Enhancement: exposure comp in preview's image info (issue 954)

rtengine/imagedata.cc

@@ -90,6 +90,7 @@ ImageData::ImageData (Glib::ustring fname, RawMetaDataLocation* ri) {
         make = "Unknown";
         model = "Unknown";
         orientation = "Unknown";
+        expcomp = 0;
         focal_len = 0;
         memset (&time, 0, sizeof(time));
     }
@@ -106,6 +107,7 @@ void ImageData::extractInfo () {
   model = "";
   serial = "";
   orientation = "";
+  expcomp = 0;
   shutter = 0;
   aperture = 0;
   focal_len = 0;
@@ -165,6 +167,8 @@ void ImageData::extractInfo () {
         aperture = exif->getTag ("ApertureValue")->toDouble ();
     if (exif->getTag ("FNumber"))
         aperture = exif->getTag ("FNumber")->toDouble ();
+    if (exif->getTag ("ExposureBiasValue"))
+        expcomp = exif->getTag ("ExposureBiasValue")->toDouble ();
     if (exif->getTag ("FocalLength"))
         focal_len = exif->getTag ("FocalLength")->toDouble ();
     if (exif->getTag ("ISOSpeedRatings"))
@@ -334,6 +338,17 @@ std::string ImageMetaData::shutterToString (double shutter) {
     return buffer;
 }
 
+std::string ImageMetaData::expcompToString (double expcomp) {
+
+    char buffer[256];
+    if (expcomp!=0.0){
+    	sprintf (buffer, "%0.1f", expcomp);
+    	return buffer;
+    }
+    else
+    	return "";
+}
+
 double ImageMetaData::shutterFromString (std::string s) {
 
     int i = s.find_first_of ('/');