are instructed to avoid clothing which could cause

1343-580: A personal computer. The cheaper the camera, the fewer opportunities to influence these functions. In professional cameras, image correction functions are completely absent, or they can be turned off. Recording in Raw-format provides the ability to manually select demosaicing algorithm and control the transformation parameters, which is used not only in consumer photography but also in solving various technical and photometric problems. Demosaicing can be performed in different ways. Simple methods interpolate

1422-423: A screen some distance away. This phase moiré effect and the classical moiré effect from opaque lines are two ends of a continuous spectrum in optics, which is called the universal moiré effect. The phase moiré effect is the basis for a type of broadband interferometer in x-ray and particle wave applications. It also provides a way to reveal hidden patterns in invisible layers. Line moiré is one type of moiré pattern;

1501-484: A sensor having all green-sensitive elements. "The pattern is very simple," Ken Parulski, former chief scientist for Kodak's digital camera division, told The New York Times after Bayer's death. "There are twice as many green elements as red or blue because this mimics the way the human eye provides the sharpest overall color image." Parulski added that although dozens of other patterns have since been devised, including some by Parulski himself, "the Bayer pattern has stood

1580-432: A type of textile , traditionally made of silk but now also made of cotton or synthetic fiber , with a rippled or "watered" appearance. Moire, or "watered textile", is made by pressing two layers of the textile when wet. The similar but imperfect spacing of the threads creates a characteristic pattern which remains after the fabric dries. In French, the noun moire is in use from the 17th century, for "watered silk". It

1659-409: A white sheet, where the opacity (e.g., shade of grey) of the "printed" part is given by a value between 0 (white) and 1 (black) inclusive, with ⁠ 1 / 2 ⁠ representing neutral grey. Any value less than 0 or greater than 1 using this grey scale is essentially "unprintable". We shall also choose to represent the opacity of the pattern resulting from printing one pattern atop the other at

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1738-428: Is d and the side opposite to the angle α is p ). The pale lines correspond to the small diagonal of the rhombus. As the diagonals are the bisectors of the neighbouring sides, we can see that the pale line makes an angle equal to ⁠ α / 2 ⁠ with the perpendicular of each pattern's line. Additionally, the spacing between two pale lines is D , half of the long diagonal. The long diagonal 2 D

1817-552: Is also known as Tetracell by Samsung , 4-cell by OmniVision , and Quad CFA (QCFA) by Qualcomm . On March 26, 2019, the Huawei P30 series were announced featuring RYYB Quad Bayer, with the 4x4 pattern featuring 4x blue, 4x red, and 8x yellow. On February 12, 2020, the Samsung Galaxy S20 Ultra was announced featuring Nonacell CFA. Nonacell CFA is similar to Bayer filter, however adjacent 3x3 pixels are

1896-401: Is an acoustic version of the moiré effect in the one dimension of time: the original two notes are still present—but the listener's perception is of two pitches that are the average of and half the difference of the frequencies of the two notes. Aliasing in sampling of time-varying signals also belongs to this moiré paradigm. Consider two patterns with the same step p , but the second pattern

1975-579: Is another name for edge blurring that occurs in an on/off pattern along an edge. This effect occurs when the demosaicing algorithm averages pixel values over an edge, especially in the red and blue planes, resulting in its characteristic blur. As mentioned before, the best methods for preventing this effect are the various algorithms which interpolate along, rather than across image edges. Pattern recognition interpolation, adaptive color plane interpolation, and directionally weighted interpolation all attempt to prevent zippering by interpolating along edges detected in

2054-547: Is behind nearly every digital image captured today." According to the Rochester Democrat and Chronicle, Bayer's work on the filter "helped pave the way for the development of the first working digital camera a year later." Steve Sasson, co-inventor of the first digital camera, told the Rochester newspaper "that Bayer's contributions were not only pioneering but prophetic." Sasson added that "Bryce has always been

2133-414: Is easily shown that A = k 1 + k 2 2 {\displaystyle A={\frac {k_{1}+k_{2}}{2}}} and B = k 1 − k 2 2 . {\displaystyle B={\frac {k_{1}-k_{2}}{2}}.} This function average, f 3 , clearly lies in the range [0,1]. Since the periodic variation A

