Topic: Sub pixel measurements?
I was thinking about the "sub-pixel displacement measurements". I am a bit confused about the term "sub-pixel" . Becasue in remote sensing of landcover this term is usually used to discribed about how much fraction of different landcovers is present in a pixel. This means that we have lets say 20% grass and 50% snow and 30%bare soil in a pixel or spatial resolution of satellite data.
Well I think this term (sub-pixel) is used in different context in the paper "Automatic and precise orthorectification, coregistration, and subpixel correlation of satellite images, Application to ground deformation measurements - IEEE vol 45, No., 6, June 2007." The precise interpretation (to my understanding) of the results is that "It can measure displacement that is smaller than the scale of measurements but it cannot give distribution of displacement for every pixel within the window used to get power spectrum of the spatial signal". Well, but on the other hand if we use window step size of ONE then the algorithm can calculate displacement in every pixel of the images.
I will be very grateful if some one help in the interpretation of the scale of resulting displacment field.