Update README.md

README.md

@@ -5,6 +5,7 @@ View images, with zoom and pan
 - Shows the image full screen 
 - Allows zooming and panning
 - Tap image to close viewer
+- Image source can be Mendix image, base64 encoded data URL or a local file on the device
 
 ## Image width / height
 Widget needs the image width/height. For images created in the backend, use CommunityCommons.GetImageDimensions. For images taken in the native app, use the TakePictureAdvanced JavaScript action, which returns the dimensions in the ImageMetaData object.
@@ -19,3 +20,10 @@ The intended use of this widget is to show it without any other content on the p
 
 It is possible to put other content, like a header or footer, on the page, these will overlay the image.
 
+### Data URL
+For base64 encoded image data, the data must have the data URL prefix, where `<ext>` is the image format, like jpg or png: 
+```
+data:image/<ext>;base64,<base64 data>
+```
+(Do not include the `< >` in the data.)
+