How To Do Hdr Effect In Gimp Fix Washed Out Pictures Gimp

Color to Alpha with GIMP 2.10 leads to done out appearance

2020-04-fourteen

The original image, which we want to make transparent but not change the values of blackness and white.

I like to employ GIMP (GNU Prototype Manipulation Programme) to create and edit images because information technology is complimentary software, it's easy to install on Debian, and it is fun to apply when you get the hang of it. GIMP is excellent software for editing images.

I affair I rely on is the "Color to Blastoff" function. This allows you to take a flat paradigm and remove a certain colour from it, replacing that colour with transparency.

A common job using this function is to decrease all white from an image, and replace the white with transparency. And then add back a white layer under the transparent layer, and the image looks the aforementioned as it did before, but now separated onto 2 layers. Y'all tin pigment nether the original prototype.

For the purposes of a demo, here is an example black and white image which we would like to plow transparent:

GIMP 2.10 changes Colour to Alpha

Using Color to Alpha in GIMP 2.10 leads to a washed out appearance when the image is reassembled

When I got GIMP 2.10, I noticed the Colour to Alpha did not give the reliable results that I had used many times.

If I took an image, removed the white, and put a white layer underneath, I should go the exact same paradigm dorsum. This is how it worked in GIMP two.viii. But in GIMP 2.10, the result was noticeably washed out looking:

Another related problem in GIMP 2.10

Because Color to Blastoff was not working reliably, I tried an alternative strategy using layer masks.

Convert the epitome to black and white. Invert the colors. Create a new layer and make full it with black. Add a layer mask. Copy the inverted layer and paste it in as the layer mask. Add a white layer under the blackness layer.

The result should look just like the original blackness and white image. But it does not, information technology looks done out and like the layer mask has been inaccurately practical.

I believe this is just another way to arrive at the same problem nosotros have already described.

Online search for answers

Online search for answers turned upward this post.
Click to enlarge

I searched online for this problem, and found several people who had the same problem, simply did not find an respond.

Color to blastoff tool makes done out colors
Need help with 2.x's color to blastoff tool.

Next I searched once again using a slightly unlike approach and ended up reading a thread that talked about changes to GIMP two.10 that are acquired past irresolute the graphics framework to GEGL (Generic Graphic Library). GEGL is the new graphics framework for GIMP that is graph-based and not-destructive.

Now I found a post by Elle that suggests the problem has to do with new default blend modes for layers. See side by side image for the total post I idea was the most useful. And here is a link to the actual post where I found information technology:

GIMP 2.10 Default vs Legacy

Fixing Color to Alpha for GIMP ii.10

Change the Composite Mode on the transparent layer to RGB Perceptual to return the epitome to normal.

Hither is my style to work with Colour to Alpha in GIMP 2.10:

Start with a new flat image.
Use Colour to Blastoff to remove white from the image.
Add back a white layer nether the newly transparent layer.
If the event looks washed out:
- Right click on the done out layer in the layers dialog.
- Under Composite Space, choose "RGB (Perceptual)"
The prototype should now look right.

This makes the Color to Alpha function work again like it did before, which is great because it's very useful.

I used the "compare" tool of imagemagick to compare the new image to the original, and according to compare the images are now identical.

compare image1.png image2.png difference.png

Decision

Color to Alpha is working once again in GIMP 2.10
Let the games begin!

I don't know enough near what the different blend modes are to know whether the new default blend style is just wrong for what I'm doing, or something more alike to a bug. It seems to me the behavior of Colour to Alpha that I am accustomed to is more correct.

I mainly want to get this answer out in that location and then people can detect it. When I searched I did not observe a clear workaround.