process_icons.sh

#!/bin/sh
#
# A post-build script for running in Xcode, to overlay app icons with some build info.
# Requires ImageMagick to be installed before use.

commit=`git rev-parse --short HEAD`
branch=`git rev-parse --abbrev-ref HEAD`
version=`/usr/libexec/PlistBuddy -c "Print CFBundleVersion" "${INFOPLIST_FILE}"`

function processIcon() {
    export PATH=$PATH:/usr/local/bin
    base_file=$1
    base_path=`find "${SRCROOT}" -name $base_file`
    
    echo "Processing $base_path"
    
    if [[ ! -f ${base_path} || -z ${base_path} ]]; then
    return;
    fi
    
    target_file=$base_file
    target_path="${CONFIGURATION_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/${target_file}"
    
    if [ $CONFIGURATION = "Release" ]; then
    cp "${base_path}" "$target_path"
    return
    fi
    
    width=`identify -format %w "${base_path}"`
    
    # This overlays a horizontal band across the icon, containing information
    # about app version, configuration name, branch name, and commit number.
    convert -background '#FFFB' -fill black -gravity center -size ${width}x55\
    caption:"${version} ${CONFIGURATION} ${branch} ${commit}"\
    "${base_path}" +swap -gravity south -composite "${target_path}"
    
    echo "Overlayed ${target_path}"
}

# Replace these with the actual filenames of all your icons
processIcon "app_icon_57x57_square.png"
processIcon "app_icon_72x72_square.png"
processIcon "app_icon_76x76_square.png"
processIcon "app_icon_114x114_square.png"
processIcon "app_icon_120x120_square.png"
processIcon "app_icon_144x144_square.png"
processIcon "app_icon_152x152_square.png"