[Patch] Simplify ImageEntry#extractExif?

[simon04]

While looking into #13376, I stumbled over a possible simplification at ImageEntry#extractExif (relating to #12255):

src/org/openstreetmap/josm/gui/layer/geoimage/ImageEntry.java

@@ -523 +523 @@
             Main.debug(ex);
         }
 
-        // Time and date. We can have these cases:
-        // 1) GPS_TIME_STAMP not set -> date/time will be null
-        // 2) GPS_DATE_STAMP not set -> use EXIF date or set to default
-        // 3) GPS_TIME_STAMP and GPS_DATE_STAMP are set
-        int[] timeStampComps = dirGps.getIntArray(GpsDirectory.TAG_TIME_STAMP);
-        if (timeStampComps != null) {
-            int gpsHour = timeStampComps[0];
-            int gpsMin = timeStampComps[1];
-            int gpsSec = timeStampComps[2];
-            Calendar cal = new GregorianCalendar(TimeZone.getTimeZone("UTC"));
-
-            // We have the time. Next step is to check if the GPS date stamp is set.
-            // dirGps.getString() always succeeds, but the return value might be null.
-            String dateStampStr = dirGps.getString(GpsDirectory.TAG_DATE_STAMP);
-            if (dateStampStr != null && dateStampStr.matches("^\\d+:\\d+:\\d+$")) {
-                String[] dateStampComps = dateStampStr.split(":");
-                cal.set(Calendar.YEAR, Integer.parseInt(dateStampComps[0]));
-                cal.set(Calendar.MONTH, Integer.parseInt(dateStampComps[1]) - 1);
-                cal.set(Calendar.DAY_OF_MONTH, Integer.parseInt(dateStampComps[2]));
-            } else {
-                // No GPS date stamp in EXIF data. Copy it from EXIF time.
-                // Date is not set if EXIF time is not available.
-                if (hasExifTime()) {
-                    // Time not set yet, so we can copy everything, not just date.
-                    cal.setTime(getExifTime());
-                }
-            }
-
-            cal.set(Calendar.HOUR_OF_DAY, gpsHour);
-            cal.set(Calendar.MINUTE, gpsMin);
-            cal.set(Calendar.SECOND, gpsSec);
-
-            setExifGpsTime(cal.getTime());
-        }
+        setExifGpsTime(dirGps.getGpsDate());
     }
 }

Are there some aspects against this simplification?

[holgermappt]

One difference is that no GPS time is extracted if GPS_TIME_STAMP is set but GPS_DATE_STAMP is not. I think the photo_geotagging plugin used to look at the exifGpsTime to decide what photo to update. It now uses hasNewGpsData() instead, so it is not that important anymore to have an EXIF GPS time. I don't know if there are photos that have that combination. The current code will set a wrong GPS date if GPS_DATE_STAMP is not set, exifTime is one second before midnight and GPS_TIME_STAMP is one second after midnight. But at the time the code was written is was more important to have an exifGpsTime than to have it right.

The other difference is that the current code does not change exifGpsTime if it is not set in the EXIF data. That should be changed in the patch to align it with the other code in extractExif, i.e. call setExifGpsTime() only if dirGps.getGpsDate() is not null. There might be a case where exifGpsTime is set during GPX correlation and then extractExif() is called (e.g. in the photoadjust plugin property editor). In that case the exifGpsTime should not be set to null.

For me the simplification is fine with the mentioned modification (set only if not null).

[simon04]

In 11037/josm:

fix #13668 - Simplify ImageEntry#extractExif

[simon04]

Milestone renamed