- The CIE system provides a numerical specification for color using tristimulus values that represent the amounts of three primary colors (red, blue, and green) needed to match a particular color.
- Factors like the light source, observer, and surface properties affect the perceived color. The CIE system defines standard illuminants, observers, and viewing conditions to account for these factors.
- Tristimulus values along with the CIE system allow colors to be objectively measured and reproduced across different lighting and viewing conditions.
Do Not just learn computer graphics an close your computer tab and go away..
APPLY them in real business,
Visit Daroko blog for real IT skills applications,androind, Computer graphics,Networking,Programming,IT jobs Types, IT news and applications,blogging,Builing a website, IT companies and how you can form yours, Technology news and very many More IT related subject.
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• Daroko blog (www.professionalbloggertricks.com)
• Presentation by Daroko blog, to see More tutorials more than this one here, Daroko blog has all tutorials related with IT course, simply visit the site by simply Entering the phrase Daroko blog (www.professionalbloggertricks.com) to search engines such as Google or yahoo!, learn some Blogging, affiliate marketing ,and ways of making Money with the computer graphic Applications(it is useless to learn all these tutorials when you can apply them as a student you know),also learn where you can apply all IT skills in a real Business Environment after learning Graphics another computer realate courses.ly
• Be practically real, not just academic reader
The document discusses color science and human color perception. It explains that color depends on the wavelength of light and how the eye perceives different wavelengths. The eye contains three types of cones that are most sensitive to red, green, and blue light. Combinations of these primary colors can reproduce any color visible to humans. Common color models used in devices include RGB used in computer monitors, CMYK used in printing, and YUV/YCbCr used in video and television.
Color can be described through hue, saturation, and brightness. There are two main color models - additive RGB used in screens and subtractive CMYK used in printing. The HSV color space also describes colors through hue, saturation, and value. Precise color is specified through dominant wavelength, excitation purity, and brightness based on the electromagnetic spectrum of visible light frequencies between 400-700nm. Video color models are derived from analog TV methods and separate luminance from color. The eye sees yellow-green best and blue worst, and the CIE color space provides a three-dimensional representation of color perception.
This document discusses color image processing and provides information on various color models and color fundamentals. It describes full-color and pseudo-color processing, color fundamentals including the visible light spectrum, color perception by the human eye, and color properties. It also summarizes RGB, CMY/CMYK, and HSI color models, conversions between models, and methods for pseudo-color image processing including intensity slicing and intensity to color transformations.
This document discusses color models and color spaces. It defines color models as specifications for representing colors as points within a coordinate system. Common color models include RGB, grayscale, and binary. It describes how human vision perceives color through red, green, and blue cone receptors in the eye. Hue, saturation, and brightness are also defined as the three properties that describe color, with hue being the actual color, saturation being the purity of the color, and brightness being the relative intensity.
This document discusses various color models used in computer graphics including RGB, HSV, HSL, CMY, and CMYK. It explains the key components of each model such as hue, saturation, value, and how colors are represented. Common applications of different color models are also summarized such as RGB for computer displays and CMYK for printing. In addition, the concepts of dithering and half-toning techniques used to reproduce colors on devices are introduced.
The document discusses the chromaticity diagram, which is a plot of y versus x chromaticity coordinates that represents all possible colors. It can be used to determine properties of colors like dominant wavelength, excitation purity, and whether they will appear neutral, saturated, or as shades of spectrum colors. However, the chromaticity diagram is two-dimensional and does not fully represent color, with the third dimension usually taken to be the Y tristimulus value, which indicates lightness.
Do Not just learn computer graphics an close your computer tab and go away..
APPLY them in real business,
Visit Daroko blog for real IT skills applications,androind, Computer graphics,Networking,Programming,IT jobs Types, IT news and applications,blogging,Builing a website, IT companies and how you can form yours, Technology news and very many More IT related subject.
-simply google:Daroko blog(professionalbloggertricks.com)
• Daroko blog (www.professionalbloggertricks.com)
• Presentation by Daroko blog, to see More tutorials more than this one here, Daroko blog has all tutorials related with IT course, simply visit the site by simply Entering the phrase Daroko blog (www.professionalbloggertricks.com) to search engines such as Google or yahoo!, learn some Blogging, affiliate marketing ,and ways of making Money with the computer graphic Applications(it is useless to learn all these tutorials when you can apply them as a student you know),also learn where you can apply all IT skills in a real Business Environment after learning Graphics another computer realate courses.ly
• Be practically real, not just academic reader
The document discusses color science and human color perception. It explains that color depends on the wavelength of light and how the eye perceives different wavelengths. The eye contains three types of cones that are most sensitive to red, green, and blue light. Combinations of these primary colors can reproduce any color visible to humans. Common color models used in devices include RGB used in computer monitors, CMYK used in printing, and YUV/YCbCr used in video and television.
Color can be described through hue, saturation, and brightness. There are two main color models - additive RGB used in screens and subtractive CMYK used in printing. The HSV color space also describes colors through hue, saturation, and value. Precise color is specified through dominant wavelength, excitation purity, and brightness based on the electromagnetic spectrum of visible light frequencies between 400-700nm. Video color models are derived from analog TV methods and separate luminance from color. The eye sees yellow-green best and blue worst, and the CIE color space provides a three-dimensional representation of color perception.
This document discusses color image processing and provides information on various color models and color fundamentals. It describes full-color and pseudo-color processing, color fundamentals including the visible light spectrum, color perception by the human eye, and color properties. It also summarizes RGB, CMY/CMYK, and HSI color models, conversions between models, and methods for pseudo-color image processing including intensity slicing and intensity to color transformations.
This document discusses color models and color spaces. It defines color models as specifications for representing colors as points within a coordinate system. Common color models include RGB, grayscale, and binary. It describes how human vision perceives color through red, green, and blue cone receptors in the eye. Hue, saturation, and brightness are also defined as the three properties that describe color, with hue being the actual color, saturation being the purity of the color, and brightness being the relative intensity.
This document discusses various color models used in computer graphics including RGB, HSV, HSL, CMY, and CMYK. It explains the key components of each model such as hue, saturation, value, and how colors are represented. Common applications of different color models are also summarized such as RGB for computer displays and CMYK for printing. In addition, the concepts of dithering and half-toning techniques used to reproduce colors on devices are introduced.
