A blog by Devendra Tewari
A Windows 10 app icon file contains four combinations of image size, alpha, bit depth, and colors. I find the open source ImageMagick 7 particularly helpful, and here’s a recipe for quickly creating an ico file, given a PNG file with enough resolution—I used one with 512x512 pixels, 32-bit depth, and alpha
convert $1 -resize 16x16 -depth 32 16-32.png
convert $1 -resize 32x32 -depth 32 32-32.png
convert $1 -resize 48x48 -depth 32 48-32.png
convert $1 -resize 256x256 -depth 32 256-32.png
convert 16-32.png 32-32.png 48-32.png 256-32.png $2
Save the above bash script and execute with the PNG file path followed by ico file path
./convert.sh image.svg icon.ico