#!/bin/bash # Copyright 2013 The Chromium Authors. All rights reserved. # Use of this source code is governed by a BSD-style license that can be # found in the LICENSE file. # The optimization code is based on pngslim (http://goo.gl/a0XHg) # and executes a similar pipleline to optimize the png file size. # The steps that require pngoptimizercl/pngrewrite/deflopt are omitted, # but this runs all other processes, including: # 1) various color-dependent optimizations using optipng. # 2) optimize the number of huffman blocks. # 3) randomize the huffman table. # 4) Further optimize using optipng and advdef (zlib stream). # Due to the step 3), each run may produce slightly different results. # # Note(oshima): In my experiment, advdef didn't reduce much. I'm keeping it # for now as it does not take much time to run. readonly ALL_DIRS=" ash/resources chrome/android/java/res chrome/app/theme chrome/browser/resources chrome/renderer/resources content/public/android/java/res content/shell/resources remoting/resources ui/android/java/res ui/resources ui/chromeos/resources ui/webui/resources/images " # Files larger than this file size (in bytes) will # use the optimization parameters tailored for large files. LARGE_FILE_THRESHOLD=3000 # Constants used for optimization readonly DEFAULT_MIN_BLOCK_SIZE=128 readonly DEFAULT_LIMIT_BLOCKS=256 readonly DEFAULT_RANDOM_TRIALS=100 # Taken from the recommendation in the pngslim's readme.txt. readonly LARGE_MIN_BLOCK_SIZE=1 readonly LARGE_LIMIT_BLOCKS=2 readonly LARGE_RANDOM_TRIALS=1 # Global variables for stats TOTAL_OLD_BYTES=0 TOTAL_NEW_BYTES=0 TOTAL_FILE=0 CORRUPTED_FILE=0 PROCESSED_FILE=0 declare -a THROBBER_STR=('-' '\\' '|' '/') THROBBER_COUNT=0 VERBOSE=false # Echo only if verbose option is set. function info { if $VERBOSE ; then echo $@ fi } # Show throbber character at current cursor position. function throbber { info -ne "${THROBBER_STR[$THROBBER_COUNT]}\b" let THROBBER_COUNT=$THROBBER_COUNT+1 let THROBBER_COUNT=$THROBBER_COUNT%4 } # Usage: pngout_loop ... # Optimize the png file using pngout with the given options # using various block split thresholds and filter types. function pngout_loop { local file=$1 shift local opts=$* if [ $OPTIMIZE_LEVEL == 1 ]; then for j in $(eval echo {0..5}); do throbber pngout -q -k1 -s1 -f$j $opts $file done else for i in 0 128 256 512; do for j in $(eval echo {0..5}); do throbber pngout -q -k1 -s1 -b$i -f$j $opts $file done done fi } # Usage: get_color_depth_list # Returns the list of color depth options for current optimization level. function get_color_depth_list { if [ $OPTIMIZE_LEVEL == 1 ]; then echo "-d0" else echo "-d1 -d2 -d4 -d8" fi } # Usage: process_grayscale # Optimize grayscale images for all color bit depths. # # TODO(oshima): Experiment with -d0 w/o -c0. function process_grayscale { info -ne "\b\b\b\b\b\b\b\bgray...." for opt in $(get_color_depth_list); do pngout_loop $file -c0 $opt done } # Usage: process_grayscale_alpha # Optimize grayscale images with alpha for all color bit depths. function process_grayscale_alpha { info -ne "\b\b\b\b\b\b\b\bgray-a.." pngout_loop $file -c4 for opt in $(get_color_depth_list); do pngout_loop $file -c3 $opt done } # Usage: process_rgb # Optimize rgb images with or without alpha for all