A method, comprising: receiving, by a sheet generator (103_1) and from a line buffer (101_1... 101_M), a line group of image data including multiple rows of data from a frame of image data, said multiple rows being sufficient in number to encompass multiple neighboring overlapping stencils; parsing, by the sheet generator (103_1), said line group into a plurality of smaller sized sheets (204, 205); and, for each sheet of the plurality of sheets: loading, by the sheet generator (103_1), said sheet (204, 205) into a stencil processor associated with the sheet generator and comprising a two dimensional shift array structure (306, 406, 602) coupled to an array (305, 405) of execution lanes (510, 601), the execution lane array (305,405) and the shift array structure (306, 406, 602) being fixed in position relative to one another; executing program code on said array (305, 405) of execution lanes (510, 601) to process said multiple neighboring overlapping stencils over said sheet (204, 205), wherein each execution lane (510, 601) processes its own stencil to generate an output value for that stencil, and wherein the output values of the execution lanes constitute respective pixel values in an output sheet of image data; and receiving, by the sheet generator (103_1), the output sheet of image data from the associated stencil processor (102_1). receiving, by a sheet generator (103_1) and from a line buffer (101_1... 101_M), a line group of image data including multiple rows of data from a frame of image data, said multiple rows being sufficient in number to encompass multiple neighboring overlapping stencils; parsing, by the sheet generator (103_1), said line group into a plurality of smaller sized sheets (204, 205); and, for each sheet of the plurality of sheets: loading, by the sheet generator (103_1), said sheet (204, 205) into a stencil processor associated with the sheet generator and comprising a two dimensional shift array structure (306, 406, 602) coupled to an array (305, 405) of execution lanes (510, 601), the execution lane array (305,405) and the shift array structure (306, 406, 602) being fixed in position relative to one another; executing program code on said array (305, 405) of execution lanes (510, 601) to process said multiple neighboring overlapping stencils over said sheet (204, 205), wherein each execution lane (510, 601) processes its own stencil to generate an output value for that stencil, and wherein the output values of the execution lanes constitute respective pixel values in an output sheet of image data; and receiving, by the sheet generator (103_1), the output sheet of image data from the associated stencil processor (102_1). loading, by the sheet generator (103_1), said sheet (204, 205) into a stencil processor associated with the sheet generator and comprising a two dimensional shift array structure (306, 406, 602) coupled to an array (305, 405) of execution lanes (510, 601), the execution lane array (305,405) and the shift array structure (306, 406, 602) being fixed in position relative to one another; executing program code on said array (305, 405) of execution lanes (510, 601) to process said multiple neighboring overlapping stencils over said sheet (204, 205), wherein each execution lane (510, 601) processes its own stencil to generate an output value for that stencil, and wherein the output values of the execution lanes constitute respective pixel values in an output sheet of image data; and receiving, by the sheet generator (103_1), the output sheet of image data from the associated stencil processor (102_1).