The document discusses the chromaticity diagram, which is a plot of y versus x chromaticity coordinates that represents all possible colors. It can be used to determine properties of colors like dominant wavelength, excitation purity, and whether they will appear neutral, saturated, or as shades of spectrum colors. However, the chromaticity diagram is two-dimensional and does not fully represent color, with the third dimension usually taken to be the Y tristimulus value, which indicates lightness.
This document contains information about a lecture on digital image processing given by Dr. Moe Moe Myint at Technological University in Kyaukse, Myanmar. It provides the lecture schedule and contact information for Dr. Myint, as well as an outline of topics to be covered in Chapter 6, including color fundamentals, color models, color transformations, smoothing and sharpening of color images, and color image compression. The document discusses concepts such as the RGB, CMYK, and HSI color models and how they represent color, as well as methods for processing and manipulating colors in digital images.
Any colour that can be specified using a model will correspond to a single point within the subspace it defines. Each colour model is oriented towards either specific hardware (RGB,CMY,YIQ), or image processing applications (HSI).
This document discusses color image processing and provides details on color fundamentals, color models, and pseudocolor image processing techniques. It introduces color image processing, full-color versus pseudocolor processing, and several color models including RGB, CMY, and HSI. Pseudocolor processing techniques of intensity slicing and gray level to color transformation are explained, where grayscale values in an image are assigned colors based on intensity ranges or grayscale levels.
In imaging science, image processing is processing of images using mathematical operations by using any form of signal processing for which the input is an image, a series of images, or a video, such as a photograph or video frame; the output of image processing may be either an image or a set of characteristics or parameters related to the image. Most image-processing techniques involve treating the image as a two-dimensional signal and applying standard signal-processing techniques to it. Images are also processed as three-dimensional signals where the third-dimension being time or the z-axis.
Image processing usually refers to digital image processing, but optical and analog image processing also are possible. This article is about general techniques that apply to all of them. The acquisition of images (producing the input image in the first place) is referred to as imaging.
Closely related to image processing are computer graphics and computer vision. In computer graphics, images are manually made from physical models of objects, environments, and lighting, instead of being acquired (via imaging devices such as cameras) from natural scenes, as in most animated movies. Computer vision, on the other hand, is often considered high-level image processing out of which a machine/computer/software intends to decipher the physical contents of an image or a sequence of images (e.g., videos or 3D full-body magnetic resonance scans).
In modern sciences and technologies, images also gain much broader scopes due to the ever growing importance of scientific visualization (of often large-scale complex scientific/experimental data). Examples include microarray data in genetic research, or real-time multi-asset portfolio trading in finance.
color image processing is divided into two major areas:
1. Full Color image Processing
2. Pseudo Color image Processing
It Includes Color Fundamentals,Color Models,Pseudo color image Processing,Full Color image Processing,Color Transformation.
full color,pseudo color,color fundamentals,Hue saturation Brightness,color model,RGB color model,CMY and CMYK color model,HSI color model,Coverting RGB to HSI, HSI examples
- The document discusses colour measurement and the CIE 1931 chromaticity diagram. It explains how colour is defined using tristimulus values and chromaticity coordinates that locate colours on the diagram.
- An experiment measures the chromaticity coordinates and tristimulus values of primary red, green, and blue light sources, both individually and combined. The results are plotted on the chromaticity diagram to analyze colour mixing and purity.
- The experiment finds the red source is a pure spectral colour since its coordinates fall on the spectral locus. The green and blue sources have high but not total purity since their coordinates are close to but not on the spectral locus.
Compututer Graphics - Color Modeling And RenderingPrince Soni
This document discusses various color models and rendering techniques. It describes additive and subtractive color models, including the RGB, CMY, and HSV color models. It also discusses illumination models, including ambient light, diffuse reflection, and specular reflection. Common rendering techniques like Gouraud shading and Phong shading are summarized, which interpolate lighting across triangle surfaces. Ray tracing is also briefly explained as a technique for simulating light paths.
The document discusses the CIE standard colorimetric system. It explains that the CIE had to define standard primaries, light sources, and a standard observer to establish a uniform color specification system. It describes how the CIE chose the primary colors, standard illuminants A, B, and C, viewing geometry, and normalized the tristimulus values between 0-100 to establish a unified color space. The CIE system separates the properties of a color sample from the light source to account for differences in intensity and spectrum.
The HSI (hue, saturation, intensity) color model represents color in a way that is more perceptually relevant to humans compared to the RGB (red, green, blue) model. Hue represents the color (such as red, yellow, blue), saturation represents the amount of gray, and intensity represents the brightness. The HSI model separates intensity from color information. Converting an image to HSI allows color manipulations like changing hue or saturation before converting back to RGB for display.
This document discusses color image processing and various color models. It begins with an overview of color fundamentals, including the visible light spectrum and primary/secondary colors. It then describes several color models - RGB, CMY, and HSI. Conversion between these color spaces is also covered. The document also discusses pseudocolor image processing techniques like intensity slicing and gray level to color transformations. Finally, it covers full-color image processing, including treating each color component separately, color complements, and color image smoothing and segmentation in RGB space.
This document discusses color image processing and different color models. It begins with an introduction and then covers color fundamentals such as brightness, hue, and saturation. It describes common color models like RGB, CMY, HSI, and YIQ. Pseudo color processing and full color image processing are explained. Color transformations between color models are also discussed. Implementation tips for interpolation methods in color processing are provided. The document concludes with thanks to the head of the computer science department.
3.13 usefulness and limitation of the cie systemQC Labs
The CIE system of color specification has been successful and widely used over 60 years, providing a standardized way to measure and describe colors based on tristimulus values. However, it has limitations as it ignores other visual attributes like texture and gloss, and a color match is only guaranteed under the standard observer, illuminant, and viewing conditions used to measure the original sample. The CIE system provides a limited but useful description of color if the measurement conditions are carefully controlled and considered.
Color is a sensation produced by the human visual system. The two most common color models are RGB, used for computer displays, and CMYK, used for printing. RGB is an additive model that uses combinations of red, green, and blue light to produce colors. CMYK is a subtractive model that uses combinations of cyan, magenta, yellow, and black inks to produce colors. Both models represent colors using three numeric values corresponding to the intensities of the primary colors.
