diff --git a/piwik/indico_piwik/queries/graphs.py b/piwik/indico_piwik/queries/graphs.py
new file mode 100644
index 0000000..698cc53
--- /dev/null
+++ b/piwik/indico_piwik/queries/graphs.py
@@ -0,0 +1,49 @@
+from base64 import b64encode
+
+from . import PiwikQueryReportEventBase
+
+
+class PiwikQueryEventGraphBase(PiwikQueryReportEventBase):
+    """Base Piwik query for retrieving PNG graphs"""
+
+    def call(self, apiModule, apiAction, height=None, width=None, graphType='verticalBar', **query_params):
+        if height is not None:
+            query_params['height'] = height
+        if width is not None:
+            query_params['width'] = width
+        return super(PiwikQueryEventGraphBase, self).call(method='ImageGraph.get',
+                                                          apiModule=apiModule, apiAction=apiAction,
+                                                          aliasedGraph='1', graphType=graphType, **query_params)
+
+    def get_result(self):
+        """Perform the call and return the graph data
+
+        :return: Encoded PNG graph data string to be inserted in a `src`
+                 atribute of a HTML img tag.
+        """
+        img_prefix = 'data:image/png;base64,'
+        png = self.call(default_response='none')
+        if png == 'none':
+            return png
+        img_code = b64encode(png)
+        return img_prefix + img_code
+
+
+class PiwikQueryEventGraphVisits(PiwikQueryEventGraphBase):
+    def call(self, **query_params):
+        return super(PiwikQueryEventGraphVisits, self).call(apiModule='VisitsSummary', apiAction='get', width=720,
+                                                            height=260, graphType='evolution', **query_params)
+
+
+class PiwikQueryEventGraphDevices(PiwikQueryEventGraphBase):
+    def call(self, **query_params):
+        return super(PiwikQueryEventGraphDevices, self).call(apiModule='UserSettings', apiAction='getOS',
+                                                             period='range', width=320, height=260,
+                                                             graphType='horizontalBar', **query_params)
+
+
+class PiwikQueryEventGraphCountries(PiwikQueryEventGraphBase):
+    def call(self, **query_params):
+        return super(PiwikQueryEventGraphCountries, self).call(apiModule='UserCountry', apiAction='getCountry',
+                                                               period='range', width=490, height=260,
+                                                               graphType='horizontalBar', **query_params)