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If any color enthusiasts here are frustrated by the lack of perceptual uniformity in every colorspace in common use, I wrote some utility code to work with the

If any color enthusiasts here are frustrated by the lack of perceptual uniformity in every colorspace in common use, I wrote some utility code to work with the Munsell color system -- the only color system produced entirely from measurements of human color perception (with all the noisiness/messiness that entails). You still run up against the limits of your color gamut pretty quickly, though. https://github.com/mrgriscom/munsell https://github.com/mrgriscom/munsell https://en.wikipedia.org/wiki/Munsell_color_system https://en.wikipedia.org/wiki/Munsell_color_system http://www.brucelindbloom.com/index.html?MunsellCalcHelp.html#UPAttributes http://www.brucelindbloom.com/index.html?MunsellCalcHelp.htm...

TheRealPomax 11y ago
Someone on reddit also pointed out https://github.com/CarVac/filmulator-gui https://github.com/CarVac/filmulator-gui which looks like a super cool utility for getting "natural" colour control over your RAW files. I'll be playing with it over the weekend, but the author was pretty positive colours come out looking much more like what they should.
- mrgriscom 11y ago
  Part of me cringes at jumping through all these hoops to recreate some sort of anachronistic aesthetic which probably only looks better to you because it's what you're used to. It reminds me of how electric cars program in a 'jolt' when you hit the accellerator so that it feels more like an ICE. Otoh, I admire the technical effort that goes into reproducing it! Reminds me of the old terminal emulation in xscreensaver: http://www.jwz.org/blog/2003/05/xscreensaver-410-out-now/ http://www.jwz.org/blog/2003/05/xscreensaver-410-out-now/ Also, I've noticed the photos from my Canon point-and-shoot have quite a film-like quality to them.
  - TheRealPomax 11y ago
    yeah except in this case I'm hoping it actually ends up matching what I'm holding in my hand. 500+ fountain pens inks. Anything that actually works (because colour calibration between my cameras and monitors sure doesn't), I'll take. (that tool was written, as far as I understood from the author, to actually get things to look they way they look. Not "the way we were used to". I haven't used film in over a decade. I just want realistic colours.
leni536 11y ago
>the only color system produced entirely from measurements of human color perception What is CIE LAB then? While Wikipedia states that it was influenced by the Munsell color system, I don't think it was directly derived from it. Also I would argue that it is in common use. On the other hand these measurements measured the local distance between colors (based on distinguishability) but nothing guarantees that the space of perceivable colors is Euclidean in this metric. So you can fabricate an Euclidean space of colors where the Euclidean distance is close to the perception distance, but it may never be perfect. Side note: there is no perceivable color space to "rule them all", even if you can fabricate a perfect one. For upscaling images it could make sense to use a perception based colorspace for interpolating pixel values, however for downscaling you should use a linear colorspace (note: sRGB is NOT linear, almost all desktop software downscales wrong [2]). It causes kind of a hassle that distinguishing colors of large areas is happening with a strange metric, but if you are looking at objects with fine structure (like your LCD monitor) then the color mixing happens in a linear colorspace. [1] https://en.wikipedia.org/wiki/Lab_color_space https://en.wikipedia.org/wiki/Lab_color_space [2] http://www.4p8.com/eric.brasseur/gamma-1.0-or-2.2.png http://www.4p8.com/eric.brasseur/gamma-1.0-or-2.2.png
- icegreentea 11y ago
  Funny, I just watched a Scipy conference talk/video about this - it's about finding a new default color map for matplotlib [1] CIE LAB is basically a ~30 year old model based on human perception - basically it takes into account white point adjustment and the non-linear human brightness response, and thats about it. There are newer (and faaar more complicated) models like CIECAM02. [1] https://www.youtube.com/watch?v=xAoljeRJ3lU https://www.youtube.com/watch?v=xAoljeRJ3lU
  - leni536 11y ago
    As I see CIE LAB is not a something "inferior model" to these more complicated models. It just has a more simple viewing conditions model and a more limited regime of validity. It seems somewhat complicated to properly apply CIECAM02. In the case of matplotlib, one should change the line colors depending on the background color being used. Not talking about adapted whitepoint and surrounding too where you at best can make an educated guess. They seem to solve the Euclidean distance problem by embedding in a field with more dimensions. However I'm really happy for these efforts of matplotlib. It is by far my favorite data visualization library. There could be cases where this kind of accuracy is necessary: doctors often diagnose using visual inspection of different camera images (X-Ray, CT, MR). The optimal visualization of these camera images using well crafted colormaps in the right colorspace could save lives.

