Are there any default or plugin effects that make the edges less pixelated?

[Bobby G]

 

Doing it manually would take time and I always miss something, I would like to know if there is any effect that helps to make the edges less pixelated. In this image I use 3 layers, sea, land, political. It looks like it's small, but I've increased the image size and the pixels turn into large clusters of pixels into a square.

[MJW]

There are at least two plugins that may help: dpy's AA's Assistant and pyjo's Basic Anitalias. However, both work only with "objects," which means groups of non-transparent pixels on a transparent background. So you'll need to make the background (water) transparent rather than the blue-gray color. That should be pretty easy for this example, since the color is pretty solid.

 

• Use the Color Picker to sample the grayish background color.
• Add a new layer beneath the map layer and fill it with the background color. Disable this layer so that the next steps are clearer.
• Use the Magic Wand in Global mode to select the background color. Adjust the tolerance to select all the background pixels.
• Delete the selection.
• Run one or the other (or both) the antialias plugins.
• Enable the colored background.

EDIT: I don't know if you're showing a magnified version, but if not, each block is about ten pixels in size, and the antialiasing plugins aren't going to help with that. You'll first need to resize the image down so that the blocks are pixel in size. In fact, if your pixels are that large, resizing to one pixel per block, then resizing back to the original size will probably smooth things out provided you use the default resize method.

 

EDIT 2: I really need to read more thoroughly, since I completely overlooked the explanation at the end of the comment that the image already consists of separate layers, and that it's magnified. So assuming the blocks before magnification represent single pixels, you can try running the antialiasing plugins on the non-sea layers.

[Red ochre]

4 hours ago, Bobby G said:

It looks like it's small, but I've increased the image size

The shades of green in the mountains are also very 'pixellated' - could the problem be the way in which you re-sized from the smaller image?
Did you use 'nearest neighbour' quality when 'best quality' may have been better?

 

- Only a thought, perhaps not relevant.🙂

[ardneh]

This is the single layer image that you posted with Effects > Noise > Median applied with settings:

Radius 8
Percentile 50

Edited July 25, 2022 by ardneh