1. The document discusses various color models including RGB, CMY(K), HSV, HSL, and YIQ color models.
2. It describes the key components and properties of each color model such as hue, saturation, brightness. For example, RGB is an additive color model where primary colors are combined with light, while CMY(K) is a subtractive model used in printing.
3. Different color models have different applications based on their properties. For example, RGB is used for computer graphics and image processing while CMY(K) is used for printing and YIQ is used for television broadcasting.
Color fundamentals and color models - Digital Image ProcessingAmna
This presentation is based on Color fundamentals and Color models.
~ Introduction to Colors
~ Color in Image Processing
~ Color Fundamentals
~ Color Models
~ RGB Model
~ CMY Model
~ CMYK Model
~ HSI Model
~ HSI and RGB
~ RGB To HSI
~ HSI To RGB
Interactive Volumetric Lighting Simulating Scattering and ShadowingMarc Sunet
This document describes an interactive volumetric lighting model that simulates scattering and hard shadows. It presents a lighting model based on emission, attenuation, and scattering. Light is propagated through the volume using a two-pass algorithm to compute incoming and outgoing light. Rendering applies the lighting model and uses a transfer function. A user study found the model provided better depth perception than Phong lighting. Future work includes integrating light sources and evaluating the model.
This document discusses color image processing and color models. It covers:
1) The basics of color perception and how humans see color through cone cells in the eye sensitive to different wavelengths.
2) Common color models like RGB, HSV, and CMYK and how they represent color.
3) Converting between color models and adjusting color properties like hue, saturation, and intensity.
4) Applications of color processing like pseudocoloring grayscale images and correcting color imbalances.
5) Approaches for adapting color images to be more visible for those with color vision deficiencies.
This document provides an overview of light, color, and human color perception. It discusses that color is a psychological property resulting from light interacting with our visual system. The physics of light is described in terms of wavelength. Human color vision involves three types of cones that differ in photopigment sensitivity. Color can be represented using models like RGB, CIE XYZ, and HSV. Computer vision applications make use of color through techniques like color histograms, skin detection, and image segmentation.
This document provides an overview of lighting design fundamentals and applications. It discusses basic light concepts including photometric quantities used to measure light, illumination quality, and different types of lamps such as incandescent, fluorescent, and high intensity discharge lamps. It also covers topics such as quantity and quality of light, lighting control systems, and current lighting equipment and practices.
This document contains information about a lecture on digital image processing given by Dr. Moe Moe Myint at Technological University in Kyaukse, Myanmar. It provides the lecture schedule and contact information for Dr. Myint, as well as an outline of topics to be covered in Chapter 6, including color fundamentals, color models, color transformations, smoothing and sharpening of color images, and color image compression. The document discusses concepts such as the RGB, CMYK, and HSI color models and how they represent color, as well as methods for processing and manipulating colors in digital images.
Any colour that can be specified using a model will correspond to a single point within the subspace it defines. Each colour model is oriented towards either specific hardware (RGB,CMY,YIQ), or image processing applications (HSI).
This document discusses color image processing and provides details on color fundamentals, color models, and pseudocolor image processing techniques. It introduces color image processing, full-color versus pseudocolor processing, and several color models including RGB, CMY, and HSI. Pseudocolor processing techniques of intensity slicing and gray level to color transformation are explained, where grayscale values in an image are assigned colors based on intensity ranges or grayscale levels.
In imaging science, image processing is processing of images using mathematical operations by using any form of signal processing for which the input is an image, a series of images, or a video, such as a photograph or video frame; the output of image processing may be either an image or a set of characteristics or parameters related to the image. Most image-processing techniques involve treating the image as a two-dimensional signal and applying standard signal-processing techniques to it. Images are also processed as three-dimensional signals where the third-dimension being time or the z-axis.
Image processing usually refers to digital image processing, but optical and analog image processing also are possible. This article is about general techniques that apply to all of them. The acquisition of images (producing the input image in the first place) is referred to as imaging.
Closely related to image processing are computer graphics and computer vision. In computer graphics, images are manually made from physical models of objects, environments, and lighting, instead of being acquired (via imaging devices such as cameras) from natural scenes, as in most animated movies. Computer vision, on the other hand, is often considered high-level image processing out of which a machine/computer/software intends to decipher the physical contents of an image or a sequence of images (e.g., videos or 3D full-body magnetic resonance scans).
In modern sciences and technologies, images also gain much broader scopes due to the ever growing importance of scientific visualization (of often large-scale complex scientific/experimental data). Examples include microarray data in genetic research, or real-time multi-asset portfolio trading in finance.
color image processing is divided into two major areas:
1. Full Color image Processing
2. Pseudo Color image Processing
It Includes Color Fundamentals,Color Models,Pseudo color image Processing,Full Color image Processing,Color Transformation.
full color,pseudo color,color fundamentals,Hue saturation Brightness,color model,RGB color model,CMY and CMYK color model,HSI color model,Coverting RGB to HSI, HSI examples
- The document discusses colour measurement and the CIE 1931 chromaticity diagram. It explains how colour is defined using tristimulus values and chromaticity coordinates that locate colours on the diagram.
- An experiment measures the chromaticity coordinates and tristimulus values of primary red, green, and blue light sources, both individually and combined. The results are plotted on the chromaticity diagram to analyze colour mixing and purity.
- The experiment finds the red source is a pure spectral colour since its coordinates fall on the spectral locus. The green and blue sources have high but not total purity since their coordinates are close to but not on the spectral locus.
Compututer Graphics - Color Modeling And RenderingPrince Soni
This document discusses various color models and rendering techniques. It describes additive and subtractive color models, including the RGB, CMY, and HSV color models. It also discusses illumination models, including ambient light, diffuse reflection, and specular reflection. Common rendering techniques like Gouraud shading and Phong shading are summarized, which interpolate lighting across triangle surfaces. Ray tracing is also briefly explained as a technique for simulating light paths.
The document discusses the CIE standard colorimetric system. It explains that the CIE had to define standard primaries, light sources, and a standard observer to establish a uniform color specification system. It describes how the CIE chose the primary colors, standard illuminants A, B, and C, viewing geometry, and normalized the tristimulus values between 0-100 to establish a unified color space. The CIE system separates the properties of a color sample from the light source to account for differences in intensity and spectrum.