2212-442: Is higher. The raw output of Bayer-filter cameras is referred to as a Bayer pattern image. Since each pixel is filtered to record only one of three colors, the data from each pixel cannot fully specify each of the red, green, and blue values on its own. To obtain a full-color image, various demosaicing algorithms can be used to interpolate a set of complete red, green, and blue values for each pixel. These algorithms make use of

2291-556: Is inevitable, but in favorable circumstances the pattern is "tight"; that is, the spatial frequency of the moiré is so high that it is not noticeable. In the graphic arts, the term moiré means an excessively visible moiré pattern. Part of the prepress art consists of selecting screen angles and halftone frequencies which minimize moiré. The visibility of moiré is not entirely predictable. The same set of screens may produce good results with some images, but visible moiré with others. Moiré patterns are commonly seen on television screens when

2370-490: Is most important to sharpness”. In March 1975, Kodak filed a patent application, titled "Color imaging array", with Bayer as the sole inventor. The patent, which issued as U.S. patent 3,971,065 in July 1976, describes color patterns having luminance (e.g. green) elements arranged in a checkerboard pattern, which provides uniform luminance sampling in both the horizontal and vertical directions. The Bayer color filter array pattern

2449-463: Is one type of moiré pattern demonstrating the phenomenon of moiré magnification. 1D shape moiré is the particular simplified case of 2D shape moiré. One-dimensional patterns may appear when superimposing an opaque layer containing tiny horizontal transparent lines on top of a layer containing a complex shape which is periodically repeating along the vertical axis . Moiré patterns revealing complex shapes, or sequences of symbols embedded in one of

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2528-405: Is rotated by an angle α . Seen from afar, we can also see darker and paler lines: the pale lines correspond to the lines of nodes , that is, lines passing through the intersections of the two patterns. If we consider a cell of the lattice formed, we can see that it is a rhombus with the four sides equal to d = ⁠ p / sin α ⁠ ; (we have a right triangle whose hypotenuse

2607-405: Is shifted by n δp compared to the n th line of the first network. The middle of the first dark zone thus corresponds to n ⋅ δ p = p 2 {\displaystyle n\cdot \delta p={\frac {p}{2}}} that is n = p 2 δ p . {\displaystyle n={\frac {p}{2\delta p}}.} The distance d between

2686-486: Is the average of and therefore close to k 1 and k 2 , the moiré effect is distinctively demonstrated by the sinusoidal envelope "beat" function cos( Bx ) , whose periodic variation is half the difference of the periodic variations k 1 and k 2 (and evidently much lower in frequency). Other one-dimensional moiré effects include the classic beat frequency tone which is heard when two pure notes of almost identical pitch are sounded simultaneously. This

2765-1552: Is the hypotenuse of a right triangle and the sides of the right angle are d (1 + cos α ) and p . The Pythagorean theorem gives: ( 2 D ) 2 = d 2 ( 1 + cos ⁡ α ) 2 + p 2 {\displaystyle (2D)^{2}=d^{2}(1+\cos \alpha )^{2}+p^{2}} that is: ( 2 D ) 2 = p 2 sin 2 ⁡ α ( 1 + cos ⁡ α ) 2 + p 2 = p 2 ⋅ ( ( 1 + cos ⁡ α ) 2 sin 2 ⁡ α + 1 ) {\displaystyle {\begin{aligned}(2D)^{2}&={\frac {p^{2}}{\sin ^{2}\alpha }}(1+\cos \alpha )^{2}+p^{2}\\[5pt]&=p^{2}\cdot \left({\frac {(1+\cos \alpha )^{2}}{\sin ^{2}\alpha }}+1\right)\end{aligned}}} thus ( 2 D ) 2 = 2 p 2 ⋅ 1 + cos ⁡ α sin 2 ⁡ α D = p 2 sin ⁡ α 2 . {\displaystyle {\begin{aligned}(2D)^{2}&=2p^{2}\cdot {\frac {1+\cos \alpha }{\sin ^{2}\alpha }}\\[5pt]D&={\frac {\frac {p}{2}}{\sin {\frac {\alpha }{2}}}}.\end{aligned}}} When α

