Abstract: In a hybrid multi-drop and multi-pass printing system, composite drops are formed from separate drops merging onto media and highlight regions are formed by using single drops to form a dot. Individual drops are nearly invisible and thus can form highlights with low graininess. As the density of the image increases, multi-drop dots are formed by merging two or more drops. Drops merging together on the media cover white space more efficiently, increase optical density without throughput loss and reduce ink ejection frequency. Multiple passes result in error hiding and improved ink/media interaction. An array of ink ejection elements forms a single printhead in a carriage which is passed along a scan axis perpendicular to the media in the advance direction so that the array path defines a swath area on the media surface. The ink ejection elements are energized during the initial passing step.

Abstract: A circuit for sharpening a pixel image includes M accumulators which provide a rolling sum for each of a sequence of image pixel values. Each rolling sum comprises the sum of pixel values in the accumulator, all pixel values resident in the M accumulators comprising an array of pixel values, with one such accumulator including a central array pixel value. M inputs apply a sequence of at least N image pixel values to each of the M accumulators. Each sequence of N image pixel values is logically arrayed along a first dimension of the image and each sequence changes as each new image pixel value is input and an oldest image pixel value is removed. Each time a new image pixel is input to an accumulator, the accumulator outputs a new rolling sum of the image pixel values present therein. An arithmetic circuit determines from each set of M rolling sums, an average pixel value of the array of image pixel values, and then derives a difference between the central image pixel value and the average image pixel value.

Abstract: A nonvolatile random access memory is formed by thin permalloy shaped into "wiggle" patterns and magnetized to establish a plurality of memory cells arranged into an array. Magnetic domain walls are formed at apexes of the "wiggle" pattern in each memory cell after a predetermined magnetic field is applied along the hard axis of the memory cell array by magnetization so aligned. Row address lines for reading and writing into the memory cells and column address lines for writing into the memory cells are provided to conduct currents through each column of the array for magnetoresistance readout.