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Bill Anderson
Works at Self Employed
Attended University of Idaho
Lives in San Jose, Costa Rica


Bill Anderson

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Since any screen (monitor, laptop, mobile device, or TV) is a light source, understanding the RGB color space is important. While it represents a small portion of the human color gamut, the sRGB color space is still the common denominator.
The RGB (Red, Green, Blue) color model dates back to 1860 and the Young-Helmholtz trichromatic theory of color vision. In fact, all color models are tied to human color vision. Color models that define a light source, such as...
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Bill Anderson

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Colorblind Pro version 1.1.1 is now in beta channel. The release features the addition of the Machado-Oliveira-Fernandes (MOF) model. While the BVM and MDWW models are based on the Helmholtz theory of color vision, the MOF model is based on the Stages theory of color vision. The MOF model also follows the replacement theory for anomalous trichromatic vision, and not the missing cone theory. This allows for much better simulation of partial loss.
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Released to main channel this morning. Now, I can focus on testing models
with FM DK-15. FM-100 raised additional questions that require more
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Gamma is one those little known factors in color simulation. Yet, it plays an important role. Gamma values have radically changed since the initial simulation studies. Operating systems and the Web have dramatically improved their handling of images, and now handle system gamma. Do models still need to make gamma adjustments?
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Rods and cones are just part of the retina layer of the eye. 
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The article is a bit long, but it is worth taking the time to read, and absorb, the entire article.
If you have ever lost a loved one to suicide, you know the tremendous amount of pain it causes. Years ago, I survived a suicide attempt and spent years receiving treatment in rehab centers and psychiatric hospitals. Now a psychiatric nurse, I have also spend many years working in mental health services. In my experience, nobody commits suicide because they want to die, they commit suicide because they want the pain in their lives to go away... By...
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Testing Colorblind Simulation models is an interesting challenge. A model should simulate human responses to the test conditions. Yet, only one model passed all the tests. I have not found another article that tests the output of the simulation models. This article is just the beginning. More test are coming.
Accurate in what sense? The colors produced in an image do not determine accuracy, for we know that color is an illusion. What counts is the ability to discriminate between different shades of color. We do not know the color ...
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Version 1.1.0 of Colorblind Simulator is now live. This version adjusts the color according to the surrounding brightness. The factor is called gamma. A gamma value of 1.0 is for bright surrounding light. a value of 1.25 is for dim surroundings, and 1.5 for dark surroundings. My app is the only app that allows automatic gamma variation based on the brightness setting for the device. A new level of accuracy in colorblind simulation. 
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While the previous article provided an overview of the physiology of the retina, this article tackles the concept of the illusion of color vision. Again it is an introduction to a vast topic.
Just as the universe is not bound to the human construct of three dimensions, the universe does not have color. As Peter Gouras states in "Webvision: The organization of the Retina and Visual System": "Color vision is an ill...
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I released version 1.0.7 of my Colorblind Simulator app to Google Play and Amazon this morning. Version 1.0.7 completes my original vision of 1.0.x, with a few additions.

While testing the app with a Bluetooth keyboard, I tested an alternate means of navigation via entering URLs in the Chrome browser. It does not work in Amazon's Silk browser. If you have the app installed, the links at the bottom of the attached page should work.
Color Vision Deficiency (CVD) alters how an individual perceives colors. The severe forms of CVD are known as color blindness. Colorblind individuals are unable to distinguish different colors depending on the type of color blindness. Individuals with partial color loss are often unable to ...
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Author, Web site developer
Linux, Android, Java, PHP, Drupal
  • Self Employed
    Consultant, present
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
San Jose, Costa Rica
Just an old geek
Air Force veteran from Vietnam era. Member of the American Legion. Became a ham radio operator in the 6th grade. My call sign is WW7BA.

Became involved with Unix in 1978, and Linux in 1996. I have written five books, and numerous course on Unix, Linux, Java, PHP, Perl, Shell programming, and web development.