The HSI (hue, saturation, intensity) color model represents color in a way that is more perceptually relevant to humans compared to the RGB (red, green, blue) model. Hue represents the color (such as red, yellow, blue), saturation represents the amount of gray, and intensity represents the brightness. The HSI model separates intensity from color information. Converting an image to HSI allows color manipulations like changing hue or saturation before converting back to RGB for display.
This document discusses color image processing and various color models. It begins with an overview of color fundamentals, including the visible light spectrum and primary/secondary colors. It then describes several color models - RGB, CMY, and HSI. Conversion between these color spaces is also covered. The document also discusses pseudocolor image processing techniques like intensity slicing and gray level to color transformations. Finally, it covers full-color image processing, including treating each color component separately, color complements, and color image smoothing and segmentation in RGB space.
This document discusses color image processing and different color models. It begins with an introduction and then covers color fundamentals such as brightness, hue, and saturation. It describes common color models like RGB, CMY, HSI, and YIQ. Pseudo color processing and full color image processing are explained. Color transformations between color models are also discussed. Implementation tips for interpolation methods in color processing are provided. The document concludes with thanks to the head of the computer science department.
3.13 usefulness and limitation of the cie systemQC Labs
The CIE system of color specification has been successful and widely used over 60 years, providing a standardized way to measure and describe colors based on tristimulus values. However, it has limitations as it ignores other visual attributes like texture and gloss, and a color match is only guaranteed under the standard observer, illuminant, and viewing conditions used to measure the original sample. The CIE system provides a limited but useful description of color if the measurement conditions are carefully controlled and considered.
Color is a sensation produced by the human visual system. The two most common color models are RGB, used for computer displays, and CMYK, used for printing. RGB is an additive model that uses combinations of red, green, and blue light to produce colors. CMYK is a subtractive model that uses combinations of cyan, magenta, yellow, and black inks to produce colors. Both models represent colors using three numeric values corresponding to the intensities of the primary colors.
1. The document discusses various color models including RGB, CMY(K), HSV, HSL, and YIQ color models.
2. It describes the key components and properties of each color model such as hue, saturation, brightness. For example, RGB is an additive color model where primary colors are combined with light, while CMY(K) is a subtractive model used in printing.
3. Different color models have different applications based on their properties. For example, RGB is used for computer graphics and image processing while CMY(K) is used for printing and YIQ is used for television broadcasting.
Color fundamentals and color models - Digital Image ProcessingAmna
This presentation is based on Color fundamentals and Color models.
~ Introduction to Colors
~ Color in Image Processing
~ Color Fundamentals
~ Color Models
~ RGB Model
~ CMY Model
~ CMYK Model
~ HSI Model
~ HSI and RGB
~ RGB To HSI
~ HSI To RGB
Interactive Volumetric Lighting Simulating Scattering and ShadowingMarc Sunet
This document describes an interactive volumetric lighting model that simulates scattering and hard shadows. It presents a lighting model based on emission, attenuation, and scattering. Light is propagated through the volume using a two-pass algorithm to compute incoming and outgoing light. Rendering applies the lighting model and uses a transfer function. A user study found the model provided better depth perception than Phong lighting. Future work includes integrating light sources and evaluating the model.
This document discusses color image processing and color models. It covers:
1) The basics of color perception and how humans see color through cone cells in the eye sensitive to different wavelengths.
2) Common color models like RGB, HSV, and CMYK and how they represent color.
3) Converting between color models and adjusting color properties like hue, saturation, and intensity.
4) Applications of color processing like pseudocoloring grayscale images and correcting color imbalances.
5) Approaches for adapting color images to be more visible for those with color vision deficiencies.
This document provides an overview of light, color, and human color perception. It discusses that color is a psychological property resulting from light interacting with our visual system. The physics of light is described in terms of wavelength. Human color vision involves three types of cones that differ in photopigment sensitivity. Color can be represented using models like RGB, CIE XYZ, and HSV. Computer vision applications make use of color through techniques like color histograms, skin detection, and image segmentation.
This document provides an overview of lighting design fundamentals and applications. It discusses basic light concepts including photometric quantities used to measure light, illumination quality, and different types of lamps such as incandescent, fluorescent, and high intensity discharge lamps. It also covers topics such as quantity and quality of light, lighting control systems, and current lighting equipment and practices.
This document provides an overview of lighting design fundamentals and applications. It discusses basic light concepts like photometric quantities used to measure light, illumination quality, and different types of lamps like incandescent, fluorescent, and high intensity discharge lamps. It also covers topics like quantity and quality of light, lighting control systems, color, color rendering, and color temperature. The document is intended to educate about key lighting design topics and current lighting technologies and practices.
This document discusses chromaticity indices and colorimetry for measuring meat color. It provides information on:
- The physiology of human color perception and the three color cones in the eye.
- Tristimulus colorimetry and the CIE LAB color space system used for objectively specifying color.
- The three properties of color - hue, saturation (chroma), and brightness (lightness).
- Formulas for calculating color difference values and interpreting them.
- Factors that affect color measurement of meat samples like sample preparation, instrument settings, and applications of the data.
This document provides a summary of a lecture on color and color perception. It begins with announcements about homework assignments. It then outlines the topics to be covered, including a recap of color and human color perception, retinal color space, color matching, linear color spaces, chromaticity, color calibration, non-linear color spaces, and notes on color reproduction. It provides context on the origins of some slides and then dives into detailed explanations and examples of these color-related topics. Key points covered include how color is a human perception of light wavelengths, the role of illuminant spectra and object reflectance, retinal vs perceived color, color matching experiments, linear color representations in different color spaces like LMS, RGB, XYZ, gam
This document discusses shade selection and color science in ceramics. It covers topics such as color perception, color measurement systems, translucency in ceramics, and shade matching guidelines. The key aspects are:
1) Color is the perception of light reflected from an object, determined by light source, observer, and the object.
2) Shade selection involves visual matching using shade guides or digital methods. Common shade guides include VITA Classical and 3D Master, which arrange shades by hue or value.
3) Factors like translucency, opalescence, and counter opalescence affect natural tooth color and are difficult to replicate precisely. Proper lighting conditions are important for accurate shade
colorimetry spectrophotometry by dr.Tasnimdr Tasnim
This document discusses colorimetry and spectrophotometry. It provides details on:
1. The principles of photometry and how it is applied to techniques like colorimetry, spectrophotometry, and turbidometry.
