Added 2 Band blending
Added 2 Band blending

This can be used to initialize or for the final last round. It preserves high frequency from the input with the highest alpha.

NeoGeographyToolkit/StereoPipeline,njwilson23/StereoPipeline,oleg-alexandrov/StereoPipeline,NeoGeographyToolkit/StereoPipeline,oleg-alexandrov/StereoPipeline,aaronknister/StereoPipeline,aaronknister/StereoPipeline,njwilson23/StereoPipeline,DougFirErickson/StereoPipeline,ScottMcMichael/StereoPipeline,DougFirErickson/StereoPipeline,NeoGeographyToolkit/StereoPipeline,aaronknister/StereoPipeline,ScottMcMichael/StereoPipeline,aaronknister/StereoPipeline,ScottMcMichael/StereoPipeline,oleg-alexandrov/StereoPipeline,ScottMcMichael/StereoPipeline,ScottMcMichael/StereoPipeline,DougFirErickson/StereoPipeline,njwilson23/StereoPipeline,aaronknister/StereoPipeline,ScottMcMichael/StereoPipeline,DougFirErickson/StereoPipeline,DougFirErickson/StereoPipeline,oleg-alexandrov/StereoPipeline,NeoGeographyToolkit/StereoPipeline,NeoGeographyToolkit/StereoPipeline,NeoGeographyToolkit/StereoPipeline,njwilson23/StereoPipeline,DougFirErickson/StereoPipeline,njwilson23/StereoPipeline,oleg-alexandrov/StereoPipeline,oleg-alexandrov/StereoPipeline,njwilson23/StereoPipeline