diff --git a/test/spec/ol/source/imagewmssource.test.js b/test/spec/ol/source/imagewmssource.test.js
index 06895b9684..18aa4848b8 100644
--- a/test/spec/ol/source/imagewmssource.test.js
+++ b/test/spec/ol/source/imagewmssource.test.js
@@ -3,7 +3,143 @@ goog.provide('ol.test.source.ImageWMS');
 
 describe('ol.source.ImageWMS', function() {
 
+  describe('#getImage', function() {
+
+    var extent, pixelRatio, options, projection, resolution;
+    beforeEach(function() {
+      extent = [10, 20, 30, 40];
+      pixelRatio = 1;
+      projection = ol.proj.get('EPSG:4326');
+      resolution = 0.1;
+      options = {
+        params: {
+          'LAYERS': 'layer'
+        },
+        ratio: 1,
+        url: 'http://example.com/wms'
+      };
+    });
+
+    it('returns the expected image URL', function() {
+      var source = new ol.source.ImageWMS(options);
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      expect(uri.getScheme()).to.be('http');
+      expect(uri.getDomain()).to.be('example.com');
+      expect(uri.getPath()).to.be('/wms');
+      var queryData = uri.getQueryData();
+      expect(queryData.get('BBOX')).to.be('20,10,40,30');
+      expect(queryData.get('CRS')).to.be('EPSG:4326');
+      expect(queryData.get('FORMAT')).to.be('image/png');
+      expect(queryData.get('HEIGHT')).to.be('200');
+      expect(queryData.get('LAYERS')).to.be('layer');
+      expect(queryData.get('REQUEST')).to.be('GetMap');
+      expect(queryData.get('SERVICE')).to.be('WMS');
+      expect(queryData.get('SRS')).to.be(undefined);
+      expect(queryData.get('STYLES')).to.be('');
+      expect(queryData.get('TRANSPARENT')).to.be('true');
+      expect(queryData.get('VERSION')).to.be('1.3.0');
+      expect(queryData.get('WIDTH')).to.be('200');
+      expect(uri.getFragment()).to.be.empty();
+    });
+
+    it('sets the SRS query value instead of CRS if version < 1.3', function() {
+      options.params.VERSION = '1.2';
+      var source = new ol.source.ImageWMS(options);
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('CRS')).to.be(undefined);
+      expect(queryData.get('SRS')).to.be('EPSG:4326');
+    });
+
+    it('allows various parameters to be overridden', function() {
+      options.params.FORMAT = 'image/jpeg';
+      options.params.TRANSPARENT = false;
+      var source = new ol.source.ImageWMS(options);
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('FORMAT')).to.be('image/jpeg');
+      expect(queryData.get('TRANSPARENT')).to.be('false');
+    });
+
+    it('does not add a STYLES= option if one is specified', function() {
+      options.params.STYLES = 'foo';
+      var source = new ol.source.ImageWMS(options);
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('STYLES')).to.be('foo');
+    });
+
+    it('changes the BBOX order for EN axis orientations', function() {
+      var source = new ol.source.ImageWMS(options);
+      projection = ol.proj.get('CRS:84');
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('BBOX')).to.be('10,20,30,40');
+    });
+
+    it('uses EN BBOX order if version < 1.3', function() {
+      options.params.VERSION = '1.1.0';
+      var source = new ol.source.ImageWMS(options);
+      var image =
+          source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('BBOX')).to.be('10,20,30,40');
+    });
+
+    it('sets MAP_RESOLUTION when the server is MapServer', function() {
+      options.serverType = ol.source.wms.ServerType.MAPSERVER;
+      var source = new ol.source.ImageWMS(options);
+      pixelRatio = 2;
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('MAP_RESOLUTION')).to.be('180');
+    });
+
+    it('sets FORMAT_OPTIONS when the server is GeoServer', function() {
+      options.serverType = ol.source.wms.ServerType.GEOSERVER;
+      var source = new ol.source.ImageWMS(options);
+      pixelRatio = 2;
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('FORMAT_OPTIONS')).to.be('dpi:180');
+    });
+
+    it('rounds FORMAT_OPTIONS to an integer when the server is GeoServer',
+       function() {
+         options.serverType = ol.source.wms.ServerType.GEOSERVER;
+         var source = new ol.source.ImageWMS(options);
+         pixelRatio = 1.325;
+         var image =
+             source.getImage(extent, resolution, pixelRatio, projection);
+         var uri = new goog.Uri(image.src_);
+         var queryData = uri.getQueryData();
+         expect(queryData.get('FORMAT_OPTIONS')).to.be('dpi:119');
+       });
+
+    it('sets DPI when the server is QGIS', function() {
+      options.serverType = ol.source.wms.ServerType.QGIS;
+      var source = new ol.source.ImageWMS(options);
+      pixelRatio = 2;
+      var image = source.getImage(extent, resolution, pixelRatio, projection);
+      var uri = new goog.Uri(image.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('DPI')).to.be('180');
+    });
+
+  });
+
 });
 
 
+goog.require('goog.Uri');
 goog.require('ol.source.ImageWMS');
+goog.require('ol.proj');
+goog.require('ol.source.wms.ServerType');