I have a .jpg original of our company logo:


(partial crop)
I want to re-create it in Inkscape. (for obvious reasons)

The only challenge I have is color-matching the original:

When I use the Color picker I get an exact match, but for an Alpha of 255.
As you can see from the original, the final rectangles need to be partially transparent.
If I Color pick, then slide Alpha (transparency) to 180; I get the transparency, but now the color is no longer a match

When the Color-Picker is selected I appear to get a menu option to modify it's behaviour:


This allows for 3 different settings:

Pick Assign
Pick -
- -

Maybe I'm not doing it right, but none of those permutations result in the behaviour I need:
- Lock the Alpha (transparency) setting on the Fill I am tweaking
- Pick color from .jpg which matches the jpg at the prescribed Alpha setting.

Is there an easy solution that I failed to google?
(I'd hate to have to create non-overlapping shapes to represent each resulting color area)

Norsak wrote:I have a .jpg original of our company logo

A JPEG image has no transparency -> there's nothing to 'pick' a transparency value from with Inkscape's dropper tool (the transparency can be picked if the compositing is done in Inkscape i.e. based on the opacity values of the stacked objects which contribute to the computed style (color value) as rendered on-canvas underneath the mouse pointer position of the dropper tool).

I vaguely recall having seen a tool discussed on deviantArt (in the context of MLP), external to inkscape, which does such kind of color and alpha de-compositioning: Alpha Blending Solver (no idea whether this would work for your case though).

~suv is swift as shadow ,)

options are working on colours within Inkscape. When used on bitmap, nontransparent as in your example, tool can not "read" the transparency since there is none.
To find a match for a transparent colour from bitmap, you`ll either need a level of transaprency or color code of the used colour. Then some math shall be done and - voila! ,)

Check this page for more details regarding the dopper tool and colors in Inkscape.

p.s.
Thanks ~suv for the tip about that tool. It actually might be handy.
Norsak, chime back if you try it out.

Alpha Blending Solver

Good suggestion, impressive that you have something that specific on file.

While it tries to do exactly what I need, it falls a little short on execution.
It get's closer than either Color Picker or me, but it is still off by enough that the human eye can tell.

A JPEG image has no transparency -> there's nothing to 'pick' a transparency value from with Inkscape's dropper tool

True, but that is not what I'm asking of Color Picker. I want to set the transparency. Alpha has 256 possible values, I can handle playing hot-cold in a one dimensional game.
If I declare transparency to be N, and then ask Color Picker: "What RBG values at transparency=N color match this .jpg pixel"... technically there is enough information provided for the program to provide the answer.
Unfortunately that is not an option built into Color Picker.

I ended up parsing old emails, discovering the name of the company that designed the logo, and getting them to email me ...an eps file.
But that is good enough, it means I can generate raster files at any scale (job done).

Thank you for your suggestions, as always I learn something new everytime I come here.

Norsak wrote:If I declare transparency to be N, and then ask Color Picker: "What RBG values at transparency=N color match this .jpg pixel"... technically there is enough information provided for the program to provide the answer.
Unfortunately that is not an option built into Color Picker.

I don't think so.
If you got a purple pixel and you tell the color picker its alpha is 50% how do you want to tell if it's a 50% purple over purple or a 50% red over a blue pixel or a 50% blue over a red pixel (and so on)

I don't think so.
If you got a purple pixel and you tell the color picker its alpha is 50% how do you want to tell if it's a 50% purple over purple or a 50% red over a blue pixel or a 50% blue over a red pixel (and so on)

Good point!
I was wearing blinders because in my example the background is all white.
In the examples which you are describing something like Alpha Blending Solver is the only real way to get at all 4 parameters.

I retract my assumption.