2844-551: Is typically a thin layer directly in front of the sensor, and works by effectively blurring any potentially problematic details that are finer than the resolution of the sensor. The Bayer filter is almost universal on consumer digital cameras. Alternatives include the CYGM filter ( cyan , yellow , green, magenta ) and RGBE filter (red, green, blue, emerald ), which require similar demosaicing. The Foveon X3 sensor (which layers red, green, and blue sensors vertically rather than using

2923-411: Is used in shoreside beacons called "Inogon leading marks" or "Inogon lights", manufactured by Inogon Licens AB, Sweden, to designate the safest path of travel for ships heading to locks, marinas, ports, etc., or to indicate underwater hazards (such as pipelines or cables). The moiré effect creates arrows that point towards an imaginary line marking the hazard or line of safe passage; as navigators pass over

3002-531: Is very small ( α < ⁠ π / 6 ⁠ ) the following small-angle approximations can be made: sin ⁡ α ≈ α cos ⁡ α ≈ 1 {\displaystyle {\begin{aligned}\sin \alpha &\approx \alpha \\\cos \alpha &\approx 1\end{aligned}}} thus D ≈ p α . {\displaystyle D\approx {\frac {p}{\alpha }}.} We can see that

3081-407: Is what is known and seen as false coloring. Typically this artifact manifests itself along edges, where abrupt or unnatural shifts in color occur as a result of misinterpolating across, rather than along, an edge. Various methods exist for preventing and removing this false coloring. Smooth hue transition interpolation is used during the demosaicing to prevent false colors from manifesting themselves in

3160-644: The iPhone 6 's front camera released in 2014. Quad Bayer is similar to Bayer filter, however adjacent 2x2 pixels are the same color, the 4x4 pattern features 4x blue, 4x red, and 8x green. For darker scenes, signal processing can combine data from each 2x2 group, essentially like a larger pixel. For brighter scenes, signal processing can convert the Quad Bayer into a conventional Bayer filter to achieve higher resolution. The pixels in Quad Bayer can be operated in long-time integration and short-time integration to achieve single shot HDR, reducing blending issues. Quad Bayer

3239-506: The angle, the final error is proportional to the measurement error. If we choose to measure the spacing, the final error is proportional to the inverse of the spacing. Thus, for the small angles, it is best to measure the spacing. In graphic arts and prepress , the usual technology for printing full-color images involves the superimposition of halftone screens. These are regular rectangular dot patterns—often four of them, printed in cyan, yellow, magenta, and black. Some kind of moiré pattern

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3318-413: The assumption that the color of an area in the image is relatively constant even under changing light conditions, so that the color channels are highly correlated with each other. Therefore, the green channel is interpolated at first then the red and afterwards the blue channel, so that the color ratio red-green respective blue-green are constant. There are other methods that make different assumptions about

3397-442: The blue value. This simple approach works well in areas with constant color or smooth gradients, but it can cause artifacts such as color bleeding in areas where there are abrupt changes in color or brightness especially noticeable along sharp edges in the image. Because of this, other demosaicing methods attempt to identify high-contrast edges and only interpolate along these edges, but not across them. Other algorithms are based on

3476-403: The centre point of an oncoming bridge; when the vessel is aligned with the centreline, vertical lines are visible. Inogon lights are deployed at airports to help pilots on the ground keep to the centreline while docking on stand. In manufacturing industries, these patterns are used for studying microscopic strain in materials: by deforming a grid with respect to a reference grid and measuring

3555-415: The close spacing of similarly colored photosites. The Fujifilm X-Trans CMOS sensor used in many Fujifilm X-series cameras is claimed to provide better resistance to color moiré than the Bayer filter, and as such they can be made without an anti-aliasing filter. This in turn allows cameras using the sensor to achieve a higher resolution with the same megapixel count. Also, the new design is claimed to reduce

3634-438: The color value of the pixels of the same color in the neighborhood. For example, once the chip has been exposed to an image, each pixel can be read. A pixel with a green filter provides an exact measurement of the green component. The red and blue components for this pixel are obtained from the neighbors. For a green pixel, two red neighbors can be interpolated to yield the red value, also two blue pixels can be interpolated to yield

3713-408: The design is visible even at great distances. Consider two patterns made of parallel and equidistant lines, e.g., vertical lines. The step of the first pattern is p , the step of the second is p + δp , with 0 < δp < p . If the lines of the patterns are superimposed at the left of the figure, the shift between the lines increases when going to the right. After a given number of lines,

