1 #!/bin/bash 2 # Copyright 2013 The Chromium Authors. All rights reserved. 3 # Use of this source code is governed by a BSD-style license that can be 4 # found in the LICENSE file. 5 6 # The optimization code is based on pngslim (http://goo.gl/a0XHg) 7 # and executes a similar pipleline to optimize the png file size. 8 # The steps that require pngoptimizercl/pngrewrite/deflopt are omitted, 9 # but this runs all other processes, including: 10 # 1) various color-dependent optimizations using optipng. 11 # 2) optimize the number of huffman blocks. 12 # 3) randomize the huffman table. 13 # 4) Further optimize using optipng and advdef (zlib stream). 14 # Due to the step 3), each run may produce slightly different results. 15 # 16 # Note(oshima): In my experiment, advdef didn't reduce much. I'm keeping it 17 # for now as it does not take much time to run. 18 19 readonly ALL_DIRS=" 20 ash/resources 21 ui/resources 22 chrome/app/theme 23 chrome/browser/resources 24 chrome/renderer/resources 25 webkit/glue/resources 26 remoting/resources 27 remoting/webapp 28 " 29 30 # Files larger than this file size (in bytes) will 31 # use the optimization parameters tailored for large files. 32 LARGE_FILE_THRESHOLD=3000 33 34 # Constants used for optimization 35 readonly DEFAULT_MIN_BLOCK_SIZE=128 36 readonly DEFAULT_LIMIT_BLOCKS=256 37 readonly DEFAULT_RANDOM_TRIALS=100 38 # Taken from the recommendation in the pngslim's readme.txt. 39 readonly LARGE_MIN_BLOCK_SIZE=1 40 readonly LARGE_LIMIT_BLOCKS=2 41 readonly LARGE_RANDOM_TRIALS=1 42 43 # Global variables for stats 44 TOTAL_OLD_BYTES=0 45 TOTAL_NEW_BYTES=0 46 TOTAL_FILE=0 47 PROCESSED_FILE=0 48 49 declare -a THROBBER_STR=('-' '\\' '|' '/') 50 THROBBER_COUNT=0 51 52 # Show throbber character at current cursor position. 53 function throbber { 54 echo -ne "${THROBBER_STR[$THROBBER_COUNT]}\b" 55 let THROBBER_COUNT=($THROBBER_COUNT+1)%4 56 } 57 58 # Usage: pngout_loop <file> <png_out_options> ... 59 # Optimize the png file using pngout with the given options 60 # using various block split thresholds and filter types. 61 function pngout_loop { 62 local file=$1 63 shift 64 local opts=$* 65 if [ $OPTIMIZE_LEVEL == 1 ]; then 66 for j in $(seq 0 5); do 67 throbber 68 pngout -q -k1 -s1 -f$j $opts $file 69 done 70 else 71 for i in 0 128 256 512; do 72 for j in $(seq 0 5); do 73 throbber 74 pngout -q -k1 -s1 -b$i -f$j $opts $file 75 done 76 done 77 fi 78 } 79 80 # Usage: get_color_depth_list 81 # Returns the list of color depth options for current optimization level. 82 function get_color_depth_list { 83 if [ $OPTIMIZE_LEVEL == 1 ]; then 84 echo "-d0" 85 else 86 echo "-d1 -d2 -d4 -d8" 87 fi 88 } 89 90 # Usage: process_grayscale <file> 91 # Optimize grayscale images for all color bit depths. 92 # 93 # TODO(oshima): Experiment with -d0 w/o -c0. 94 function process_grayscale { 95 echo -n "|gray" 96 for opt in $(get_color_depth_list); do 97 pngout_loop $file -c0 $opt 98 done 99 } 100 101 # Usage: process_grayscale_alpha <file> 102 # Optimize grayscale images with alpha for all color bit depths. 103 function process_grayscale_alpha { 104 echo -n "|gray-a" 105 pngout_loop $file -c4 106 for opt in $(get_color_depth_list); do 107 pngout_loop $file -c3 $opt 108 done 109 } 110 111 # Usage: process_rgb <file> 112 # Optimize rgb images with or without alpha for all color bit depths. 