TheRealPomax 11y ago

Someone on reddit also pointed out https://github.com/CarVac/filmulator-gui https://github.com/CarVac/filmulator-gui which looks like a super cool utility for getting "natural" colour control over your RAW files. I'll be playing with it over the weekend, but the author was pretty positive colours come out looking much more like what they should.

mrgriscom 11y ago
Part of me cringes at jumping through all these hoops to recreate some sort of anachronistic aesthetic which probably only looks better to you because it's what you're used to. It reminds me of how electric cars program in a 'jolt' when you hit the accellerator so that it feels more like an ICE. Otoh, I admire the technical effort that goes into reproducing it! Reminds me of the old terminal emulation in xscreensaver: http://www.jwz.org/blog/2003/05/xscreensaver-410-out-now/ http://www.jwz.org/blog/2003/05/xscreensaver-410-out-now/ Also, I've noticed the photos from my Canon point-and-shoot have quite a film-like quality to them.
- TheRealPomax 11y ago
  yeah except in this case I'm hoping it actually ends up matching what I'm holding in my hand. 500+ fountain pens inks. Anything that actually works (because colour calibration between my cameras and monitors sure doesn't), I'll take. (that tool was written, as far as I understood from the author, to actually get things to look they way they look. Not "the way we were used to". I haven't used film in over a decade. I just want realistic colours.

leni536 11y ago

>the only color system produced entirely from measurements of human color perception What is CIE LAB then? While Wikipedia states that it was influenced by the Munsell color system, I don't think it was directly derived from it. Also I would argue that it is in common use. On the other hand these measurements measured the local distance between colors (based on distinguishability) but nothing guarantees that the space of perceivable colors is Euclidean in this metric. So you can fabricate an Euclidean space of colors where the Euclidean distance is close to the perception distance, but it may never be perfect. Side note: there is no perceivable color space to "rule them all", even if you can fabricate a perfect one. For upscaling images it could make sense to use a perception based colorspace for interpolating pixel values, however for downscaling you should use a linear colorspace (note: sRGB is NOT linear, almost all desktop software downscales wrong [2]). It causes kind of a hassle that distinguishing colors of large areas is happening with a strange metric, but if you are looking at objects with fine structure (like your LCD monitor) then the color mixing happens in a linear colorspace. [1] https://en.wikipedia.org/wiki/Lab_color_space https://en.wikipedia.org/wiki/Lab_color_space [2] http://www.4p8.com/eric.brasseur/gamma-1.0-or-2.2.png http://www.4p8.com/eric.brasseur/gamma-1.0-or-2.2.png

icegreentea 11y ago
Funny, I just watched a Scipy conference talk/video about this - it's about finding a new default color map for matplotlib [1] CIE LAB is basically a ~30 year old model based on human perception - basically it takes into account white point adjustment and the non-linear human brightness response, and thats about it. There are newer (and faaar more complicated) models like CIECAM02. [1] https://www.youtube.com/watch?v=xAoljeRJ3lU https://www.youtube.com/watch?v=xAoljeRJ3lU
- leni536 11y ago
  As I see CIE LAB is not a something "inferior model" to these more complicated models. It just has a more simple viewing conditions model and a more limited regime of validity. It seems somewhat complicated to properly apply CIECAM02. In the case of matplotlib, one should change the line colors depending on the background color being used. Not talking about adapted whitepoint and surrounding too where you at best can make an educated guess. They seem to solve the Euclidean distance problem by embedding in a field with more dimensions. However I'm really happy for these efforts of matplotlib. It is by far my favorite data visualization library. There could be cases where this kind of accuracy is necessary: doctors often diagnose using visual inspection of different camera images (X-Ray, CT, MR). The optimal visualization of these camera images using well crafted colormaps in the right colorspace could save lives.