3792-457: The effect. Photographs of a TV screen taken with a digital camera often exhibit moiré patterns. Since both the TV screen and the digital camera use a scanning technique to produce or to capture pictures with horizontal scan lines, the conflicting sets of lines cause the moiré patterns. To avoid the effect, the digital camera can be aimed at an angle of 30 degrees to the TV screen. The moiré effect

3871-434: The final image. However, there are other algorithms that can remove false colors after demosaicing. These have the benefit of removing false coloring artifacts from the image while using a more robust demosaicing algorithm for interpolating the red and blue color planes. The zippering artifact is another side effect of CFA demosaicing, which also occurs primarily along edges, is known as the zipper effect. Simply put, zippering

3950-539: The green photosensors luminance-sensitive elements and the red and blue ones chrominance-sensitive elements . He used twice as many green elements as red or blue to mimic the physiology of the human eye . The luminance perception of the human retina uses M and L cone cells combined, during daylight vision, which are most sensitive to green light. These elements are referred to as sensor elements , sensels , pixel sensors , or simply pixels ; sample values sensed by them, after interpolation, become image pixels . At

4029-523: The hall from Bryce's group. They were working on psycho-physics related to user assessment of digital image quality, color perception, etc. The Bayer filter enables a digital imaging system to do what the eye does. The extra green sensors provide more luminance information, as the rods in the eye do, when it is dark. When the digital imaging system and the eye encounter situations with low levels of illumination, both systems can provide and use more luminance information and less chrominance information. Bayer

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4108-518: The image content and starting from this attempt to calculate the missing color values. Images with small-scale detail close to the resolution limit of the digital sensor can be a problem to the demosaicing algorithm, producing a result which does not look like the model. The most frequent artifact is Moiré , which may appear as repeating patterns, color artifacts or pixels arranged in an unrealistic maze-like pattern. A common and unfortunate artifact of Color Filter Array (CFA) interpolation or demosaicing

4187-457: The image. However, even with a theoretically perfect sensor that could capture and distinguish all colors at each photosite, Moiré and other artifacts could still appear. This is an unavoidable consequence of any system that samples an otherwise continuous signal at discrete intervals or locations. For this reason, most photographic digital sensors incorporate something called an optical low-pass filter (OLPF) or an anti-aliasing (AA) filter . This

4266-436: The incidence of false colors, by having red, blue and green pixels in each line. The arrangement of these pixels is also said to provide grain more like film. One of main drawbacks for custom patterns is that they may lack full support in third party raw processing software like Adobe Photoshop Lightroom where adding improvements took multiple years. Sony introduced Quad Bayer color filter array, which first featured in

4345-437: The layers (in form of periodically repeated compressed shapes) are created with shape moiré, otherwise called band moiré patterns. One of the most important properties of shape moiré is its ability to magnify tiny shapes along either one or both axes, that is, stretching. A common 2D example of moiré magnification occurs when viewing a chain-link fence through a second chain-link fence of identical design. The fine structure of

4424-482: The line, the arrows on the beacon appear to become vertical bands before changing back to arrows pointing in the reverse direction. An example can be found in the UK on the eastern shore of Southampton Water , opposite Fawley oil refinery ( 50°51′21.63″N 1°19′44.77″W  /  50.8560083°N 1.3291028°W  / 50.8560083; -1.3291028 ). Similar moiré effect beacons can be used to guide mariners to

4503-595: The middle of a pale zone and a dark zone is d = n ⋅ ( p + δ p ) = p 2 2 δ p + p 2 {\displaystyle d=n\cdot (p+\delta p)={\frac {p^{2}}{2\delta p}}+{\frac {p}{2}}} the distance between the middle of two dark zones, which is also the distance between two pale zones, is 2 d = p 2 δ p + p {\displaystyle 2d={\frac {p^{2}}{\delta p}}+p} From this formula, we can see that: The principle of

4582-489: The moiré is similar to the Vernier scale . The essence of the moiré effect is the (mainly visual) perception of a distinctly different third pattern which is caused by inexact superimposition of two similar patterns. The mathematical representation of these patterns is not trivially obtained and can seem somewhat arbitrary. In this section we shall give a mathematical example of two parallel patterns whose superimposition forms

