7 hours ago
I have some satellite imagery of the same area bur from different times. I want to show where development has occurred.
The satellite images are all the the same extent but come from different sources and look a lot different from one another. While the changes in developed areas is visible it gets lost in all the other differences in the images.
I thought it might be best to use edge detect with the magic wand to select the developed areas in another layer and then turn it to just black and white, then change the colors of that area to some other color. I also thought because the satellite images were quite variable in how they looked, some were nice and full color others were more black and white and some it looks like some tiles were color and others more grayscale.
I could do that. I later thought I'd colorize the base grayscale layer to green. It sort of matches what I'm trying to show and gets lost even in the full color images when I go to grayscale.
I find though that when I overlay the layer with just the developed areas with an alpha background that the bottom colorized layer loses it colorization. I read something about turning the alpha lock on so I did that for the base layer and also the top layer and that didn't change anything. It went from colorized back to grayscale.
Does anyone know why it is doing this and how to keep if from doing this.
For that matter, I described what I'm trying to do because I have to think this sort of thing has been done many times by others. Maybe there is another way that is easier or maybe that just works.
I have used GIMP on and off for quite a few years now, but never really for this sort of thing. I'm also using v3.06 for Linux. I think it is a flatpack build as well for what its worth.
The satellite images are all the the same extent but come from different sources and look a lot different from one another. While the changes in developed areas is visible it gets lost in all the other differences in the images.
I thought it might be best to use edge detect with the magic wand to select the developed areas in another layer and then turn it to just black and white, then change the colors of that area to some other color. I also thought because the satellite images were quite variable in how they looked, some were nice and full color others were more black and white and some it looks like some tiles were color and others more grayscale.
I could do that. I later thought I'd colorize the base grayscale layer to green. It sort of matches what I'm trying to show and gets lost even in the full color images when I go to grayscale.
I find though that when I overlay the layer with just the developed areas with an alpha background that the bottom colorized layer loses it colorization. I read something about turning the alpha lock on so I did that for the base layer and also the top layer and that didn't change anything. It went from colorized back to grayscale.
Does anyone know why it is doing this and how to keep if from doing this.
For that matter, I described what I'm trying to do because I have to think this sort of thing has been done many times by others. Maybe there is another way that is easier or maybe that just works.
I have used GIMP on and off for quite a few years now, but never really for this sort of thing. I'm also using v3.06 for Linux. I think it is a flatpack build as well for what its worth.