Recompress PNGs.

Recompress PNGs using the current versions of various compressors:

  optipng 0.7.6
  advpng 1.20
  advdef 1.20
  pngcrush 1.8.1

Parallelize PNG compression. Note why we're not using a couple of other
compression utilities.

Change-Id: I52757d0bc2d424013e7f00b693a0f5378427cc31
Reviewed-on: https://code.wireshark.org/review/16209
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Gerald Combs <gerald@wireshark.org>

1 files changed, 29 insertions, 7 deletions

diff --git a/tools/compress-pngs.sh b/tools/compress-pngs.sh
index ea93f3d753..c70456e569 100755
--- a/tools/compress-pngs.sh
+++ b/tools/compress-pngs.sh
@@ -28,10 +28,32 @@ if [ -n "$1" ] ; then
     FILE_LIST_CMD="echo $1"
 fi
 
-bash -c "$FILE_LIST_CMD" | while read PNG_FILE ; do
-    echo Compressing $PNG_FILE
-    hash optipng 2>/dev/null  && optipng -o3 -quiet "$PNG_FILE"
-    hash advpng 2>/dev/null   && advpng -z -4 "$PNG_FILE"
-    hash advdef 2>/dev/null   && advdef -z -4 "$PNG_FILE"
-    hash pngcrush 2>/dev/null && pngcrush -q -ow -brute "$PNG_FILE"
-done
+# Other utilities:
+# PNGOUT (http://advsys.net/ken/utils.htm). Closed source.
+# pngquant (https://pngquant.org/). Lossy.
+
+JOBS=8
+export FILE_LIST_CMD
+(
+    echo -n "PNG_FILES ="
+    bash -c "$FILE_LIST_CMD" | while read PNG_FILE ; do
+        echo -e " \\"
+        echo -e -n "\t${PNG_FILE}"
+
+    done
+    cat <<"FIN"
+
+
+all: $(PNG_FILES)
+
+$(PNG_FILES): FORCE
+	@echo Compressing $@
+	@hash optipng 2>/dev/null  && optipng -o3 -quiet "$@"
+	@hash advpng 2>/dev/null   && advpng -z -4 "$@"
+	@hash advdef 2>/dev/null   && advdef -z -4 "$@"
+	@hash pngcrush 2>/dev/null && pngcrush -q -ow -brute -reduce -noforce "$@" pngout.$$$$.png
+
+FORCE:
+FIN
+
+) | make -j $JOBS -f -