color bit depths. function process_rgb { info -ne "\b\b\b\b\b\b\b\brgb....." for opt in $(get_color_depth_list); do pngout_loop $file -c3 $opt done pngout_loop $file -c2 pngout_loop $file -c6 } # Usage: huffman_blocks # Optimize the huffman blocks. function huffman_blocks { info -ne "\b\b\b\b\b\b\b\bhuffman." local file=$1 local size=$(stat -c%s $file) local min_block_size=$DEFAULT_MIN_BLOCK_SIZE local limit_blocks=$DEFAULT_LIMIT_BLOCKS if [ $size -gt $LARGE_FILE_THRESHOLD ]; then min_block_size=$LARGE_MIN_BLOCK_SIZE limit_blocks=$LARGE_LIMIT_BLOCKS fi let max_blocks=$size/$min_block_size if [ $max_blocks -gt $limit_blocks ]; then max_blocks=$limit_blocks fi for i in $(eval echo {2..$max_blocks}); do throbber pngout -q -k1 -ks -s1 -n$i $file done } # Usage: random_huffman_table_trial # Try compressing by randomizing the initial huffman table. # # TODO(oshima): Try adjusting different parameters for large files to # reduce runtime. function random_huffman_table_trial { info -ne "\b\b\b\b\b\b\b\brandom.." local file=$1 local old_size=$(stat -c%s $file) local trials_count=$DEFAULT_RANDOM_TRIALS if [ $old_size -gt $LARGE_FILE_THRESHOLD ]; then trials_count=$LARGE_RANDOM_TRIALS fi for i in $(eval echo {1..$trials_count}); do throbber pngout -q -k1 -ks -s0 -r $file done local new_size=$(stat -c%s $file) if [ $new_size -lt $old_size ]; then random_huffman_table_trial $file fi } # Usage: final_comprssion # Further compress using optipng and advdef. # TODO(oshima): Experiment with 256. function final_compression { info -ne "\b\b\b\b\b\b\b\bfinal..." local file=$1 if [ $OPTIMIZE_LEVEL == 2 ]; then for i in 32k 16k 8k 4k 2k 1k 512; do throbber optipng -q -nb -nc -zw$i -zc1-9 -zm1-9 -zs0-3 -f0-5 $file done fi for i in $(eval echo {1..4}); do throbber advdef -q -z -$i $file done # Clear the current line. if $VERBOSE ; then printf "\033[0G\033[K" fi } # Usage: get_color_type # Returns the color type name of the png file. Here is the list of names # for each color type codes. # 0: grayscale # 2: RGB # 3: colormap # 4: gray+alpha # 6: RGBA # See http://en.wikipedia.org/wiki/Portable_Network_Graphics#Color_depth # for details about the color type code. function get_color_type { local file=$1 echo $(file $file | awk -F, '{print $3}' | awk '{print $2}') } # Usage: optimize_size # Performs png file optimization. function optimize_size { # Print filename, trimmed to ensure it + status don't take more than 1 line local filename_length=${#file} local -i allowed_length=$COLUMNS-11 local -i trimmed_length=$filename_length-$COLUMNS+14 if [ "$filename_length" -lt "$allowed_length" ]; then info -n "$file|........" else info -n "...${file:$trimmed_length}|........" fi local file=$1 advdef -q -z -4 $file pngout -q -s4 -c0 -force $file $file.tmp.png if [ -f $file.tmp.png ]; then rm $file.tmp.png process_grayscale $file process_grayscale_alpha $file else pngout -q -s4 -c4 -force $file $file.tmp.png if [ -f $file.tmp.png ]; then rm $file.tmp.png process_grayscale_alpha $file else process_rgb $file fi fi info -ne "\b\b\b\b\b\b\b\bfilter.." local old_color_type=$(get_color_type $file) optipng -q -zc9 -zm8 -zs0-3 -f0-5 -out $file.tmp.png $file local new_color_type=$(get_color_type $file.tmp.png) # optipng may corrupt a png file when reducing the