2. The basic components and operation of colorimeters, including light sources, monochromators/filters, sample holders, detectors, and readouts.
3. The principles of colorimetry, including Beer's law, Lambert's law, and how absorbance is measured.
4. Applications of colorimetry for estimating biochemical compounds.
5. The additional components and capabilities of spectrophotometers compared to colorimeters, allowing for more accurate analysis.
The document discusses color image processing and color models. It describes how color is perceived by the human visual system through rods and cones in the retina. Various color models are examined, including RGB, CMY, HSV, YIQ, and YUV. Color models transform between different representations of color, such as representing a color by its hue, saturation, and intensity rather than red, green, and blue values.
This document discusses color theory and different aspects of color. It defines color as the property of objects to produce different sensations in the eye based on how they reflect or emit light. It then discusses three main categories of color theory: the color wheel, color harmony, and how colors are used contextually. The color wheel shows primary, secondary, and tertiary colors and demonstrates color temperature. Warm colors like red, orange, and yellow appear closer, while cool colors like green, blue, and purple appear farther. Color values are made by adding black or white to a color. Color schemes organize colors in different ways. The document also compares CMYK and RGB color models used in printing versus screens.
The document discusses color models and color image processing. It covers the fundamentals of color, visible light spectrum, color characterization in terms of brightness, hue and saturation. Common color models like RGB, CMYK, YCbCr, HSV and HSI are described. The document also discusses color sensors in human eyes, primary and secondary colors, pseudocolor image processing techniques like intensity slicing and intensity to color transformation.
Being Prosthodontists, we deal with restorative dentistry. Restorative dentistry is a blend of science and art. Aesthetics which is one of the main concerns in restorative dentistry depends totally upon the proper shade matching of prosthesis with surrounding structures, which can be teeth or soft tissues.
Color matching is done, for better compliance.
Perception of color is a physiological response by human eyes and sensory structures of the brain towards the light reflected from an object.
This document discusses the principles of colorimetry, specifically Beer's Law and Lambert's Law. It describes how colorimetry can be used to quantitatively estimate the concentration of a colored substance or solution. The amount of light absorbed by a solution is directly proportional to its concentration and path length. This relationship can be expressed by the formula A=ɛ x C x L, where A is absorbance, ɛ is the molar extinction coefficient, C is concentration, and L is path length. The document also provides details on the hardware components of a colorimeter and describes procedures to generate a calibration curve and use it to determine the concentration of an unknown sample.
The document discusses color vision and color science. It explains that color is caused by the brain's response to light of different wavelengths. It describes how color can be measured and specified numerically using models like RGB and CIE XYZ in order to accurately reproduce and match colors. It discusses experiments showing that most people perceive color through three primary colors (the principle of trichromacy) and how linear and non-linear color spaces like HSV aim to model human color perception.
The document discusses colorimetry and spectrophotometry. Colorimetry uses photometric principles to measure the intensity of light absorbed or transmitted by colored compounds. It relies on Beer's Law, which states that absorbance is directly proportional to concentration. Spectrophotometry uses a monochromator to isolate specific wavelengths from a light source and measure absorption across the electromagnetic spectrum. It provides more accurate measurements than colorimetry due to its ability to select narrow bandwidths of light and minimize stray light. Both techniques are used to determine concentrations of analytes in solutions.
Kleuraspecten van LED toestellen - KAHO / Laboratorium voor LichttechnologieeasyFairs_belgium
This document summarizes the work of the Light & Lighting Laboratory at KU Leuven. It discusses the laboratory's research topics including LEDs, OLEDs, lighting measurements, and colorimetry. It provides an overview of the laboratory's measurement facilities and activities like industrial consultancy and PhD research. Key aspects of colorimetry are defined, including color classification, color matching, chromaticity diagrams, correlated color temperature, and color rendering. The document also examines colorimetry considerations for LEDs and how junction temperature, viewing angle, and operating time can impact color properties. Optimizing color rendering for LED clusters is also addressed.
Color is a psychological property resulting from the interaction between physical light and our visual system. The human eye contains photoreceptor cells (rods and cones) that are sensitive to different wavelengths of light and allow us to perceive color. Color matching experiments showed that any color can be matched using just three primary colors, forming the basis of trichromatic color theory. Various color spaces like RGB and CIE XYZ were developed to provide standardized ways to represent color using three values. The human visual system also exhibits color constancy, allowing us to perceive the intrinsic color of objects despite changes in lighting conditions.
There are three major classes of color measuring instruments used in the textile industry: colourimeters, 0/45° and 45/0° geometry spectrophotometers, and integrating sphere geometry spectrophotometers. Colourimeters were early pioneers but have limitations as they cannot separate pure color from appearance or detect color changes under different light sources. Reflectance spectrophotometers measure the amount of light reflected at different wavelengths to produce a reflectance spectrum, which can be used to calculate CIE XYZ values. They illuminate samples with white light and calculate reflected light levels at 31 wavelength intervals using a monochromating device. Main components are a light source, optical system, light dispersing system, detector, and
Open Graphics Library (OpenGL)[3][4] is a cross-language, cross-platform application programming interface (API) for rendering 2D and 3D vector graphics. The API is typically used to interact with a graphics processing unit (GPU), to achieve hardware-accelerated rendering.
Silicon Graphics Inc., (SGI) started developing OpenGL in 1991 and released it in January 1992;[5] applications use it extensively in the fields of computer-aided design (CAD), virtual reality, scientific visualization, information visualization, flight simulation, and video games. OpenGL is managed by the non-profit technology consortium Khronos Group.
The CIE system of color specification established in 1931 has remained largely unchanged, but some additions have been made over time, including:
- Defining standard illuminants D and supplementary standard observer based on 10-degree field of view in 1964.
- Recommending reference standards for measuring reflectance factors.
- Specifying measurement geometries such as 45/0 and 0/45 viewing configurations.
This document discusses color theory and spectrophotometry. It provides definitions for key color science terms like color, hue, fluorescence, and luminescence. It describes the basic components and functions of spectrophotometers, which are used to objectively measure color. Spectrophotometers analyze the spectral composition and wavelength of light to determine color properties. The document also outlines several color spaces like CIE 1931, L*a*b*, and L*C*h that are used to numerically define and compare colors in an objective, standardized way.
How to Prepare for Interview, Prepare Covering Letter and Resume. What are the important questions not to miss during an Interview?