113 function process_rgb { 114 echo -n "|rgb" 115 for opt in $(get_color_depth_list); do 116 pngout_loop $file -c3 $opt 117 done 118 pngout_loop $file -c2 119 pngout_loop $file -c6 120 } 121 122 # Usage: huffman_blocks <file> 123 # Optimize the huffman blocks. 124 function huffman_blocks { 125 local file=$1 126 echo -n "|huffman" 127 local size=$(stat -c%s $file) 128 local min_block_size=$DEFAULT_MIN_BLOCK_SIZE 129 local limit_blocks=$DEFAULT_LIMIT_BLOCKS 130 131 if [ $size -gt $LARGE_FILE_THRESHOLD ]; then 132 min_block_size=$LARGE_MIN_BLOCK_SIZE 133 limit_blocks=$LARGE_LIMIT_BLOCKS 134 fi 135 let max_blocks=$size/$min_block_size 136 if [ $max_blocks -gt $limit_blocks ]; then 137 max_blocks=$limit_blocks 138 fi 139 140 for i in $(seq 2 $max_blocks); do 141 throbber 142 pngout -q -k1 -ks -s1 -n$i $file 143 done 144 } 145 146 # Usage: random_huffman_table_trial <file> 147 # Try compressing by randomizing the initial huffman table. 148 # 149 # TODO(oshima): Try adjusting different parameters for large files to 150 # reduce runtime. 151 function random_huffman_table_trial { 152 echo -n "|random" 153 local file=$1 154 local old_size=$(stat -c%s $file) 155 local trials_count=$DEFAULT_RANDOM_TRIALS 156 157 if [ $old_size -gt $LARGE_FILE_THRESHOLD ]; then 158 trials_count=$LARGE_RANDOM_TRIALS 159 fi 160 for i in $(seq 1 $trials_count); do 161 throbber 162 pngout -q -k1 -ks -s0 -r $file 163 done 164 local new_size=$(stat -c%s $file) 165 if [ $new_size -lt $old_size ]; then 166 random_huffman_table_trial $file 167 fi 168 } 169 170 # Usage: final_comprssion <file> 171 # Further compress using optipng and advdef. 172 # TODO(oshima): Experiment with 256. 173 function final_compression { 174 echo -n "|final" 175 local file=$1 176 if [ $OPTIMIZE_LEVEL == 2 ]; then 177 for i in 32k 16k 8k 4k 2k 1k 512; do 178 throbber 179 optipng -q -nb -nc -zw$i -zc1-9 -zm1-9 -zs0-3 -f0-5 $file 180 done 181 fi 182 for i in $(seq 1 4); do 183 throbber 184 advdef -q -z -$i $file 185 done 186 echo -ne "\r" 187 } 188 189 # Usage: get_color_type <file> 190 # Returns the color type name of the png file. Here is the list of names 191 # for each color type codes. 192 # 0 : grayscale 193 # 2 : RGB 194 # 3 : colormap 195 # 4 : gray+alpha 196 # 6 : RGBA 197 # See http://en.wikipedia.org/wiki/Portable_Network_Graphics#Color_depth 198 # for details about the color type code. 199 function get_color_type { 200 local file=$1 201 echo $(file $file | awk -F, '{print $3}' | awk '{print $2}') 202 } 203 204 # Usage: optimize_size <file> 205 # Performs png file optimization. 206 function optimize_size { 207 tput el 208 local file=$1 209 echo -n "$file " 210 211 advdef -q -z -4 $file 212 213 pngout -q -s4 -c0 -force $file $file.tmp.png 214 if [ -f $file.tmp.png ]; then 215 rm $file.tmp.png 216 process_grayscale $file 217 process_grayscale_alpha $file 218 else 219 pngout -q -s4 -c4 -force $file $file.tmp.png 220 if [ -f $file.tmp.png ]; then 221 rm $file.tmp.png 222 process_grayscale_alpha $file 223 else 224 process_rgb $file 225 fi 226 fi 227 228 echo -n "|filter" 229 local old_color_type=$(get_color_type $file) 230 optipng -q -zc9 -zm8 -zs0-3 -f0-5 $file -out $file.tmp.png 231 local new_color_type=$(get_color_type $file.tmp.png) 232 # optipng may corrupt a png file when reducing the color type 233 # to grayscale/grayscale+alpha. Just skip such cases until 234 # the bug is fixed. See crbug.com/174505, crbug.com/174084. 