CIELAB color space | Wikipedia audio article
Channel: wikipedia tts
Date: 03/05/2019

This is an audio version of the Wikipedia Article:
https://en.wikipedia.org/wiki/CIELAB_color_space


00:01:34 1 Advantages
00:01:54 2 Differentiation
00:04:05 3 CIELAB
00:06:05 3.1 Perceptual differences
00:07:15 3.2 RGB and CMYK conversions
00:07:54 3.3 Range of coordinates
00:10:10 4 CIELAB–CIEXYZ conversions
00:10:58 4.1 Forward transformation
00:11:47 4.2 Reverse transformation
00:12:16 5 Hunter Lab
00:12:29 5.1 Approximate formulas for iK/isuba/sub and iK/isubb/sub
00:15:44 5.2 As an Adams chromatic valence space
00:16:35 6 Cylindrical representation: CIELCh or CIEHLC
00:16:50 7 See also
00:17:30 8 References
00:17:35 9 External links
00:19:43 6/29.
00:19:47 Hunter Lab
00:23:57 Approximate formulas for Ka and Kb
00:25:43 As an Adams chromatic valence space
00:30:21 Ka/100 and ke
00:30:40 Cylindrical representation: CIELCh or CIEHLC
00:33:05 0, 120, 240°). Instead, the LCh system uses the four colors yellow, green, blue and red (h
00:34:02 See also



Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago.

Learning by listening is a great way to:
- increases imagination and understanding
- improves your listening skills
- improves your own spoken accent
- learn while on the move
- reduce eye strain

Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone.

Listen on Google Assistant through Extra Audio:
https://assistant.google.com/services/invoke/uid/0000001a130b3f91
Other Wikipedia audio articles at:
https://www.youtube.com/results?search_query=wikipedia+tts
Upload your own Wikipedia articles through:
https://github.com/nodef/wikipedia-tts
Speaking Rate: 0.9435879913605709
Voice name: en-GB-Wavenet-C


"I cannot teach anybody anything, I can only make them think."
- Socrates


SUMMARY
=======
The CIELAB color space (also known as CIE L*a*b* or sometimes abbreviated as simply "Lab" color space) is a color space defined by the International Commission on Illumination (CIE) in 1976.  It expresses color as three values: L* for the lightness from black (0) to white (100), a* from green (-) to red (+), and b* from blue (-) to yellow (+).  CIELAB was designed so that the same amount of numerical change in these values corresponds to roughly the same amount of visually perceived change.
With respect to a given white point, the CIELAB model is device-independent—it defines colors independently of how they are created or displayed.  The CIELAB color space is typically used when graphics for print have to be converted from RGB to CMYK, as the CIELAB gamut includes both the gamuts of the RGB and CMYK color models.
Because three parameters are measured, the space itself is a three-dimensional real number space, which allows for infinitely many possible colors. In practice, the space is usually mapped onto a three-dimensional integer space for digital representation, and thus the L*, a*, and b* values are usually absolute, with a pre-defined range. The lightness value, L*, represents the darkest black at L* = 0, and the brightest white at L* = 100. The color channels, a* and b*, represent true neutral gray values at a* = 0 and b* = 0.  The a* axis represents the green–red component, with green in the negative direction and red in the positive direction.  The b* axis represents the blue–yellow component, with blue in the negative direction and yellow in the positive direction.  The scaling and limits of the a* and b* axes will depend on the specific implementation, as described below, but they often run in the range of ±100 or −128 to +127 (signed 8-bit integer).
The CIELAB color space was derived from the prior "master" CIE 1931 XYZ color space, which predicts which spectral power distributions will be perceived as the same color (see metamerism), but is not particularly perceptually uniform.  Strongly influenced by the Munsell color system, the intention behind CIELAB was to create a space that can be computed via simple formulas from the CIEXYZ space but is more perceptually uniform than CIEXYZ.  When storing color values using limited precision, using a perceptually uniform color space can improve the reproduction of tones.
CIELAB colors are defined relative to the white point of the CIEXYZ space from which they were converted; thus CIELAB values do not define absolute colors unless the white point is also specified.  Often, in practice, the white point is assumed to follow a standard and is not explicitly stated (e.g., for "absolute colorimetric" rendering intent, the International Color Consortium L*a*b* values are relative to CIE standard illuminant D50, while they are relative to the unprinted substrate ...