[PATCH] Support "image/png; mode=8bit" imagery

[nkamapper]

I believe JOSM is not supporting 8 bit palette PNG at the moment.

It turned up as a problem when trying to use the WMTS service of Oslo municipality, where only one of eight layers are usable in JOSM: ​https://od2.pbe.oslo.kommune.no/mapcache/wmts?service=wmts&request=getcapabilities

[taylor.smock]

This is a fairly simple patch.

src/org/openstreetmap/josm/data/imagery/WMTSTileSource.java

@@ -549 +549 @@
         List<String> supportedMimeTypes = new ArrayList<>(Arrays.asList(ImageIO.getReaderMIMETypes()));
         supportedMimeTypes.add("image/jpgpng");         // used by ESRI
         supportedMimeTypes.add("image/png8");           // used by geoserver
+        supportedMimeTypes.add("image/png; mode=8bit"); // used by MapServer
         if (supportedMimeTypes.contains("image/jpeg")) {
             supportedMimeTypes.add("image/jpg"); // sometimes misspelled by Arcgis
         }
@@ -606 +607 @@
         }
         if (layer.format == null) {
             // no format found - it's mandatory parameter - can't use this layer
-            Logging.warn(tr("Can''t use layer {0} because no supported formats where found. Layer is available in formats: {1}",
+            Logging.warn(tr("Can''t use layer {0} because no supported formats were found. Layer is available in formats: {1}",
                     layer.getUserTitle(),
                     String.join(", ", unsupportedFormats)));
             return null;
         }
+        // Java has issues if spaces are not URL encoded. Ensure that we URL encode the spaces.
+        if (layer.format.contains(" ")) {
+            layer.format = layer.format.replace(" ", "&20");
+        }
         return layer;
     }
 

[taylor.smock]

In 18567/josm:

Fix #22391: Support "image/png; mode=8bit" imagery

[stoecker]

Ähm. URL encoded is %20, not &20!

[taylor.smock]

That is funny. I wonder why &20 worked when I tested it. I would have expected the server to not return data.

[taylor.smock]

In 18568/josm:

See #22391/r18567: fix typo (&20 -> %20 for ' ' url encoding)

[taylor.smock]

In 22.09 hotfix.