color type # to grayscale/grayscale+alpha. Just skip such cases until # the bug is fixed. See crbug.com/174505, crbug.com/174084. # The issue is reported in # https://sourceforge.net/tracker/?func=detail&aid=3603630&group_id=151404&atid=780913 if [[ $old_color_type == "RGBA" && $new_color_type == gray* ]] ; then rm $file.tmp.png else mv $file.tmp.png $file fi pngout -q -k1 -s1 $file huffman_blocks $file # TODO(oshima): Experiment with strategy 1. info -ne "\b\b\b\b\b\b\b\bstrategy" if [ $OPTIMIZE_LEVEL == 2 ]; then for i in 3 2 0; do pngout -q -k1 -ks -s$i $file done else pngout -q -k1 -ks -s1 $file fi if [ $OPTIMIZE_LEVEL == 2 ]; then random_huffman_table_trial $file fi final_compression $file } # Usage: process_file function process_file { local file=$1 local name=$(basename $file) # -rem alla removes all ancillary chunks except for tRNS pngcrush -d $TMP_DIR -brute -reduce -rem alla $file > /dev/null 2>&1 if [ -f $TMP_DIR/$name -a $OPTIMIZE_LEVEL != 0 ]; then optimize_size $TMP_DIR/$name fi } # Usage: optimize_file function optimize_file { local file=$1 if $using_cygwin ; then file=$(cygpath -w $file) fi local name=$(basename $file) local old=$(stat -c%s $file) local tmp_file=$TMP_DIR/$name let TOTAL_FILE+=1 process_file $file if [ ! -e $tmp_file ] ; then let CORRUPTED_FILE+=1 echo "$file may be corrupted; skipping\n" return fi local new=$(stat -c%s $tmp_file) let diff=$old-$new let percent=$diff*100 let percent=$percent/$old if [ $new -lt $old ]; then info "$file: $old => $new ($diff bytes: $percent%)" cp "$tmp_file" "$file" let TOTAL_OLD_BYTES+=$old let TOTAL_NEW_BYTES+=$new let PROCESSED_FILE+=1 else if [ $OPTIMIZE_LEVEL == 0 ]; then info "$file: Skipped" else info "$file: Unable to reduce size" fi rm $tmp_file fi } function optimize_dir { local dir=$1 if $using_cygwin ; then dir=$(cygpath -w $dir) fi for f in $(find $dir -name "*.png"); do optimize_file $f done } function install_if_not_installed { local program=$1 local package=$2 which $program > /dev/null 2>&1 if [ "$?" != "0" ]; then if $using_cygwin ; then echo "Couldn't find $program. " \ "Please run cygwin's setup.exe and install the $package package." exit 1 else read -p "Couldn't find $program. Do you want to install? (y/n)" [ "$REPLY" == "y" ] && sudo apt-get install $package [ "$REPLY" == "y" ] || exit fi fi } function fail_if_not_installed { local program=$1 local url=$2 which $program > /dev/null 2>&1 if [ $? != 0 ]; then echo "Couldn't find $program. Please download and install it from $url ." exit 1 fi } # Check pngcrush version and exit if the version is in bad range. # See crbug.com/404893. function exit_if_bad_pngcrush_version { local version=$(pngcrush -v 2>&1 | awk "/pngcrush 1.7./ {print \$3}") local version_num=$(echo $version | sed "s/\.//g") if [[ (1748 -lt $version_num && $version_num -lt 1773) ]] ; then echo "Your pngcrush ($version) has a bug that exists from " \ "1.7.49 to 1.7.72 (see crbug.com/404893 for details)." echo "Please upgrade pngcrush and try again" exit 1; fi } function show_help { local program=$(basename $0) echo \ "Usage: $program [options] ... $program is a utility to reduce the size of png files by removing unnecessary chunks and compressing the image. Options: -o Specify optimization level: (default is 1) 0 Just run pngcrush. It removes unnecessary chunks and perform basic optimization on the encoded data. 1 Optimize png files using pngout/optipng and advdef. This can further reduce addtional 5~30%. This is the default level. 