Only Aspect ratio is used while setting the output configuration using setOutputConfiguration of VideoOutputSettingsProxy
Output configuration is set for Video output port using setOutputConfiguration API of DeviceSettingsVideoOutputPortImpl class. This class inturn calls setOutputConfiguration of VideoOutputSettingsProxy class.
In this method updateHScreenAspectRatio method is called which updates all the three devices (Graphics, Back ground, Video).
This API takes current HScreen and requested config aspect ratio as input parameters.
For updating the config this aspect ratio is used along with the current grahics device resolution.
As a result coherent configuration selected will have the requested aspect ratio and the resolution of the current graphics device instead of resolution requested.
Should not we be using the resolution also, so that the coherent configuration that is applied will be as near as possible to the requested configuration