Commons:Graphics village pump/February 2024

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CIE Chromaticity conversion

Wondered if I could get any assistance with CIE Chromaticity information, and converting it into either RGB or hexadecimal colors, coordinates are given as x and y values, with luminance factor β. It's using the 1931 standard colorimetric system.

Example of value in question:

y < 0.290 + 0.080 x
y > 0.920 - x
y > 0.559 - 0.394 x
y > 0.316
   0.07 < β < 0.15

I have four colors I'm trying to convert for graphics I'm preparing for the Commons, and I'm at a loss on how to work with the CIE charts in any form, and can't work out how to use a online converter with the information I have.

(Also open to moving the request elsewhere, if someone knows of a better place to ask it.) -- The Navigators (talk) 07:20, 12 February 2024 (UTC)

This looks like xyY colorspace - Scaling β to Y might be a hint. ShakespeareFan00 (talk) 13:08, 13 February 2024 (UTC)
What's the source? ShakespeareFan00 (talk) 13:19, 13 February 2024 (UTC)
The values above appear to define toleranceings, not direct colors.. hmm ShakespeareFan00 (talk) 14:07, 13 February 2024 (UTC)

see - https://www.symbolab.com/solver/inequalities-calculator/y%20%3C%200.290%20%2B%200.080%20x%2C%20y%3E%200.316%2C%20y%3E%200.599-0.394x%2C%20y%3E%200.920-x%2C%20x%3E0?or=input.

Try values around 0.636,0.333, I'm not sure how to factor in the luminance beta.. ShakespeareFan00 (talk) 14:07, 13 February 2024 (UTC)

@The Navigators: - https://support.hunterlab.com/hc/en-us/articles/202024565-What-is-a-Y-Brightness-Beta-Reflectance-Factor-Reflection-Coefficient - With some tweaking I get d71102. If this is meant to be Signal Red from BS381c, the Department of Transport has a specfic conversion to RGB/print for this. ShakespeareFan00 (talk) 14:29, 13 February 2024 (UTC)

@ShakespeareFan00: The source is ISO R 557, possibly the first ISO safety color standard, from 1964. I think it's a tolerance, not an exact color. They seemed to like doing that back then, there's a USA Dept. of Labor document on safety colors that does something similar. ISO R 557 doesn't make any references to color standards, annoyingly. I'll take another look at it with your suggestions tonight, going to be really annoyed if it's just the ISO 3864 colors. Thank you.--The Navigators (talk) 19:19, 13 February 2024 (UTC)
Just realized that it was ISO R 408. ISO R 557 was the related standard for symbols, not colors.--The Navigators (talk) 01:41, 15 February 2024 (UTC)
BTW be aware that some xyY data of earlier eras, used Illuminant C, whereas sRGB uses a later D65, if it looks off, you might need to adjust what reference point is being used. BTW If you can figure out color spaces, I have a BIG project need ing color samples.. ShakespeareFan00 (talk) 19:30, 13 February 2024 (UTC)

Starting line charts

Hi! I would like to know how to start line charts in Commons that are also easy to update. I've reviewed Commons:Convert tables and charts to wiki code or image files and Commons:Convert tables and charts to wiki code or image files, but I'm not sure if I've found an adequate resource.

In short, I would like to convert data from a table and making it more accesible than a screenshot from Microsoft Excel, for example. Many thanks in advance. NoonIcarus (talk) 11:55, 14 February 2024 (UTC)

Concept of my spreadsheets
One can export charts from Microsoft Excel into formats such as PNG (acceptable in Commons) and SVG (preferred in Commons). Separately, I've designed a set of Excel spreadsheets that automatically generate SVG charts, a shortcoming of which being that they're not as friendly as commercial products and they're text-only (no cursor drag-and-drop, etc). Details are at User:RCraig09/Excel to XML for SVG. Other users will undoubtedly have useful suggestions. RCraig09 (talk) 18:13, 14 February 2024 (UTC)
@RCraig09: Just reading this, thank you so much! I will definitely take a look at it. Best wishes, --NoonIcarus (talk) 01:57, 27 February 2024 (UTC)

SVG text with tspan tags is misplaced

All text elements should be centered.

All text elements in the image shown on the right should be centered. But this fails, when there are tspan tags. (So formulas with an exponent can not be centered.) This bug seems to be specific to Commons. Compare question on Stackoverflow. Watchduck (quack) 20:53, 24 February 2024 (UTC)

Looks like the old text-chunk bug that WMF reintroduced in April 2023 when it switched from (IIRC) a three-year old version of rsvg to a five-year old version of rsvg. There's a Phabricator ticket and a very recent community poll to fix it. I'm headed out the door now. Glrx (talk) 15:43, 25 February 2024 (UTC)