Brightness and Lightness
Hi all
The latest inkscape.pot update draw my attention on the terms "Brightness" and "Lightness". I supposed they were the same, but according to the filter names "Brightness, custom (color)" en "Lightness, custom (color)" in the menu "Filters" > "Experimental", there is a difference between brightness and lightness. Can anyone explain the difference, if there is any: is it a different concept, related to color space, different mathematical formula, ... ? Thanks a lot.
Regards Kris
Thanks for your reply ! This kind of advice is particularly useful for me because my English isn't perfect and thus we could find better names together.
The Lightness filter allows to change the luminosity of pictures or objects. Technically it is based on Component transfer Gamma. For example if you increase lights and shadows you obtain a more contrasted image like in the joined example file.
The Brightness filter allows to play with saturation vibration and eventually lightness of the colors (it can do it also with negative or inverted values). This one is based on a simple Color matrix. You can easily obtain very saturated pictures if you increase strength to 2 and decrease vibration to -0,5 (one half of the strength change) ; in the joined example I also decreased luminosity.
These filters are made to quickly obtain strong color effects based on very light code and suited to be applied before or after other filter effects ; as they are very sensitive the best is perhaps to begin with numerical entries (mouse wheel works very well).
Regards, ivan
________________________________ De : Kris De Gussem <kris.degussem@...400...> À : inkscape-devel inkscape-devel@lists.sourceforge.net Envoyé le : Lun 21 mars 2011, 20h 30min 18s Objet : [Inkscape-devel] Brightness and Lightness
Hi all
The latest inkscape.pot update draw my attention on the terms "Brightness" and "Lightness". I supposed they were the same, but according to the filter names "Brightness, custom (color)" en "Lightness, custom (color)" in the menu "Filters" > "Experimental", there is a difference between brightness and lightness. Can anyone explain the difference, if there is any: is it a different concept, related to color space, different mathematical formula, ... ? Thanks a lot.
Regards Kris
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My question was only intended as a check (not to give any sort of critics ;-) ). Lightness is mostly, but not only, used for filters. When reviewing the latest modifications in the user messages, I had the feeling that terms "brightness" and "lightness" were not used consequently throughout Inkscape. For example, it seemed weird to me to use lightness or HSL in the Create Tiled Clones dialog. After I read http://en.wikipedia.org/wiki/HSL_and_HSV I conclude that there is not an issue with the usage of these terms.
Regards Kris
2011/3/21 Ivan Louette <ivan_louette@...48...>:
Thanks for your reply ! This kind of advice is particularly useful for me because my English isn't perfect and thus we could find better names together.
The Lightness filter allows to change the luminosity of pictures or objects. Technically it is based on Component transfer Gamma. For example if you increase lights and shadows you obtain a more contrasted image like in the joined example file.
The Brightness filter allows to play with saturation vibration and eventually lightness of the colors (it can do it also with negative or inverted values). This one is based on a simple Color matrix. You can easily obtain very saturated pictures if you increase strength to 2 and decrease vibration to -0,5 (one half of the strength change) ; in the joined example I also decreased luminosity.
These filters are made to quickly obtain strong color effects based on very light code and suited to be applied before or after other filter effects ; as they are very sensitive the best is perhaps to begin with numerical entries (mouse wheel works very well).
Regards, ivan
De : Kris De Gussem <kris.degussem@...400...> À : inkscape-devel inkscape-devel@lists.sourceforge.net Envoyé le : Lun 21 mars 2011, 20h 30min 18s Objet : [Inkscape-devel] Brightness and Lightness
Hi all
The latest inkscape.pot update draw my attention on the terms "Brightness" and "Lightness". I supposed they were the same, but according to the filter names "Brightness, custom (color)" en "Lightness, custom (color)" in the menu "Filters" > "Experimental", there is a difference between brightness and lightness. Can anyone explain the difference, if there is any: is it a different concept, related to color space, different mathematical formula, ... ? Thanks a lot.
Regards Kris
Colocation vs. Managed Hosting A question and answer guide to determining the best fit for your organization - today and in the future. http://p.sf.net/sfu/internap-sfd2d _______________________________________________ Inkscape-devel mailing list Inkscape-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/inkscape-devel
Thanks for your reply ! I am glad to know these names aren't too bad.
And don't hesitate to give a try to the new experimental custom filters. Nicolas Dufour and me are very interested in getting advices.
Kind regards
ivan
________________________________ De : Kris De Gussem <kris.degussem@...400...> À : Ivan Louette <ivan_louette@...48...> Cc : inkscape-devel inkscape-devel@lists.sourceforge.net Envoyé le : Mer 23 mars 2011, 22h 50min 17s Objet : Re: Re : [Inkscape-devel] Brightness and Lightness
My question was only intended as a check (not to give any sort of critics ;-) ). Lightness is mostly, but not only, used for filters. When reviewing the latest modifications in the user messages, I had the feeling that terms "brightness" and "lightness" were not used consequently throughout Inkscape. For example, it seemed weird to me to use lightness or HSL in the Create Tiled Clones dialog. After I read http://en.wikipedia.org/wiki/HSL_and_HSV I conclude that there is not an issue with the usage of these terms.
Regards Kris
2011/3/21 Ivan Louette <ivan_louette@...48...>:
Thanks for your reply ! This kind of advice is particularly useful for me because my English isn't perfect and thus we could find better names together.
The Lightness filter allows to change the luminosity of pictures or objects. Technically it is based on Component transfer Gamma. For example if you increase lights and shadows you obtain a more contrasted image like in the joined example file.
The Brightness filter allows to play with saturation vibration and eventually lightness of the colors (it can do it also with negative or inverted values). This one is based on a simple Color matrix. You can easily obtain very saturated pictures if you increase strength to 2 and decrease vibration to -0,5 (one half of the strength change) ; in the joined example I also decreased luminosity.
These filters are made to quickly obtain strong color effects based on very light code and suited to be applied before or after other filter effects ; as they are very sensitive the best is perhaps to begin with numerical entries (mouse wheel works very well).
Regards, ivan
De : Kris De Gussem <kris.degussem@...400...> À : inkscape-devel inkscape-devel@lists.sourceforge.net Envoyé le : Lun 21 mars 2011, 20h 30min 18s Objet : [Inkscape-devel] Brightness and Lightness
Hi all
The latest inkscape.pot update draw my attention on the terms "Brightness" and "Lightness". I supposed they were the same, but according to the filter names "Brightness, custom (color)" en "Lightness, custom (color)" in the menu "Filters" > "Experimental", there is a difference between brightness and lightness. Can anyone explain the difference, if there is any: is it a different concept, related to color space, different mathematical formula, ... ? Thanks a lot.
Regards Kris
Colocation vs. Managed Hosting A question and answer guide to determining the best fit for your organization - today and in the future. http://p.sf.net/sfu/internap-sfd2d _______________________________________________ Inkscape-devel mailing list Inkscape-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/inkscape-devel
participants (2)
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Ivan Louette -
Kris De Gussem