235 # The issue is reported in 236 # https://sourceforge.net/tracker/?func=detail&aid=3603630&group_id=151404&atid=780913 237 if [[ $old_color_type == "RGBA" && $new_color_type =~ gray.* ]] ; then 238 rm $file.tmp.png 239 echo -n "[skip opting]" 240 else 241 mv $file.tmp.png $file 242 fi 243 pngout -q -k1 -s1 $file 244 245 huffman_blocks $file 246 247 # TODO(oshima): Experiment with strategy 1. 248 echo -n "|strategy" 249 if [ $OPTIMIZE_LEVEL == 2 ]; then 250 for i in 3 2 0; do 251 pngout -q -k1 -ks -s$i $file 252 done 253 else 254 pngout -q -k1 -ks -s1 $file 255 fi 256 257 if [ $OPTIMIZE_LEVEL == 2 ]; then 258 random_huffman_table_trial $file 259 fi 260 261 final_compression $file 262 } 263 264 # Usage: process_file <file> 265 function process_file { 266 local file=$1 267 local name=$(basename $file) 268 # -rem alla removes all ancillary chunks except for tRNS 269 pngcrush -d $TMP_DIR -brute -reduce -rem alla $file > /dev/null 270 271 if [ $OPTIMIZE_LEVEL != 0 ]; then 272 optimize_size $TMP_DIR/$name 273 fi 274 } 275 276 # Usage: optimize_file <file> 277 function optimize_file { 278 local file=$1 279 if $using_cygwin ; then 280 file=$(cygpath -w $file) 281 fi 282 283 local name=$(basename $file) 284 local old=$(stat -c%s $file) 285 local tmp_file=$TMP_DIR/$name 286 287 process_file $file 288 289 local new=$(stat -c%s $tmp_file) 290 let diff=$old-$new 291 let percent=($diff*100)/$old 292 let TOTAL_FILE+=1 293 294 tput el 295 if [ $new -lt $old ]; then 296 echo -ne "$file : $old => $new ($diff bytes : $percent %)\n" 297 mv "$tmp_file" "$file" 298 let TOTAL_OLD_BYTES+=$old 299 let TOTAL_NEW_BYTES+=$new 300 let PROCESSED_FILE+=1 301 else 302 if [ $OPTIMIZE_LEVEL == 0 ]; then 303 echo -ne "$file : skipped\r" 304 fi 305 rm $tmp_file 306 fi 307 } 308 309 function optimize_dir { 310 local dir=$1 311 if $using_cygwin ; then 312 dir=$(cygpath -w $dir) 313 fi 314 315 for f in $(find $dir -name "*.png"); do 316 optimize_file $f 317 done 318 } 319 320 function install_if_not_installed { 321 local program=$1 322 local package=$2 323 which $program > /dev/null 2>&1 324 if [ "$?" != "0" ]; then 325 if $using_cygwin ; then 326 echo "Couldn't find $program. " \ 327 "Please run cygwin's setup.exe and install the $package package." 328 exit 1 329 else 330 read -p "Couldn't find $program. Do you want to install? (y/n)" 331 [ "$REPLY" == "y" ] && sudo apt-get install $package 332 [ "$REPLY" == "y" ] || exit 333 fi 334 fi 335 } 336 337 function fail_if_not_installed { 338 local program=$1 339 local url=$2 340 which $program > /dev/null 2>&1 341 if [ $? != 0 ]; then 342 echo "Couldn't find $program. Please download and install it from $url ." 343 exit 1 344 fi 345 } 346 347 function show_help { 348 local program=$(basename $0) 349 echo \ 350 "Usage: $program [options] dir ... 351 352 $program is a utility to reduce the size of png files by removing 353 unnecessary chunks and compressing the image. 