switch to pdf version 1.5 for pdf filtering

Author: thomasWeise

scripts/filterPdf.sh

@@ -8,7 +8,8 @@ set -o errtrace  # trace ERR through 'time command' and other functions
 set -o nounset   # set -u : exit the script if you try to use an uninitialized variable
 set -o errexit   # set -e : exit the script if any statement returns a non-true return value
 
-echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Welcome to the pdf filtering script."
+pdfVersion="1.5"
+echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Welcome to the pdf filtering script using pdf $pdfVersion compliance."
 
 currentDir="$(pwd)"
 echo "$(date +'%0Y-%0m-%0d %0R:%0S'): We are working in directory: '$currentDir'."
@@ -48,7 +49,7 @@ do
      -dCannotEmbedFontPolicy=/Error \
      -dColorConversionStrategy=/LeaveColorUnchanged \
      -dColorImageFilter=/FlateEncode \
-     -dCompatibilityLevel=1.4 \
+     -dCompatibilityLevel="$pdfVersion" \
      -dCompressFonts=true \
      -dCompressStreams=true \
      -dCreateJobTicket=false \