color selection and cut

[snico]

Hellot there,

I've been searching for this feature for almost 15 video but nobody seems to use it.

What i need to do is very simple, I need to select a logo on a white backbround, change its color and put it on a transparent background.

What I am struggling to do is: IS THERE A SIMPLE WAY TO SELECT ONE COLOR? Like I say to the program "select everything that is black so i can cut it and put in another document?"

If there is such function can you explain to me where i can find it? I keep searching for tutorials and only find people who does 100+ actions to get this result, when it is really simple the way i explained.

[h_d]

Hiya @snico and welcome! Which Affinity program are you using? Photo, Designer or Publisher? It would also be helpful if you could upload the image you're trying to work on, or a screen grab.

[NotMyFault]

On 4/27/2021 at 12:16 PM, snico said:

...

I need to select a logo on a white backbround, change its color and put it on a transparent background.

What I am struggling to do is: IS THERE A SIMPLE WAY TO SELECT ONE COLOR? Like I say to the program "select everything that is black so i can cut it and put in another document?"

...

Hi,

Assuming your are using Affinity Photo, an pixel layer (not a vector layer), the logo has only one color of one intensity, and no transparency, the logo is on pure white background.

This is only one possible workflow besides unlimited other options:

1. Use the "Flood selection tool" (this is essentially what you are asking for)
2. uncheck "continuous",
3. select the white background,
4. Invert Selection (Ctrl-Shift-I)
5. Duplicate (Ctrl-J)
6. Deselect (Ctrl-D)
7. Hide original layer
8. Select upper layer
9. "Layer effects>Color Overlay"
10. Click into color rectangle (normally black)
11. Adjust Color of your taste
12. Export in a format which supports transparency (e.g. PNG or TIFF)

If you want to preserve lightness levels, you need slightly different steps.

If you need to do this on a regular basis for multiple images, i can provide one-click solutions using more advanced techniques (procedural texture filter).

[NotMyFault]

and this is the promised 1-click solution to:

1.  Remove pure white background (must be RGB 255/255/255)
2. replace all non-white pixels by a selectable RGB color,
3. The pixel brightness is converted into transparency

Just "merge visible" and move it where you need it.

If you background has a different color than white, i can provide an extended version where you can select the color of the background.

 

[Wosven]

If you've got only your logo on a white background, you can do: Filters > Colors > Erase white paper.

When I use this, I usually add a white version of the same log/shape beneath, since some lighter parts become transparent too, and it can be a problem on a colorfull backgrounds.

[NotMyFault]

17 minutes ago, Wosven said:

If you've got only your logo on a white background, you can do: Filters > Colors > Erase white paper.

When I use this, I usually add a white version of the same log/shape beneath, since some lighter parts become transparent too, and it can be a problem on a colorfull backgrounds.

Unfortunately, erase white paper makes all grey pixels semi-transparent, probably using sometheing like A=1-I. This makes is useless for logos using greyscale pixels.

[Alfred]

On 4/27/2021 at 11:16 AM, snico said:

What i need to do is very simple, I need to select a logo on a white backbround, change its color and put it on a transparent background.

Follow these steps to make the white background transparent:

1. Select the layer in the Layers panel

2. Click on the ‘Blend Ranges’ gearwheel at the top of the panel

3. In the Blend Options dialog that pops up, go to the Source Layer Ranges graph

4. Drag the right-hand end of the line all the way down to make the white pixels 100% transparent

At this point any black pixels will still be 100% opaque but everything else will be semitransparent. To restore full opacity to all the non-white pixels, drag the left-hand end of the line straight across towards the right, stopping when the white pixels begin to reappear.

[NotMyFault]

11 minutes ago, Alfred said:

Follow these steps to make the white background transparent:

1. Select the layer in the Layers panel

2. Click on the ‘Blend Ranges’ gearwheel at the top of the panel

3. In the Blend Options dialog that pops up, go to the Source Layer Ranges graph

4. Drag the right-hand end of the line all the way down to make the white pixels 100% transparent

At this point any black pixels will still be 100% opaque but everything else will be semitransparent. To restore full opacity to all the non-white pixels, drag the left-hand end of the line straight across towards the right, stopping when the white pixels begin to reappear.

I like this elegant method 👍

But there is one catch: the result does not get 100% alpha, but stays slightly below,e.g. 254 of 255. This might lead to issues at later steps.

To solve, you might add a levels adjustment on alpha channel) with white level set to 99% or 98...