People fail in interview not because that they not eligible but because that they didn't present their skills and qualities efficiently
E-textiles has electronic components in it.
Nano coatings are one type of Fabric Technology of Smart Clothes.
The answer is b) Thermoplastic polyurethane (TPU).
The document discusses how to create patterns for a classic top and close-fitting one-piece dress from basic sloper patterns. For the classic top pattern, it describes shaping the waist with 1 cm darts curving inward at the center front and center back. For the close-fitting dress, it instructs to trace the close-fitting block up to the hip line, add classic waist shaping, square the length from the waist, and extend the darts.
The document discusses different types of lines used in drawing, including straight lines, angled lines, and curved lines. It also covers techniques for shading such as using graphite pencils of varying hardness and blending to create values and form. Specific methods are presented for hatching, a technique using sets of lines to represent values, and perspective, which makes objects appear smaller as they recede into the distance.
The document outlines the new product development (NPD) process. It discusses the key driving forces behind NPD including aligning with consumer needs and technological advances. The NPD process involves 8 stages: idea generation, idea screening, concept development and testing, marketing strategy development, business analysis, product development, test marketing, and commercialization. Each stage is described in 1-2 sentences. The document also notes reasons for new product failures can include overestimating demand, design flaws, poor positioning or promotion, and competitive responses.
This document discusses team building and the characteristics of effective teams. It defines a team as a highly communicative group of people with diverse backgrounds and skills working toward a shared mission. Key differences between teams and work groups are described, with teams noted as being participative, encouraging risk-taking and competition externally rather than internally. Benefits of team building include increased motivation, productivity and satisfaction. Synergy within teams requires interdependence over individuality. Conflict management is important for teams to identify and resolve problems constructively.
This document outlines the steps to open a fashion boutique business, including deciding on the boutique type, evaluating competition, conducting market research, developing a business plan, selecting a site location, obtaining legal requirements, acquiring investment capital, designing and furnishing the boutique space, identifying suppliers, handling human resources like recruiting and training staff, and managing advertising for the new boutique business. The overall process involves 11 key steps that must be completed to successfully launch and operate a fashion boutique.
This document provides styling tips for different body shapes. It identifies 5 common body shapes - pear, wedge, rectangle, apple, and hourglass. For each shape, it lists celebrity examples, key assets to emphasize, and specific dos and don'ts for styling. Examples of dos include fitted dresses, belts at the waist, and skinny jeans for an hourglass shape. Don'ts include boat neck tops and full skirts for a wedge shape. The document aims to help readers learn how to dress their unique figure type.
The document describes color ordering systems, focusing on the Munsell Color Notation system. It discusses that Munsell uses three dimensions - hue, value (lightness), and chroma (intensity) - to specify colors. Hues are arranged around a circle from red to purple to blue and so on. Value ranges from black to white. Chroma indicates how much gray is in a color, with higher numbers meaning more intense, pure colors. The document provides details on how Munsell is structured, examples of color notation, and comparisons to other systems like Natural Color System.
This document discusses color interaction with the human eye. It explains that color is a perceptual response to light entering the eye. The eye contains photoreceptors called cones that are sensitive to different wavelengths of light, including long (L), medium (M), and short (S) wavelengths. The cones detect light and send signals to the brain where color perception occurs. Spatial vision and color contrast also impact color perception, as the context of a color stimulus affects its appearance.
The document discusses the principles of design, which are rules that govern the arrangement of design elements for an intended purpose. It describes the principles of proportion, balance, rhythm, emphasis, and harmony. Proportion refers to the size relationship between parts and the whole. Balance creates a sense of equilibrium through symmetrical or asymmetrical placement of design elements. Rhythm creates a feeling of movement through repetition, gradation, radiation, opposition, or transition of elements. Emphasis draws the eye to a focal point, while harmony achieves a perfect balance of variety and unity within a design. The principles are applied to analyze and improve clothing designs.
This document discusses elements of design related to shape, form, and texture. It defines shape and silhouette, and identifies four basic garment shapes - natural, tubular, bell, and full. Form is described as having two meanings - the 3D volume or structure of clothing, and the human body itself. Texture is defined as the visual or tactile feel of a surface, and is determined by factors like fiber, yarn, construction and finish. Pattern is discussed as stripes, plaids and other motifs that can vary in size, color, and spacing. The document concludes with suggestions for a portfolio assignment involving analyzing and illustrating textures, shapes, forms and how they relate to different body types.
This document discusses the element of line in design. It defines line and describes the different types of lines including straight, curved, diagonal, and zigzag lines. It explains that lines can be either structural, which are necessary for construction of a garment, or decorative. The document also explores how different line placements and types can create various visual effects and illusions, as well as convey different meanings and moods such as masculinity, femininity, movement, and calmness. It encourages preparing a design portfolio analyzing line placements and their effects.
This document discusses elements and principles of design, focusing on color as an element of design. It defines primary, secondary, and tertiary colors, and describes color schemes including monochromatic, analogous, complementary, split-complementary, triadic, tetradic, and square. Examples of a color wheel are provided to demonstrate color relationships. Quizzes are included to test understanding of elements of design, types of design, primary colors, and tertiary colors.
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Answers are given for all the puzzles and problems.)
With Metta,
Bro. Oh Teik Bin 🙏🤓🤔🥰
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Philippine Edukasyong Pantahanan at Pangkabuhayan (EPP) CurriculumMJDuyan
(𝐓𝐋𝐄 𝟏𝟎𝟎) (𝐋𝐞𝐬𝐬𝐨𝐧 𝟏)-𝐏𝐫𝐞𝐥𝐢𝐦𝐬
𝐃𝐢𝐬𝐜𝐮𝐬𝐬 𝐭𝐡𝐞 𝐄𝐏𝐏 𝐂𝐮𝐫𝐫𝐢𝐜𝐮𝐥𝐮𝐦 𝐢𝐧 𝐭𝐡𝐞 𝐏𝐡𝐢𝐥𝐢𝐩𝐩𝐢𝐧𝐞𝐬:
- Understand the goals and objectives of the Edukasyong Pantahanan at Pangkabuhayan (EPP) curriculum, recognizing its importance in fostering practical life skills and values among students. Students will also be able to identify the key components and subjects covered, such as agriculture, home economics, industrial arts, and information and communication technology.
