cvScroll channel viewer scroll
cvScroll(fhandle, step)
cvScroll(hObject, step)
scrolls the viewer for the specified figure or parent figure of the
specified object. step is the size of the data shift in elements of the
data array (negative to scroll back)
cvScroll(..., nloop)
limits the number of updates to nloop iterations.
cvScroll(..., nloop, InLoopFcn, EndScrollFcn)
specifies up to two function handles
InLoopFcn will be called after each screen update
EndScrollFcn will be called when the scrolling is complete
Both functions take the form:
function fcn(fhandle, [])