Image Requests

In general, image requests are GET requests and are identified by the value image for the parameter type. Except for error cases, responses to image requests will always contain image data. The resulting image format depends on the renderer addressed. The renderer also defines the specific image-renderer used and the optionally applied image effects.

The image request is evaluated and depending on the renderer settings, the request is passed on to the image-renderer which assembles the image from the data stored in the internal storage or the multiresolution files. If any effects are specified in the renderer or in the request parameters they will then be applied before the image is finally converted and compressed to the format defined in the renderer. A typical image request therefore has the following parameters:

 

ParameterDescriptionDefault
Type
Mandatory parameter specifying the request type-
Renderer
Specifies the renderer to be used.Defined in server configuration
Source
Mandatory, specifies the image requested-
Effects
Optional effects to apply to the resulting image-
Quality
Optional parameter used to define the compression quality when requesting a jpg imageDefined in the renderer


Depending on the image-renderer used there can be more mandatory or optional parameters.