𝐄𝐱𝐩𝐥𝐚𝐢𝐧 𝐭𝐡𝐞 𝐍𝐚𝐭𝐮𝐫𝐞 𝐚𝐧𝐝 𝐒𝐜𝐨𝐩𝐞 𝐨𝐟 𝐚𝐧 𝐄𝐧𝐭𝐫𝐞𝐩𝐫𝐞𝐧𝐞𝐮𝐫:
-Define entrepreneurship, distinguishing it from general business activities by emphasizing its focus on innovation, risk-taking, and value creation. Students will describe the characteristics and traits of successful entrepreneurs, including their roles and responsibilities, and discuss the broader economic and social impacts of entrepreneurial activities on both local and global scales.
2. Nautre of Color Measurement
• Subjective Phenomenon : Difficult to measure
(Color, Taste and Smell)
• Objective Phenomenon: Easy to measure.
(Mass, Length, Width)
3. CIE System
• French title of the international committee
• Commission Internationale de l¢Eclairage
• The system was set up in 1931
• The CIE system tell us
– how a colour might be reproduced (by a mixture of three
primary light sources)
• The amounts of the three primaries required to match
a particular colour provide a numerical specification of
that colour.
• 546.1nm is Green Color.
4. Factors that affect color
• Light source used to illuminate its surface
• Particular observer who views it.
• Properties of the surface.
• The nature of the surface is the most
important factor.
• Color is 3D (Hue, Chroma and Value)
5. Additive and Subtractive Mixing
• Red + Blue = Purple
• Red + Yellow = Orange
• Yellow + Blue = Green
• Red + Yellow + Blue in the correct proportions
= Grey or Black.
6. Additive Mixing
• Consider red and green lights shone onto a
white screen.
• The mixture of Red plus Green in the same
appropriate proportions will reach our eye.
• The colour seen is Yellow
• Red Wavelength + Green Wavelength is what
we see and hence we call it as additive mixing.
• Multiple colors are produced by mixing R,B
and G primaries.
7. CIE System of Color Specifications
• Tristimulus Value: The amount of R,B and G
Primaries that are required to match any color
is called tristimulus value. (If RBG are
primaries)
• Any colors could be used as primary but
Primary colors must not be possible to match
by using a mixture of two other.
• Tristimulus values can be positive or negative.
• Negative values should be avoided.
8. CIE System of Color Specifications
• There is no 3 perfect primaries which could
produce all other colors, by a positive
tristimulus value. (No set of real primaries can
elimintate negative tristimulus value)
• In the CIE system, imaginary primaries are
indeed used so as to avoid negative values.
9. CIE System of Color Specifications
• Impossibility to oserve color or judge color with
unaided eyes at normal condition led to the
addition of informations like standard observer.
• It is possible to calculate tristimulus values (i.e.
the amounts of three primaries [X,Y and Z] which,
if additively mixed, would match a colour) of a
samplespecified.
• The CIE had to define standard primaries,
standard light sources and a standard observer,
together with standard observing and viewing
conditions.
10. Standard primaries
• SE = equal-energy stimulus, i.e. a stimulus
having equal amounts of energy at all
wavelengths through the visible spectrum.
= Standard for Sensitivity of Eye to light of different
wave length
11. Standard light sources and Standard
illuminants
• The appearance of color, depends on the light
source.
• Source is a physical emitter of light such as
the sun or a lamp.
• Illuminant refers to a specified spectral
energy distribution. (Light is a form of
Energy, in the spectrum of Electromagnetic
radiation)
12. Fundamentals for Illuminants
• Blackbody: A blackbody refers to an opaque
object that emits thermal radiation.
A perfect blackbody is one that absorbs all
incoming light and does not reflect any.
At room temperature, such an object would
appear to be perfectly black (hence the term
blackbody).
• A blackbody is a theoretically ideal radiator
and absorber of energy at all electromagnetic
wavelengths.
13.
14. Fundamentals for Illuminants
• Black Body Radiation: The Energy emitted by a
blackbody. Higher the Temperature shorter is the
wave length.
16. Fundamental of Illuminants
• Planckian Locus: In a CIE color space diagram,
the plot of chromaticity coordinates of a
blackbody radiator with temperatures from
1000 to 20,000 K is called Planckian locus.
• Colors on this Locus between 2,000 to 20,000
are considered “white”, with 2,000 (warm
white) being reddish white and 20,000 being
blueish white. (Cool white)
17. Fundamental of Illuminants
• Corelated Color Temepature (CCT): CCT
describes the colour temperature of those
white light sources (non blackbody emitters
like LED and Fluorescent lamps) whose colours
don’t fall exactly on the Planckian locus.
• The CCT of a non-Planckian light source is the
blackbody colour temperature that the source
resembles most closely.
18. Standard illuminants
• Standard Illuminant A: It represents Black
body radiator at an absolute temperature
2856K.
• Source A can be realised by gas-filled coiled
tungsten filament lamp operating at a
correlated color temperature of 2856 K.
19. Standard illuminants
• Standard Illuminant B and C: B Represents
Direct Sunlight with CCT 4874 K.
• C Represents Average Sunlight with CCT 6774
K.
• Neither B or C represents real daylight in the
near UV region.
• The amount of light of any one wavelength
reaching the eye is proportional to the energy
of the source multiplied by the reflectance
factor
20. Standard illuminants
• Illuminant D65 is based on measurements of
the total daylight (i.e. sun plus sky) in a
number of countries.
• Except for times near sunrise and sunset, the
relative spectral energy distribution generally
corresponds to correlated colour
temperatures between 6000 and 7000 K.
• D illuminants
– D65 (for textiles)
– D50 (for graphic arts)
22. Standard Illumination and viewing
Conditions
• The original CIE recommendation was that the
sample should be illuminated at 45° to the
surface and the light viewed normally, i.e. at
right angles to the surface.
• This mode can be represented 45/0.
• It was assumed that the opposite mode (0/45)
would give the same result, but this is not the
case if the incident light is polarized
23. Standard Illumination and viewing
Conditions
• Four possible sets of conditions:
• These are 45/0, 0/45, d/0 and 0/d.
• In the third case (d/0) the sample is
illuminated by diffuse light
• In the last case (0/d) it is the light reflected at
all angles is collected (using an integrating
sphere, as in many spectrophotometers).
