Hi - this is much clearer but I'm still not quite sure about the meaning - or maybe it's the notation - of the shift. In your example, it looks like the "_3" part of the shift is what pads the 1s on the left with zeros but I don't see how the overlap w/average of the bottom row of 1s with the first row of 3s is specified by the "2" in the shift. I'm also unsure why this shift pads a column on the result.
I guess it would help to see what the "0 0 shift" case looks like - where the anchor point is before the arrays get combined. I suspect part of my difficulty is that "shift" has a certain meaning already in J and it looks like you mean something subtly different here, maybe even two different things, something like "shift-extend" (on the columns) and "shift-overlap-average-where-not-extended" (on the rows). I'm also assuming the shift is applied only to the 1s in your example, relative to the 3s. Regards, Devon On Wed, May 30, 2012 at 4:52 PM, Alexander Mikhailov <avm...@yahoo.com> wrote: > > > > The specific problem which I'm working on right now is stitching. Also known > as "making panoramas from several independent shots". I'm having a simplified > version of the problem - I control the environment where pictures are taken. > In my case the pictures are taken with a camera which images samples under an > optical system, and the camera shifts linearly between shots - but of course > I wouldn't mind a more general solution. > > I don't think it's very unusual task in the image processing area... and I > don't think, for example, that this is the only task which enlarges images - > making from two nice rectangles, for example, a convex octagon. > > Unfortunately, averaging is just a simple option... I'd like to be able to > "fade out" one image and "fade in" another along, say, a gaussian curve. But > let's not have this as a requirement know. > > My problems seems to me to be geometrical - making a combined array. It's not > about "merging" individual points per se. For example, let's have 3 4$1 and > then 5 6$3 and then "combine" them, overlaying the second array with shift 2 > _3 on top of the first with averaging... > > 1 1 1 1 3 3 3 3 3 3 0 0 0 1 1 1 1 > 1 1 1 1 "operation" 3 3 3 3 3 3 -> 0 0 0 1 1 1 1 > 1 1 1 1 3 3 3 3 3 3 3 3 3 2 2 2 1 > 3 3 3 3 3 3 3 3 3 3 3 3 0 > 3 3 3 3 3 3 3 3 3 3 3 3 0 > 3 3 3 3 3 3 0 > 3 3 3 3 3 3 0 > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm -- Devon McCormick, CFA ^me^ at acm. org is my preferred e-mail ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
