WCS operations supported by GeoServer?

I have implemented a GeoTIFF image layer usinga WCS service in GeoServer 2.2.4. I have searched on the net for operations supported by WCS... it tells me about three operations:

GetCapabilities, DescribeCoverage and GetCoverage

I have used these operations using HTTP request and all are working perfectly.

My questions are:

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  is there any other way to use these operations other than HTTP request (if yes, please explain with some example)

  
  
  


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  does WCS support any other feature/facility/operation other than the above mentioned operations.

  
  

Is it possible to apply stretch operations (standard deviation/histogram etc) and other operations on GeoTIFF image in GeoServer using WCS?