4661-448: The moiré pattern, the stress levels and patterns can be deduced. This technique is attractive because the scale of the moiré pattern is much larger than the deflection that causes it, making measurement easier. The moiré effect can be used in strain measurement: the operator just has to draw a pattern on the object, and superimpose the reference pattern to the deformed pattern on the deformed object. A similar effect can be obtained by

4740-429: The optical patterns of lines creates a real and visible pattern of roughly parallel dark and light bands, the moiré pattern, superimposed on the lines. The moiré effect also occurs between overlapping transparent objects. For example, an invisible phase mask is made of a transparent polymer with a wavy thickness profile. As light shines through two overlaid masks of similar phase patterns, a broad moiré pattern occurs on

4819-889: The pattern's grey intensity, measured as the number of intensity cycles per unit distance. Since the sine function is cyclic over argument changes of 2π , the distance increment Δ x per intensity cycle (the wavelength) obtains when k Δ x = 2π , or Δ x = ⁠ 2π / k ⁠ . Consider now two such patterns, where one has a slightly different periodic variation from the other: f 1 = 1 + sin ⁡ ( k 1 x ) 2 f 2 = 1 + sin ⁡ ( k 2 x ) 2 {\displaystyle {\begin{aligned}f_{1}&={\frac {1+\sin(k_{1}x)}{2}}\\[4pt]f_{2}&={\frac {1+\sin(k_{2}x)}{2}}\end{aligned}}} such that k 1 ≈ k 2 . The average of these two functions, representing

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4898-417: The patterns are opposed: the lines of the second pattern are between the lines of the first pattern. If we look from a far distance, we have the feeling of pale zones when the lines are superimposed (there is white between the lines), and of dark zones when the lines are "opposed". The middle of the first dark zone is when the shift is equal to ⁠ p / 2 ⁠ . The n th line of the second pattern

4977-415: The printmaking process.) We now consider the "printing" superimposition of two almost similar, sinusoidally varying, grey-scale patterns to show how they produce a moiré effect in first printing one pattern on the paper, and then printing the other pattern over the first, keeping their coordinate axes in register. We represent the grey intensity in each pattern by a positive opacity function of distance along

5056-476: The same color, the 6x6 pattern features 9x blue, 9x red, and 18x green. Bryce Bayer Bryce Edward Bayer (/ˈbaɪər/; pronounced BYE-er, August 15, 1929 – November 13, 2012) was an American scientist who invented the Bayer filter pattern, which is used in most modern color digital cameras. He has been called "the maestro without whom photography as we know wouldn't have been the same." Bryce Edward Bayer

5135-427: The same color. The main reason for this type of array is to contribute to pixel "binning", where two adjacent photosites can be merged, making the sensor itself more "sensitive" to light. Another reason is for the sensor to record two different exposures, which is then merged to produce an image with greater dynamic range. The underlying circuitry has two read-out channels that take their information from alternate rows of

5214-417: The sensor. The result is that it can act like two interleaved sensors, with different exposure times for each half of the photosites. Half of the photosites can be intentionally underexposed so that they fully capture the brighter areas of the scene. This retained highlight information can then be blended in with the output from the other half of the sensor that is recording a 'full' exposure, again making use of

5293-442: The sensor. They present several patterns, but none with a repeating unit as small as the Bayer pattern's 2×2 unit. Another 2007 U.S. patent filing, by Edward T. Chang, claims a sensor where "the color filter has a pattern comprising 2×2 blocks of pixels composed of one red, one blue, one green and one transparent pixel," in a configuration intended to include infrared sensitivity for higher overall sensitivity. The Kodak patent filing

5372-408: The smaller α is, the farther apart the pale lines; when both patterns are parallel ( α = 0 ), the spacing between the pale lines is infinite (there is no pale line). There are thus two ways to determine α : by the orientation of the pale lines and by their spacing α ≈ p D {\displaystyle \alpha \approx {\frac {p}{D}}} If we choose to measure