354 355 Options: 356 -o<optimize_level> Specify optimization level: (default is 1) 357 0 Just run pngcrush. It removes unnecessary chunks and perform basic 358 optimization on the encoded data. 359 1 Optimize png files using pngout/optipng and advdef. This can further 360 reduce addtional 5~30%. This is the default level. 361 2 Aggressively optimize the size of png files. This may produce 362 addtional 1%~5% reduction. Warning: this is *VERY* 363 slow and can take hours to process all files. 364 -r<revision> If this is specified, the script processes only png files 365 changed since this revision. The <dir> options will be used 366 to narrow down the files under specific directories. 367 -h Print this help text." 368 exit 1 369 } 370 371 if [ ! -e ../.gclient ]; then 372 echo "$0 must be run in src directory" 373 exit 1 374 fi 375 376 if [ "$(expr substr $(uname -s) 1 6)" == "CYGWIN" ]; then 377 using_cygwin=true 378 else 379 using_cygwin=false 380 fi 381 382 OPTIMIZE_LEVEL=1 383 # Parse options 384 while getopts o:r:h opts 385 do 386 case $opts in 387 r) 388 COMMIT=$(git svn find-rev r$OPTARG | tail -1) || exit 389 if [ -z "$COMMIT" ] ; then 390 echo "Revision $OPTARG not found" 391 show_help 392 fi 393 ;; 394 o) 395 if [[ ! "$OPTARG" =~ [012] ]] ; then 396 show_help 397 fi 398 OPTIMIZE_LEVEL=$OPTARG 399 ;; 400 [h?]) 401 show_help;; 402 esac 403 done 404 405 # Remove options from argument list. 406 shift $(($OPTIND -1)) 407 408 # Make sure we have all necessary commands installed. 409 install_if_not_installed pngcrush pngcrush 410 if [ $OPTIMIZE_LEVEL -ge 1 ]; then 411 install_if_not_installed optipng optipng 412 413 if $using_cygwin ; then 414 fail_if_not_installed advdef "http://advancemame.sourceforge.net/comp-readme.html" 415 else 416 install_if_not_installed advdef advancecomp 417 fi 418 419 if $using_cygwin ; then 420 pngout_url="http://www.advsys.net/ken/utils.htm" 421 else 422 pngout_url="http://www.jonof.id.au/kenutils" 423 fi 424 fail_if_not_installed pngout $pngout_url 425 fi 426 427 # Create tmp directory for crushed png file. 428 TMP_DIR=$(mktemp -d) 429 if $using_cygwin ; then 430 TMP_DIR=$(cygpath -w $TMP_DIR) 431 fi 432 433 # Make sure we cleanup temp dir 434 trap "rm -rf $TMP_DIR" EXIT 435 436 # If no directories are specified, optimize all directories. 437 DIRS=$@ 438 set ${DIRS:=$ALL_DIRS} 439 440 echo "Optimize level=$OPTIMIZE_LEVEL" 441 if [ -n "$COMMIT" ] ; then 442 ALL_FILES=$(git diff --name-only $COMMIT HEAD $DIRS | grep "png$") 443 ALL_FILES_LIST=( $ALL_FILES ) 444 echo "Processing ${#ALL_FILES_LIST[*]} files" 445 for f in $ALL_FILES; do 446 if [ -f $f ] ; then 447 optimize_file $f 448 else 449 echo "Skipping deleted file: $f"; 450 fi 451 done 452 else 453 for d in $DIRS; do 454 echo "Optimizing png files in $d" 455 optimize_dir $d 456 echo 457 done 458 fi 459 460 # Print the results. 461 if [ $PROCESSED_FILE == 0 ]; then 462 echo "Did not find any files (out of $TOTAL_FILE files)" \ 463 "that could be optimized" \ 464 "in $(date -u -d @$SECONDS +%T)s" 465 else 466 let diff=$TOTAL_OLD_BYTES-$TOTAL_NEW_BYTES 467 let percent=$diff*100/$TOTAL_OLD_BYTES 468 echo "Processed $PROCESSED_FILE files (out of $TOTAL_FILE files)" \ 469 "in $(date -u -d @$SECONDS +%T)s" 470 echo "Result : $TOTAL_OLD_BYTES => $TOTAL_NEW_BYTES bytes" \ 471 "($diff bytes : $percent %)" 472 fi 473
