I have an
bpm 8-bit indexed image. I've extracted color palette from it in
Photoshop but to my surprise it turned out that the palette includes much more colors than i can see used in the image. Is it normal? Does it mean that the image doesn't have to use every color from it's palette? Can the palette have "unused" colors?
I know that it could be rather super basic question, but I'm really beginner in the topic.
I have an
Yes, you can have unused colors in a palette, but normally depends on how the file was created in the first place.
Normally a file is analyzed to calculate which colors should be used given the parameters you are defining. For example, some programs can define the number of colors on the palette, let's say you only want 50 colors out of the 256.
After the conversion imagine you keep working on the file painting here and there, erasing some pixels of some colors on the file. The palette is already defined, and now you have some colors on the palette that are not present on the file.
Sometimes you can also define a generic palette, For example, an old "Web Safe" palette that included a wide arrange of colors in defined increments. Your image could have used only a bunch of these colors, and not all of them.