+ local token
+ token=$(echo "${1}" | grep -e "^dup" | ${SED} "s/^dup[0-9]\+-\([0-9]\+\).*/\1/g")
+ echo "${token}"
+}
+
+# Generate frame index name with leading zeroes:
+# Arg1: frame number
+function get_frame_name()
+{
+ local index
+
+ index=$(printf "${F_FMT}" ${1})
+ echo "${dest}/${dest}-${group}-f${index}.png"
+}
+
+# Arg1: start frame
+# Arg1: end frame
+function insert_empty_frames()
+{
+ local w
+ local start
+ local end
+ local wfname
+
+ start=${1}
+ end=${2}
+
+ for w in $(seq ${start} ${end}); do
+ log_dbg "New frame ID: ${w} (empty)"
+
+ wfname=$(get_frame_name ${w})
+
+ cp ${dest}/background.png ${wfname}
+ done
+}
+
+function record_max_nf()
+{
+ if [ ${nf} -gt ${max_nf} ]; then
+ max_nf="${nf}"
+ fi