Use markdown metadata to provide GPS

GPS coordinates can be given in Lat,Lon fields
in the Markdown files.
These override the EXIF GPS coordinates, if
both are present.

AUTHORS

@@ -53,6 +53,7 @@ alphabetical order):
 - Sébastien Maccagnoni-Munch
 - Sean Grider (@kaibutsux)
 - Simon Conseil
+- @stasinos
 - Stefano Zacchiroli
 - @subwarpspeed
 - @t-animal

docs/image_information.rst

@@ -16,6 +16,10 @@ keys are used by Sigal to get the useful informations on the gallery:
 - *Title*: the image title.
 - *Date*: the file date, useful when it cannot be read from the EXIF metadata,
   e.g. for videos and some image formats.
+- *Lat* and *Lon*: geo-location for positioning the image on map galleries.
+  Note that this overrides EXIF coordinates, so except for localizing when
+  EXIF cooredinates are missing it can also be used to localize the image
+  based on what is depicted instead of where the camera was standing.
 
 Any additional meta-data is available in the templates. For instance::
 

src/sigal/gallery.py

@@ -5,6 +5,7 @@
 # Copyright (c) 2017      - Mate Lakat
 # Copyright (c) 2018      - Edwin Steele
 # Copyright (c) 2021      - Tim AtLee
+# Copyright (c) 2024      - Stasinos Konstantopoulos
 
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to
@@ -217,7 +218,7 @@ class Media:
 
     def _get_markdown_metadata(self):
         """Get metadata from filename.md."""
-        meta = {"title": "", "description": "", "meta": {}}
+        meta = {"title": "", "description": "", "lat": "", "lon": "", "meta": {}}
         if isfile(self.markdown_metadata_filepath):
             meta.update(read_markdown(self.markdown_metadata_filepath))
         return meta
@@ -286,6 +287,15 @@ class Image(Media):
 
         return meta
 
+    @cached_property
+    def lat(self):
+        return self.markdown_metadata.get("lat", {})
+
+    @cached_property
+    def lon(self):
+        """Other metadata extracted from the Markdown index.md file."""
+        return self.markdown_metadata.get("lon", {})
+
     @cached_property
     def raw_exif(self):
         """If not `None`, contains the raw EXIF tags."""

src/sigal/themes/default/templates/map.html

@@ -19,7 +19,15 @@
 
   var photos = [];
   {% for media in album.medias %}
-    {% if media.exif and media.exif.gps %}
+    {% if media.lat and media.lon %}
+    photos.push({
+      lat: {{ media.lat }},
+      lng: {{ media.lon }},
+      url: "{{ media.thumbnail }}",
+      caption: "{{ media.title }}",
+      thumbnail: "{{ media.thumbnail }}",
+    });
+    {% elif media.exif and media.exif.gps %}
     photos.push({
       lat: {{ media.exif.gps.lat }},
       lng: {{ media.exif.gps.lon }},

src/sigal/utils.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2011-2023 - Simon Conseil
+# Copyright (c) 2024 - Stasinos Konstantopoulos
 
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to
@@ -140,6 +141,14 @@ def read_markdown(filename):
             output["title"] = MD.Meta["title"][0]
         except KeyError:
             pass
+        try:
+            output["lat"] = MD.Meta["lat"][0]
+        except KeyError:
+            pass
+        try:
+            output["lon"] = MD.Meta["lon"][0]
+        except KeyError:
+            pass
 
     return output