5451-738: The superimposed printed image, evaluates as follows (see reverse identities here : Prosthaphaeresis ): f 3 = f 1 + f 2 2 = 1 2 + sin ⁡ ( k 1 x ) + sin ⁡ ( k 2 x ) 4 = 1 + sin ⁡ ( A x ) cos ⁡ ( B x ) 2 {\displaystyle {\begin{aligned}f_{3}&={\frac {f_{1}+f_{2}}{2}}\\[5pt]&={\frac {1}{2}}+{\frac {\sin(k_{1}x)+\sin(k_{2}x)}{4}}\\[5pt]&={\frac {1+\sin(Ax)\cos(Bx)}{2}}\end{aligned}}} where it

5530-472: The superposition of a holographic image of the object to the object itself: the hologram is the reference step, and the difference with the object are the deformations, which appear as pale and dark lines. Some image scanner computer programs provide an optional filter , called a "descreen" filter, to remove moiré pattern artifacts which would otherwise be produced when scanning printed halftone images to produce digital images. Many banknotes exploit

5609-462: The surrounding pixels of the corresponding colors to estimate the values for a particular pixel. Different algorithms requiring various amounts of computing power result in varying-quality final images. This can be done in-camera, producing a JPEG or TIFF image, or outside the camera using the raw data directly from the sensor. Since the processing power of the camera processor is limited, many photographers prefer to do these operations manually on

5688-596: The test of time." Larry Scarff, a former chairman of the Camera Phone Image Quality Standards Group, told the Times that "Ninety-nine point nine-nine percent of all digital cameras — cellphones, pocket cameras, webcams and consumer digital video cameras — use the Bayer pattern to produce color pictures." Dr. Terry Taber, Kodak Vice President and Chief Technology Officer has said that the "elegant colour technology invented by Bryce Bayer

5767-403: The time Bayer registered his patent, he also proposed to use a cyan-magenta-yellow combination, that is another set of opposite colors. This arrangement was impractical at the time because the necessary dyes did not exist, but is used in some new digital cameras. The big advantage of the new CMY dyes is that they have an improved light absorption characteristic; that is, their quantum efficiency

5846-471: Was a loan of the English mohair (attested 1610). In French usage, the noun gave rise to the verb moirer , "to produce a watered textile by weaving or pressing", by the 18th century. The adjective moiré formed from this verb is in use from at least 1823. Moiré patterns are often an artifact of images produced by various digital imaging and computer graphics techniques, for example when scanning

5925-439: Was asked by his colleague Peter Dillon to consider the best color pattern to use for an integral color image sensor being developed by Dillon. Bayer documented his ideas in his KRL lab notebook on May 24, 1974, as shown in the figure. His entry includes a color sketch of his now famous "Bayer pattern" and states that "each of the red, green and blue records are sampled in regular arrays, with twice as many points for green, which

6004-618: Was awarded the Royal Photographic Society 's Progress Medal in 2009 given "in recognition of any invention, research, publication or other contribution which has resulted in an important advance in the scientific or technological development of photography or imaging in the widest sense." In 2012, Bayer received the first Camera Origination and Imaging Medal from the Society of Motion Picture and Television Engineers. Bayer and his wife had two sons, Douglas and David , and

6083-535: Was born in Portland, Maine , on August 15, 1929, to Alton and Marguerite Willard Bayer. As a boy he tinkered with Brownies and other cameras. He graduated in 1947 from Deering High School in Portland, where he spent a good deal of time in the school darkroom. "He, in fact, processed all of the pictures for his high school yearbook," his son David told The New York Times following Bayer's death. After receiving

6162-516: Was earlier. Such cells have previously been used in " CMYW " (cyan, magenta, yellow, and white) "RGBW" (red, green, blue, white) sensors, but Kodak has not compared the new filter pattern to them yet. Fujifilm's EXR color filter array are manufactured in both CCD ( SuperCCD ) and CMOS (BSI CMOS). As with the SuperCCD, the filter itself is rotated 45 degrees. Unlike conventional Bayer filter designs, there are always two adjacent photosites detecting

6241-512: Was first used in the Kodak DCS 200 camera, which was introduced in 1992. It is used today in almost all color cameras, including those in smartphones, computers, camcorders, and drones. In the Bayer pattern, half of the pixels collect green light, and the others are evenly divided between red and blue light. The resulting Nyquist domains for the green sampling maintains the same Nyquist frequency for horizontal and vertical spatial frequencies as

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