[tracker-miners: 1/4] fix the GPSLatitudeRef GPSLongitudeRef extraction

[Sam Thursfield <sthursfield src gnome org>]

commit 5a0ada56559874019b37caf6ad1fbfea7631de84
Author: Viktor Gal <viktor gal maeth com>
Date:   Mon Feb 3 09:09:21 2020 +0100

    fix the GPSLatitudeRef GPSLongitudeRef extraction

 src/libtracker-extract/tracker-exif.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)
---
diff --git a/src/libtracker-extract/tracker-exif.c b/src/libtracker-extract/tracker-exif.c
index 2d753ba2d..e0838e11c 100644
--- a/src/libtracker-extract/tracker-exif.c
+++ b/src/libtracker-extract/tracker-exif.c
@@ -312,14 +312,12 @@ get_gps_coordinate (ExifData *exif,
                ExifByteOrder order;
                ExifRational degrees, minutes, seconds;
                gfloat f;
-               gchar ref;
 
                if (entry->size == 24) {
                        order = exif_data_get_byte_order (exif);
                        degrees = exif_get_rational (entry->data, order);
                        minutes = exif_get_rational (entry->data + 8, order);
                        seconds = exif_get_rational (entry->data + 16, order);
-                       ref = exif_get_short (refentry->data, order);
 
                        /* Avoid ridiculous values */
                        if (degrees.denominator == 0 ||
@@ -332,8 +330,11 @@ get_gps_coordinate (ExifData *exif,
                                (gdouble) minutes.numerator / (minutes.denominator * 60) +
                                (gdouble) seconds.numerator / (seconds.denominator * 60 * 60);
 
-                       if (ref == 'S' || ref == 'W') {
-                               f = -1 * f;
+                       if (refentry->format == EXIF_FORMAT_ASCII && (refentry->size == 2)) {
+                               // following Exif Version 2.2 specs
+                               if (refentry->data[0] == 'S' || refentry->data[0] == 'W') {
+                                       f = -1 * f;
+                               }
                        }
 
                        return g_strdup_printf ("%f", f);