Currently writing technology articles for my Android News for Costa Rica website. Developing Colorblind Simulator apps for Android consumes most of my time.
Bragging rights
Graduated from University of Idaho. Red Hat Certified System Administrator. Vietnam era veteran.
  • University of Idaho
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William F. Anderson
Bill Anderson's +1's are the things they like, agree with, or want to recommend.
To Gamma or not to Gamma

Directly or indirectly, Gamma adjustment is part of most color vision simulation models. Since Gary W. Mayer and Donald P. Greenberg wrote "

Colorblind Simulator | Android News for Costa Rica

Color Vision Deficiency (CVD) alters how an individual perceives colors. The severe forms of CVD are known as color blindness. Colorblind in

AIDE - Android IDE

AIDE - Develop Apps for Android on Android devices

Android News for Costa Rica | Pura Vida with Android

Updated through week 19 **. This FAQ lists the Samsung firmware updates for Latin America. The source of the data are the Twitter feeds from

New Rules in China Upset Western Tech Companies

Stringent regulations, including a requirement to share secret codes, are another form of economic protectionism, Western technology compani

Guide to flashing Samsung firmware | Android News for Costa Rica

This FAQ is limited to flashing Samsung Android devices with Samsung firmware. Even though there is always a risk of failure, flashing new f

Changing the Samsung CSC product code | Android News for Costa Rica

The Customer Service Code (CSC) plays an important role in the operation of your Samsung mobile device. Different countries have different s

Samsung firmware updates for Latin America - week 48 | Android News for ...

During week 48, firmware for the Samsung Galaxy A3 (SM-A300H and SM-A300M) appeared in Latin America. Of the nine firmware releases for olde

Android USB Connections Explained: MTP, PTP, and USB Mass Storage

Older Android devices support USB mass storage for transferring files back and forth with a computer. Modern Android devices use the MTP or

KitKat Update Status for Latin America | Android News for Costa Rica

Google announced KitKat 4.4 on 3 September 2013, and released the firmware for the Nexus 7 in October. KitKat is less than a year old, and i

Learn the details of your Samsung phone | Android News for Costa Rica

While helping a reader with a multi-csc product code, I realize that not everyone is ready to use a terminal emulator app. This led me to a

Debugging SE Android avc messages | Android News for Costa Rica

The acronym AVC refers to the Access Vector Cache, which stores the access vector decisions made by the sepolicy engine of the Linux kernel

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Updated 29/09/2014. Does your Samsung mobile device have the latest firmware? There are many Samsung mobile devices, with firmware variation

SE Android commands | Android News for Costa Rica

SE Android supports a subset of the SELinux commands. Furthermore, the SE Android commands do not support all the options available in the e

Understanding SE Android policy files | Android News for Costa Rica

The "Fundamentals of SELinux" FAQ discussed SELinux as an implementation of Mandatory Access Control (MAC). SELinux uses Type Enforcement® i

Fundamentals of SELinux | Android News for Costa Rica

SELinux does not replace the existing Linux permissions. Instead, SELinux enhances the existing permissions to provide a more granular acces

Samsung firmware updates for Latin America - week 41 | Android News for ...

A last minute burst of firmware update for the Galaxy Grand Neo (GT-I9060L) made week 41 a record breaking week for Samsung firmware release

Samsung firmware updates for Latin America - week 40 | Android News for ...

With 49 Samsung firmware releases in Latin America, week 40 was a normal week. A few of the KitKat 4.4.2 firmware releases were for older mo

Installing an alternate keyboard | Android News for Costa Rica

Changing keyboards in Android is not hard. You can have multiple keyboards, and change them according to your input needs. You perform the s

Samsung firmware updates for Latin America - week 38 | Android News for ...

Where week 37 set the record for the least number of Samsung firmware releases for Latin America, week 38 set the record for the most firmwa