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Questions tagged [perception]

In SO, Perception means what an user believes by observing something.

Perception: Immediate or intuitive recognition or appreciation, as of moral, psychological, or aesthetic qualities; insight; intuition; discernment: an artist of rare perception.

In SO, Perception means what an user believes by observing something. It may apply to perceived speed of a web page, perceived usability etc.

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Formula to determine perceived brightness of RGB color

I'm looking for some kind of formula or algorithm to determine the brightness of a color given the RGB values. I know it can't be as simple as adding the RGB values together and having higher sums be brighter, but I'm kind of at a loss as to where…
robmerica
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What is the shortest perceivable application response delay?

A delay will always occur between a user action and an application response. It is well known that the lower the response delay, the greater the feeling of the application responding instantaneously. It is also commonly known that a delay of up to…
Jon Cram
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How to generate n different colors for any natural number n?

Say n = 100; How do I generate 100 visually distinct colors? Is this mathematically possible?
deostroll
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Perceptual Hash Algorithms in Python or PHP?

I've been exposed via StackOverflow to pHash, a C++ perceptual hash library for audio, video, images, and text fingerprinting - recently with preliminary bindings for PHP, C# and Java. I'm interested in studying these algorithms and I'm wondering if…
Alix Axel
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How to approximate CSS box-shadow property using solid border only?

Please note that the question is not about CSS, rather about imaging, colors and a bit of mathematics. We are not talking here about how to do things in CSS. Make sure your answer does not contain a single line of CSS. Mathematics, tables, images,…
noomorph
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How fast should a dynamically generated web page be created?

I have a number data-driven web based applications that serve both internal and public users and would like to gauge how fast you would expect a page to be created (in milliseconds) in order to maintain user satisfaction and scalability. So, how…
Guy
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Why does the WCAG contrast formula use the luminance and not the perceived lightness?

The WCAG formula/algorithm for determining the contrast between two colors uses the luminance of these colors. That is: sRGB is converted into linear RGB, then the different channels are multiplied with three weights (R 0.2126, G 0.7152, B 0.0722)…
Lukas Kalbertodt
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Crystal Reports on ASP.NET: How to make the first page visible faster

In ASP.NET application, while using Crystal Reports (using the Report Viewer control), the report is visible (or the data in the report) only after the complete data is bound to the report source. If the data is too huge (spanning 50 or hundreds of…
Kangkan
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Using perceptually uniform colormaps in Mayavi volumetric visualization

AFAIK Mayavi does not come with any perceptually uniform colormaps. I tried naively to just pass it one of Matplotlib's colormaps but it failed: from mayavi import mlab import multiprocessing import matplotlib.pyplot as plt plasma =…
crypdick
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Making a metric between colors (perception model) with "difference"

Take a look at the image below. If you're not color blind, you should see some A's and B's. There are 3 A's and 3 B's in the image, and they all have one thing in common: Their color is the background + 10% of value, saturation and hue, in that…
bombax
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Finding the perceptual redundancy inside a color image in matlab

How to find the perceptual redundancy in color images in matlab? Is there any piece of code available or a systematic approach available which can only output the perceptually indiscernible image taking the input of the color image with perceptual…
MSD Paul
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How to load image before javascript

I'm currently looking to improve the perception of a web application by ensuring that the company logo is downloaded ahead of the javascript. To do this I moved the javascript references below the img element for the company logo. For example:
Curtis
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Measuring web page "perception" speed

I know of many tools which measure the speed and performance of a web page, however are there any online tools which can measure the site perceived performance speed? I'm carrying out various front-end performance improvements and would like to…
Curtis
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Face recognition Intel Perceptual Computing

I am a newbie working with INTEL PERCEPTUAL COMPUTING SDK Gold version released in 2013. I am using visual studio 2012 professional version and I am using c++ samples. I have figured out a way to detect faces of people when they come in front of the…
Kandarp Joshi
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jQuery: Increase Perceived Responsiveness During the Ready Event

Launching code on document ready is a pillar of jQuery. But sometimes, lengthy operations will be executed inside the ready event. For example, attaching multiple carousel instances to lengthy unordered lists will take some time. Question: How…
Jim G.
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