24. Standard Reflectance Factor
• Instrument manufacturers supply calibrated
white tiles with their instruments. Using
these, corrected R values are obtained
automatically.
25. Tristimulus Value and Color
• Y tristimulus value should roughly represent
the lightness of a sample, i.e. the higher the Y
value, the lighter the sample appears.
• Y = 80, ;Sample will appear light
• Y = 3, the sample will look dark.
26. CIE System
• The CIE tristimulus values for a sample are
related to the colour of the sample, but ignore
other important features such as surface
texture, gloss,sheen, etc.
• Thus a gloss paint sample and a matt paint
sample might have the same tristimulus
values, but obviously will not look the same.
Editor's Notes
The CIE system basically attempts to tell us how a colour might be reproduced (by a mixture of three primary light sources) rather than described.
The amounts of the three primaries required to match a particular colour provide a numerical specification of that colour.
A green colour corresponding to 546.1 nm could be produced even more easily.
A mercury lamp emits light at only four wavelengths in the visible region (404.7 nm, 435.8 nm, 546.1 nm and 577.8 nm). By filtering out the other three, the required green wavelength could be obtained.
It is important to realise that the colour of an object depends on the light source used to illuminate its surface, the particular observer who views it, as well as the properties of the surface itself. The nature of the surface is the most important factor.
Note that there is no way in which the two colours interact with each other.
Red and Green are single wavelengths, both the wavelengths reach our eye and are not interfered with in any way by each other.
The only restriction in the choice of primaries being that it must not be possible to match any one of the primaries using a mixture of the other two.
However, there is no set of real primary colours that can be used to match all colours using positive amounts of the primaries, i.e. there is no set of real primaries that will eliminate negative tristimulus values entirely.
The only restriction in the choice of primaries being that it must not be possible to match any one of the primaries using a mixture of the other two.
However, there is no set of real primary colours that can be used to match all colours using positive amounts of the primaries, i.e. there is no set of real primaries that will eliminate negative tristimulus values entirely.
It is possible to calculate tristimulus values (i.e. the amounts of three primaries which, if additively mixed, would match a colour) of a sample
specified. The CIE had to define standard primaries, standard light sources and a standard observer, together with standard observing and viewing conditions.
Real colours can be matched using positive amounts of the chosen primaries (X), (Y) and (Z).
700 nm = Red 546.1 nm = Green 435.8 = Blue
The amount of light reflected, and hence the appearance, depends on the light source. In practice, we use many different light sources, particularly various phases of daylight, and various types of fluorescent tube and tungsten light.
Thus an illuminant can readily be specified, but may not be realisable in practice. In calculating tristimulus values from reflectance values, the tabulated energy distribution is used, but may be different from the actual distribution of the light source in the spectrophotometer.)
This takes the form of an electromagnetic field having an intensity-versus-wavelength relation whose graph looks like a skewed, bell-shaped statistical curve. The maximum point on the curve shows the wavelength at which the radiation intensity is greatest.
This wavelength depends on the thermodynamic temperature , in kelvin s, of the object. The higher the temperature, the shorter the wavelength at which the radiation is most intense
This takes the form of an electromagnetic field having an intensity-versus-wavelength relation whose graph looks like a skewed, bell-shaped statistical curve. The maximum point on the curve shows the wavelength at which the radiation intensity is greatest.
This wavelength depends on the thermodynamic temperature , in kelvin s, of the object. The higher the temperature, the shorter the wavelength at which the radiation is most intense
In a CIE colour space diagram, the plot of the chromaticity coordinates of a blackbody radiator with temperatures from 1,000 to 20,000 Kelvin is called the Planckian locus. Colours on this locus in the range from about 2,000 to 20,000 K are considered to be “white”, with 2,000 K being reddish white (“warm white”) and 20,000 K being bluish white (“cool white”).
Other, more energy efficient light sources – such as fluorescent or discharge lamps, or LEDs – are not blackbody or incandescent sources. Taking one example, LEDs emit light by a process called electroluminescence. v The chromaticity coordinates of the white light emitted by an LED will not necessarily fall directly on the Planckian locus in the colour space diagram. For those light sources, we should refer to them as having a correlated colour temperature (CCT) . CCT describes the colour temperature of those white light sources (non blackbody emitters) whose colours don’t fall exactly on the Planckian locus. The CCT of a non-Planckian light source is the blackbody colour temperature that the source resembles most closely. Correlated colour temperature is also reported in units of Kelvin (K).
The amount of light reflected, and hence the appearance, depends on the light source. In practice, we use many different light sources, particularly various phases of daylight, and various types of fluorescent tube and tungsten light.
Thus an illuminant can readily be specified, but may not be realisable in practice. In calculating tristimulus values from reflectance values, the tabulated energy distribution is used, but may be different from the actual distribution of the light source in the spectrophotometer.)
Wright10 and Guild11 used visual tristimulus colourimeters in which onehalf of the field of view consisted of a mixture of (R), (G) and (B) primaries, while the colour in the other half was light of a single wavelength. To produce a match experimentally, it was necessary to add some of (R), (G) or (B) to the wavelength to be matched.
Each used a somewhat different technique, and in particular different primaries were used. Both considered each wavelength throughout the visible spectrum and averaged results from a number of observers. The results differed from one observer to another (as expected), but when the average results from the two experiments were converted to a common set of primaries, the agreement was considered to be satisfactory.
The results were expressed as the tristimulus values for an equal energy spectrum, i.e. using primaries (R), (G) and (B) the results were expressed as the amounts r¯, g¯ and b¯ required to match one unit of energy of each wavelength throughout the visible region. Since (R), (G) and (B) were real primaries, some of the values were negative. The CIE adopted three unreal primaries (X), (Y) and (Z) and the colour matching functions in terms of these primaries are denoted by x¯, y¯ and Z¯ and are always positive. This ensures that tristimulus values for all real colours are always positive.
The original CIE recommendation was that the sample should be illuminated at 45° to the surface and the light viewed normally, i.e. at right angles
to the surface. This mode can be represented 45/0. It was assumed that the opposite mode (0/45) would give the same result, but this is not the
case if the incident light is polarized17. Four possible sets of conditions are now recommended. These are 45/0, 0/45, d/0 and 0/d. In the third case
the sample is illuminated by diffuse light while in the last case the light reflected at all angles is collected (using an integrating sphere, as in many
spectrophotometers).