SetImagingSettings requires all supported settings to be present

[simonameyertech]

I work for a ONVIF compatible VMS manufacturer and we are having issues using the SetImagingSettings with certain cameras.

According the wsdl file all children of the ImagingSettings20 element are optional. As there is no further restrictions specified in the specification this would suggest that we could send a request that just specifies the setting we wish to change and leaves out all other elements.

This would give an ImagingSettings20 that looks similar to:

<ns0:ImagingSettings>
    <ns1:Focus>
        <ns1:AutoFocusMode>AUTO</ns1:AutoFocusMode>
    </ns1:Focus>
</ns0:ImagingSettings>

where the namespaces are mapped on a higher level element.

However one camera manufacturer we are trying to work with is claiming that we must send all settings that the camera supports in any SetImagingSettings request. This would require an ImagingSettings20 element that looks like:

<ns0:ImagingSettings>
  <ns1:Brightness>50.0</ns1:Brightness>
  <ns1:ColorSaturation>65.0</ns2:ColorSaturation>
  <ns1:Contrast>65.0</ns3:Contrast>
  <ns1:Exposure>
    <ns1:Mode>AUTO</ns1:Mode>
    <ns1:Priority>FrameRate</ns1:Priority>
    <ns1:MinExposureTime>1.0</ns1:MinExposureTime>
    <ns1:MaxExposureTime>1000.0</ns1:MaxExposureTime>
    <ns1:MinGain>0.0</ns1:MinGain>
    <ns1:MaxGain>68.0</ns1:MaxGain>
  </ns1:Exposure>
  <ns1:Focus>
    <ns1:AutoFocusMode>AUTO</ns1:AutoFocusMode>
  </ns1:Focus>
  <ns1:IrCutFilter>AUTO</ns1:IrCutFilter>
  <ns1:Sharpness>50.0</ns1:Sharpness>
  <ns1:WideDynamicRange>
    <ns1:Mode>ON</ns1:Mode>
  </ns1:WideDynamicRange>
  <ns1:WhiteBalance>
    <ns1:Mode>AUTO</ns1:Mode>
  </ns1:WhiteBalance>
  <ns1:Extension>
    <ns1:ImageStabilization>
      <ns1:Mode>OFF</ns1:Mode>
      <ns1:Level>50</ns1:Level>
    </ns1:ImageStabilization>
    <ns1:Extension>
      <ns1:Extension>
        <ns1:ToneCompensation>
          <ns1:Mode>ON</ns1:Mode>
          <ns1:Level>0.5</ns1:Level>
        </ns1:ToneCompensation>
        <ns1:Defogging>
          <ns1:Mode>OFF</ns1:Mode>
          <ns1:Level>0.5</ns1:Level>
        </ns1:Defogging>
      </ns1:Extension>
    </ns1:Extension>
  </ns1:Extension>
</ns0:ImagingSettings>

This would require us to call GetImagingSettings each time before we can then call SetImagingSettings which for slow devices can be a significant slow down.

Having investigated further, this pattern of usage is the same as the device test client uses, but there is nothing that we can see in the specification that requires says that this is the expected or required usage pattern.

Is this something I have overlooked in the specification, if so where is it so I can avoid this mistake in the future? If it isn't then either the specification needs a clarification to specify what the correct usage pattern is or the device test specification needs tests adding that test setting a single property.

Thanks,
Simon Armstrong