ImageMagick + Pingo

create-app-icons.bat

@echo off

cls

echo Creating 51 app icons, please wait.

im-convert ../../src/assets/images/app-logo-no-gradient.png ^
    ( -clone 0 -resize 2048x1536 -background #1f3165 -gravity center -extent 2048x1536 -write ../../platforms/ios/Assess/Images.xcassets/LaunchImage.launchimage/Default-Landscape@2x~ipad.png ) ^
    ( -clone 0 -resize 2048x1536 -background #1f3165 -gravity center -extent 2048x1536 -write ../screen/ios/screen-ipad-landscape@2x.png ) ^
    ( -clone 0 -resize 1536x2048 -background #1f3165 -gravity center -extent 1536x2048 -write ../../platforms/ios/Assess/Images.xcassets/LaunchImage.launchimage/Default-Portrait@2x~ipad.png ) ^
    ( -clone 0 -resize 1536x2048 -background #1f3165 -gravity center -extent 1536x2048 -write ../screen/ios/screen-ipad-portrait@2x.png ) ^
    ( -clone 0 -resize 1280x720 -background #1f3165 -gravity center -extent 1280x720 -write ../screen/android/screen-xhdpi-landscape.png ) ^
    ( -clone 0 -resize 1024x768 -background #1f3165 -gravity center -extent 1024x768 -write ../../platforms/ios/Assess/Images.xcassets/LaunchImage.launchimage/Default-Landscape~ipad.png ) ^
    ( -clone 0 -resize 1024x768 -background #1f3165 -gravity center -extent 1024x768 -write ../screen/ios/screen-ipad-landscape.png ) ^
    ( -clone 0 -resize 800x480 -background #1f3165 -gravity center -extent 800x480 -write ../screen/android/screen-hdpi-landscape.png ) ^
    ( -clone 0 -resize 768x1024 -background #1f3165 -gravity center -extent 768x1024 -write ../../platforms/ios/Assess/Images.xcassets/LaunchImage.launchimage/Default-Portrait~ipad.png ) ^
    ( -clone 0 -resize 768x1024 -background #1f3165 -gravity center -extent 768x1024 -write ../screen/ios/screen-ipad-portrait.png ) ^
    ( -clone 0 -resize 720x1280 -background #1f3165 -gravity center -extent 720x1280 -write ../screen/android/screen-xhdpi-portrait.png ) ^
    ( -clone 0 -resize 480x800 -background #1f3165 -gravity center -extent 480x800 -write ../screen/android/screen-hdpi-portrait.png ) ^
    ( -clone 0 -resize 480x320 -background #1f3165 -gravity center -extent 480x320 -write ../screen/android/screen-mdpi-landscape.png ) ^
    ( -clone 0 -resize 320x480 -background #1f3165 -gravity center -extent 320x480 -write ../screen/android/screen-mdpi-portrait.png ) ^
    ( -clone 0 -resize 320x200 -background #1f3165 -gravity center -extent 320x200 -write ../screen/android/screen-ldpi-landscape.png ) ^
    ( -clone 0 -resize 200x320 -background #1f3165 -gravity center -extent 200x320 -write ../screen/android/screen-ldpi-portrait.png ) ^
    ( -clone 0 -resize 1024x1024 -write ../icon/ios/iTunesArtwork@2x.png ) ^
    ( -clone 0 -resize 512x512 -write ../icon/ios/iTunesArtwork.png ) ^
    ( -clone 0 -resize 167x167 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-83.5@2x.png ) ^
    ( -clone 0 -resize 167x167 -write ../icon/ios/icon-83.5@2x.png ) ^
    ( -clone 0 -resize 152x152 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-76@2x.png ) ^
    ( -clone 0 -resize 152x152 -write ../icon/ios/icon-76@2x.png ) ^
    ( -clone 0 -resize 144x144 -unsharp 0x1 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-72@2x.png ) ^
    ( -clone 0 -resize 144x144 -unsharp 0x1 -write ../icon/ios/icon-72@2x.png ) ^
    ( -clone 0 -resize 120x120 -write ../icon/ios/icon-40@3x.png ) ^
    ( -clone 0 -resize 114x114 -write ../icon/ios/icon-57@2x.png ) ^
    ( -clone 0 -resize 100x100 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-50@2x.png ) ^
    ( -clone 0 -resize 100x100 -write ../icon/ios/icon-50@2x.png ) ^
    ( -clone 0 -resize 96x96 -write ../icon/android/icon-96-xhdpi.png ) ^
    ( -clone 0 -resize 80x80 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-40@2x.png ) ^
    ( -clone 0 -resize 80x80 -write ../icon/ios/icon-40@2x.png ) ^
    ( -clone 0 -resize 76x76 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-76.png ) ^
    ( -clone 0 -resize 76x76 -write ../icon/ios/icon-76.png ) ^
    ( -clone 0 -resize 72x72 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-72.png ) ^
    ( -clone 0 -resize 72x72 -write ../icon/android/icon-72-hdpi.png ) ^
    ( -clone 0 -resize 72x72 -write ../icon/ios/icon-72.png ) ^
    ( -clone 0 -resize 58x58 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-29@2x.png ) ^
    ( -clone 0 -resize 58x58 -write ../icon/ios/icon-29@2x.png ) ^
    ( -clone 0 -resize 57x57 -write ../icon/ios/icon-57.png ) ^
    ( -clone 0 -resize 50x50 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-50.png ) ^
    ( -clone 0 -resize 50x50 -write ../icon/ios/icon-50.png ) ^
    ( -clone 0 -resize 48x48 -write ../icon/android/icon-48-mdpi.png ) ^
    ( -clone 0 -resize 40x40 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-40.png ) ^
    ( -clone 0 -resize 40x40 -write ../icon/ios/icon-40.png ) ^
    ( -clone 0 -resize 40x40 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-20@2x.png ) ^
    ( -clone 0 -resize 40x40 -write ../icon/ios/icon-20@2x.png ) ^
    ( -clone 0 -resize 36x36 -write ../icon/android/icon-36-ldpi.png ) ^
    ( -clone 0 -resize 29x29 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-29.png ) ^
    ( -clone 0 -resize 29x29 -write ../icon/ios/icon-29.png ) ^
    ( -clone 0 -resize 20x20 -write ../../platforms/ios/Assess/Images.xcassets/AppIcon.appiconset/icon-20.png ) ^
    ( -clone 0 -resize 20x20 -write ../icon/ios/icon-20.png ) ^
null:

echo Finished successfully.

pause

optimise-app-icons.bat

@echo off

cls

echo Scanning app icons for optimisation, please wait.

pingo -s9 -pngpalette=7 ../ ../../platforms/ios/Assess/Images.xcassets/ ../../src/assets/images/

echo Finished successfully.

pause