--- src/jpeg2hdrgen.orig	Wed Aug 23 07:25:58 2006
+++ src/jpeg2hdrgen	Thu Jun 21 14:34:33 2007
@@ -28,18 +28,25 @@
 export LC_ALL
 
 
-JHEAD="jhead"                   # program for extracting exif info from jpegs
-
-TEST_JHEAD=`which jhead`;
-if [ "$TEST_JHEAD" = "" ]; then
-    echo "Program 'jhead' is required to run this script."
-    echo "Install appropriate software, for example from:"
-    echo "http://www.sentex.net/~mwandel/jhead/"
+JHEAD='jhead'                   # program for extracting exif info from jpegs
+EXIF='exif'                     # another one
+EXIV2='exiv2'                   # and one more
+
+CMD=`which ${JHEAD}`
+[ -n "${CMD}" ] || CMD=`which ${EXIF}`
+[ -n "${CMD}" ] || CMD=`which ${EXIV2}`
+if [ -z "${CMD}" ]
+then
+    cat <<MSG
+One of the following commands are required to run this script:
+ '${JHEAD}' - stand-alone program (http://www.sentex.net/~mwandel/jhead/)
+ '${EXIF}'  - part of libexif project (http://sf.net/projects/libexif/)
+ '${EXIV2}' - part of exiv2 project (http://www.exiv2.org/)
+MSG
     exit 1;
 fi
 
-#Note: Double backslash MUST be put in front of each $ sign
-AWK_PROGRAM=`cat <<EOF
+AWK_PROGRAM='
 BEGIN {
   exposure="";
   aperture="";
@@ -58,23 +65,49 @@
     print exposure " " aperture " " iso_speed " 0";
 }
 
+## jhead output
 /^Exposure time: ([0-9]*\.[0-9]) */ {
-  exposure = 1/\\$3;
+  exposure = 1/$3;
 }
-
 /^Aperture *: f\/([0-9]*\.[0-9]*)/ {
-  aperture = substr(\\$3,3);
+  aperture = substr($3,3);
 }
-
 /^ISO equiv. *: ([0-9]*\.?[0-9]*)/ {
-  iso_speed = \\$4;
+  iso_speed = $4;
 }
 
-EOF`
+## exif output
+/^Exposure Time *\|.+ sec\./ {
+  if (split(substr($3,2),a,"/") == 2)
+    exposure = a[2];
+  else
+    exposure = 1/a[1];
+}
+/^FNumber *\|f\/.+/ {
+    aperture = substr($2,4);
+}
+/^ISO Speed Ratings *\|.+/ {
+    iso_speed = substr($4,2);
+}
 
-while [ "$1" != "" ]; do
-    EXPOSURE_INFO=`$JHEAD $1 | awk "$AWK_PROGRAM"`
-    echo $1 $EXPOSURE_INFO
+## exiv2 output
+/^Exposure time *: .+ s/ {
+  if (split($4,a,"/") == 2)
+    exposure = a[2];
+  else
+    exposure = 1/a[1];
+}
+/^Aperture *: F.+/ {
+    aperture = substr($3,2);
+}
+/^ISO speed *: .+/ {
+    iso_speed = $4;
+}
+'
 
+while [ ${#} -ne 0 ]
+do
+    printf "${1} "
+    ${CMD} "${1}" | awk "${AWK_PROGRAM}"
     shift
 done