diff --git a/process_assets b/process_assets
index 1e02512..78cec90 100755
--- a/process_assets
+++ b/process_assets
@@ -26,9 +26,15 @@ function processImage {
 	$inkscape -d 120 -e $2/res/drawable-ldpi/${file/.svg}.png $1 >& /dev/null
 }
 
+timestamp="201002211200.00"
+
+tempfile=mktemp
+trap "rm -f $tempfile" SIGINT SIGTERM
+touch -t $timestamp $tempfile
+
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
-for f in $(find $1 -name *.svg -type f);
+for f in $(find $1 -name *.svg -type f -newer $tempfile);
 do
 	if [[ "$f" == *.9.svg* ]]; then
 		$DIR/gen9patch.py $f $2
@@ -36,3 +42,5 @@ do
 		processImage $f $2
 	fi
 done
+
+rm -f $tempfile