Use the Photoshop image editing program to fill in the lines of the image. Adobe’s Magic Wand tool lets you select parts of the image that have a solid color. 

This means that according to the Photoshop guide, you can capture the lines of an image without having to follow the outline. In Photoshop, the Stroke function allows you to select the border you want, so when you apply Stroke to image lines, the lines become more colorful and thicker.

Step 1: Open the image you want to edit in Photoshop.

Step 2: Press the W button on the keyboard

And Step 3: Click on a part of the image lines. The selected part of the line appears to flicker. (Optional)

Step 4: Then use to select the rest of the lines in the image and select all the sections.

Step 5: Go to the ” Edit ” menu at the top of Photoshop and select ” Stroke “. Enter the number of pixels you want to add to the line. If it is not black, click on the color box to adjust it. If you are filling in a color line, drag the cursor over the image to activate the color selection tool and click on the color you want to copy from the image. Set ” Location ” to ” Center “. Set ” Blending ” to ” Normal ” and ” Opacity ” to ” 100 “.

Step 6: Click ” OK ” to fill in the lines of the image.

For people who may still be finding this issue I discovered that if you set the tolerance to 0 and click the paint bucket a few times (2 to 3 clicks seems to do the trick for me when working with a hard brush and a resolution of 300) it fills the anti aliasing line without adding an ugly edge to the outside of the original line. (If you have a soft brush or an artistic brush with edge it may not work as well.)

This is much faster than testing out multiple tolerance levels to find some perfect match or trying to use the magic wand with select>modify>expand.

The other option is to toss a layer below the current art layer and clean up the art by quickly painting in the color to fill the gap.

I hope it helps, good luck with your art!