saturday night fever is now commited

GravityField/encode.sh

@@ -12,14 +12,31 @@ SDIR="$1"
 FNAME="$2"
 echo "Encoding from " $SDIR " to " $FNAME
 
+#
+#  trying to guess the format of inoput files
+#
+firstfile=$(ls -1 $SDIR/* | head -1)
+echo "first file :" $firstfile
+filetype=$(file $firstfile | awk '{ print $2 }')
+echo "file type  :" $filetype
+
+case  $filetype in
+	PNG)		extension=".png"		;;
+	Netpbm)		extension=".pgm"		;;
+	*)		extension=".binary"		;;
+esac
+echo "extension  :" $extension
+
 TITLE='---{ experimental gravity field }---'
 
 ffmpeg  -nostdin					\
 	-loglevel warning				\
-	-y -r 30 -f image2 -i $SDIR/%05d.pgm 		\
+	-y -r 30 -f image2 -i ${SDIR}/%05d${extension}	\
 	-metadata artist='---{ tTh }---'		\
 	-metadata title="${TITLE}"			\
 	-c:v libx264 -pix_fmt yuv420p			\
 	$FNAME
 
+echo
+