Convert an Android boot animation to an animated GIF

boot2gif.sh

#!/bin/bash
################################################################################
#
# boot2gif.sh
#
# DESCRIPTION: Convert an Android boot animation to a GIF
#              You will need ImageMagick to run this script.
#
# USAGE:
#
# boot2gif.sh FILE [OPTIONS]...
#
#  --create-gif                Creates a GIF from the boot animation ZIP archive
#                              The GIF will be created at ./animation.gif
#
#  --create-resized-gif=[SIZE] Create a GIF a resize it.
#                              The SIZE is the GIF's width in pixels
#
#  --create-thumbnail          Finds the best option for a preview/thumbnail.
#                              The image will be created at ./thumbnail.jpg
#
#  --out=[DIRECTORY]           Set the output directory
#

get_image_with_most_colors() {
    local images=$@
    local colors=0
    local histogram_count=0
    local path="";
    for image in $images;
    do
        color_count=$(identify -format %k "$image")
        case $color_count in
            ''|*[!0-9]*)
                continue ;;
            *)
                if [ $color_count -gt $colors ]
                then
                    colors=$color_count
                    path=$image
					histogram_count=$(convert $image rose: -colorspace rgb -colors 10 miff:- | convert - -format "%c" histogram:info: | wc -l)
				elif [ $color_count -eq $colors ]
				then
					# Same amount of colors. Check histogram count
					histogram_line_count=$(convert $image rose: -colorspace rgb -colors 10 miff:- | convert - -format "%c" histogram:info: | wc -l)
					if [ $histogram_line_count -gt $histogram_count ]
					then
							histogram_count=$histogram_line_count
							path=$image
					fi
                fi
        esac
    done
    echo $path
}

case $1 in
	-h|--help) # never done this before ༽つ۞﹏۞༼つ
		println=false; echo
		while read line; do
			case $line in 
				\#*DESCRIPTION*) println=true; echo ${line:1} ;;
				\#*) if $println; then echo ${line:1}; fi ;;
				*) break;
			esac;
		done < "$0"
		exit 0
esac

create_thumbnail=false
create_gif=false
create_resized_gif=false
gif_size=300
file=$1
out=$(dirname $0)

# parse args
while [[ $# > 1 ]]
do
	shift
	arg="$1"
	case $arg in
		--create-gif)
			create_gif=true
			;;
		--create-thumbnail)
			create_thumbnail=true
			;;
		--create-resized-gif=*)
			create_resized_gif=true
			gif_size="${arg#*=}"
			;;
		--out=*)
		  out="${arg#*=}"
		  ;;
		*) # invalid/unknown arg
	esac
done

case "$(uname -s)" in
  CYGWIN*) out=$(cygpath -a "$out")
esac

temp=$(mktemp -d)
unzip -q -o "$file" -d "$temp"

# read the desc.txt file
desc_txt="$temp/desc.txt"
first_line=`head -n 1 $desc_txt | dos2unix`
width=`echo $first_line | awk '{print $1}'` # unused
height=`echo $first_line | awk '{print $2}'` # unused
size=`echo "${width}x${height}"` # unused
fps=`echo $first_line | awk '{print $3}'`
folders=`awk '{print $4}' $desc_txt | dos2unix`
delay=`echo "scale=2; 100/${fps}" | bc` # unused # fps = 1/(delay in seconds) = 100/(delay ticks)

# get the list of images in the correct order
files=""
for folder in $folders
do
	files=$(find "$temp/$folder/" -type f \( -iname \*.png -o -iname \*.jpg -o -iname \*.jpeg \) | sort)
	images="$images $files"
done

if $create_thumbnail
then
	thumbnail=$(get_image_with_most_colors $images)
	extension="${thumbnail##*.}"
	cp "$thumbnail" "$out/frame.$extension"
fi

if $create_gif #|| $create_resized_gif
then
	convert -delay $delay -loop 0 $images "$out/animation.gif"
fi

if $create_resized_gif
then
	convert "$out/animation.gif" -resize ${gif_size}x -coalesce -layers optimize "$out/animation_${gif_size}w.gif"
	#if ! $create_gif; then rm "$out/animation.gif"; fi
fi

# clean up
rm -rf "$temp"