Convert Munsell colors to computer-friendly RGB triplets. The Munsell color system was designed as a series of discrete color chips which closely approximation to the color sensitivity of the human eye. The description of color via three variables tied to perceptible properties (hue, value, and chroma) under a standardized illuminant (sunlight.
Color conversion based on a look-up table of common soil colors.
Arguments
| the_hue | a vector of one or more more hues, upper-case |
|---|---|
| the_value | a vector of one or more values |
| the_chroma | a vector of one or more chromas, may be NA for neutral hues |
| alpha | alpha channel value (for transparency effects) |
| maxColorValue | maximum sRGB color value (see |
| return_triplets | should the function return sRGB triplets instead of an R color |
| returnLAB | should the function return CIE LAB (D65) coordinates |
| color | a |
| colorSpace | Resident evil 1 pc download. the distance metric (colorspace) to use for finding the closest chip: CIE2000 is the most accurate but requires farver >= 2.0.3, Euclidean distance in (CIE)LAB is a close second, while Euclidean distance in sRGB is not at all accurate and should only be used for demonstration |
| nClosest | number of closest Munsell colors to return |
| munsellColor | character vector of strings containing Musell colors, e.g. '10YR 4/3' |
| convertColors | logical, should parsed Munsell colors be converted into sRGB values |
| .. | further arguments to |
Details
These functions generalize to vectorized usage, as long as the length of each argument is the same. Both functions will pad output with NA if there are any NA present in the inputs.
Neutral hues are approximated by greyscale shades ranging from 20% (darker) to 80% (lighter). No chroma is required for neutral hues.
Gley soil colors that are missing a chroma will not be correctly interpreted. Consider using a chroma of 1.
Values of '2.5' (common in soil color descriptions) are silently truncated to '2'.
Non-standard Munsell colors (e.g. '7.9YR 2.7/2.0') can be matched (nearest-neighbor, no interpolation) to the closest color within the `munsell` sRGB look-up table via getClosestMunsellChip(). See examples below.
Note
Care should be taken when using the resulting sRGB values; they are close to their Munsell counterparts, but will vary based on your monitor and ambient lighting conditions. Also, the value used for maxColorValue will affect the brightness of the colors. Th default value (1) will usually give acceptable results, but can be adjusted to force the colors closer to what the user thinks they should look like.
Value
For Munsell to sRGB conversion, a vector of R colors is returned that is the same length as the input data. If return_triplets is TRUE, then a dataframe (of sample length as input) of r,g,b values is returned.
For sRGB to Munsell conversion, a dataframe (NA-padded) of hue, value, chroma, and Euclidean distance to nearest matching color is returned.
References
Examples
We've received almost countless requests for such information as what is the Ral equivalent of Pantone 554 and 228C .. the Munsell equivalent of Ral 5020 and 5009 .. etc., etc.
We suggest that you see:
| affil. link |
We also reprint here a few of the better replies to the inquiries from our finishing.com public forum --
There is probably an easier way, but in the past (converting RGB images to embroidery thread colours) I scanned a colour chart, then used the colour blocks to set up a custom pallet in Photoshop, then told photoshop to convert the image to the custom palet. Alternatively, scan the RAL colours and determine manually which has RGB values closest to yours.
Andy Pugh - UK
The RAL-site official colour-cards are supplied in USA by: DORN COLOR, Inc. Cleveland, OH [Ed. note: see URL near top of page].
Remmelt Bosklopper - Enschede, The Netherlands
All the years I have been working with colours I have never found an exact correlation between these two colour systems [RAL & Pantone]. The best way is to sit down with a RAL and a Pantone colour chart and look for similar colours. If you have a spectrophotometer test the colours on it. The Ral colour range is German. If you type in https://www.ral-farben.de/ral-farben.html?&L=1 this will tell you all you need to know about RAL colours. Alternatively if you just want a colour chart (not exact shade) with RAL colours on it, speak to a friendly paint supplier. (a European Industrial paint supplier is your best bet).
Drew Devlin - North Lincolnshire, UK
Actually RAL and Munsell are using different standard of colors. So no exactly the same color for both. But you can find the closest one. You can use Munsell Conversion color from http://www.xrite.com/product_overview.aspx?ID=1061 then go to www.easyrgb.com/matching.php to find the closest RAL Code.
Rasawulan - Indonesia
Please feel free to follow up by posting any procedural questions you may have in our public forum at www.finishing.com/letters. Sorry, but we cannot post requests for specific color matches across systems because there are virtually an infinite number of combinations and we were getting several such requests every day :-)