2 Aggressively optimize the size of png files. This may produce addtional 1%~5% reduction. Warning: this is *VERY* slow and can take hours to process all files. -c Same as -r but referencing a git commit. Only files changed between this commit and HEAD will be processed. -v Shows optimization process for each file. -h Print this help text." exit 1 } if [ "$(expr substr $(uname -s) 1 6)" == "CYGWIN" ]; then using_cygwin=true else using_cygwin=false fi # The -i in the shebang line should result in $COLUMNS being set on newer # versions of bash. If it's not set yet, attempt to set it. if [ -z $COLUMNS ]; then which tput > /dev/null 2>&1 if [ "$?" == "0" ]; then COLUMNS=$(tput cols) else # No tput either... give up and just guess 80 columns. COLUMNS=80 fi export COLUMNS fi OPTIMIZE_LEVEL=1 # Parse options while getopts o:c:h:v opts do case $opts in c) COMMIT=$OPTARG ;; o) if [[ "$OPTARG" != 0 && "$OPTARG" != 1 && "$OPTARG" != 2 ]] ; then show_help fi OPTIMIZE_LEVEL=$OPTARG ;; v) VERBOSE=true ;; [h?]) show_help;; esac done # Remove options from argument list. shift $(($OPTIND -1)) # Make sure we have all necessary commands installed. install_if_not_installed pngcrush pngcrush exit_if_bad_pngcrush_version if [ $OPTIMIZE_LEVEL -ge 1 ]; then install_if_not_installed optipng optipng if $using_cygwin ; then fail_if_not_installed advdef "http://advancemame.sourceforge.net/comp-readme.html" else install_if_not_installed advdef advancecomp fi if $using_cygwin ; then pngout_url="http://www.advsys.net/ken/utils.htm" else pngout_url="http://www.jonof.id.au/kenutils" fi fail_if_not_installed pngout $pngout_url fi # Create tmp directory for crushed png file. TMP_DIR=$(mktemp -d) if $using_cygwin ; then TMP_DIR=$(cygpath -w $TMP_DIR) fi # Make sure we cleanup temp dir #trap "rm -rf $TMP_DIR" EXIT # If no directories are specified, optimize all directories. DIRS=$@ set ${DIRS:=$ALL_DIRS} info "Optimize level=$OPTIMIZE_LEVEL" if [ -n "$COMMIT" ] ; then # To keep git logic below sane, require it be run from the top dir. if [ ! -e ../.gclient ]; then echo "$0 must be run in src directory" exit 1 fi ALL_FILES=$(git diff --name-only $COMMIT HEAD $DIRS | grep "png$") ALL_FILES_LIST=( $ALL_FILES ) echo "Processing ${#ALL_FILES_LIST[*]} files" for f in $ALL_FILES; do if [ -f $f ] ; then optimize_file $f else echo "Skipping deleted file: $f"; fi done else for d in $DIRS; do if [ -d $d ] ; then info "Optimizing png files in $d" optimize_dir $d info "" elif [ -f $d ] ; then optimize_file $d else echo "Not a file or directory: $d"; fi done fi # Print the results. echo "Optimized $PROCESSED_FILE/$TOTAL_FILE files in" \ "$(date -d "0 + $SECONDS sec" +%Ts)" if [ $PROCESSED_FILE != 0 ]; then let diff=$TOTAL_OLD_BYTES-$TOTAL_NEW_BYTES let percent=$diff*100/$TOTAL_OLD_BYTES echo "Result: $TOTAL_OLD_BYTES => $TOTAL_NEW_BYTES bytes" \ "($diff bytes: $percent%)" fi if [ $CORRUPTED_FILE != 0 ]; then echo "Warning: corrupted files found: $CORRUPTED_FILE" echo "Please contact the author of the CL that landed corrupted png files" fi