Pixel image enhancement system and method

Claim 2

A computational method for converting a digitized source color image, containing at least three different colors contiguously disposed, into a second electronic color image of different effective spatial resolution, comprising: forming a scanned sequence of examination windows into said digitized color image, said examination windows being at least three pixels high and at least three pixels wide; defining a corresponding scanned sequence of elemental inferral areas smaller than, and substantially centered within, said examination windows; computing, in response to the pixels within the examination windows, at least one inferred-edge piece within at least some of said elemental inferral areas by separately computing unoriented inferred-edge pieces and separately computing an orientation to be applied to said unoriented inferred-edge prices; and combining the said inferred-edge pieces within at least one said elemental inferral-area, with color data from the source color image, to produce one elemental unit of said second electronic color image.

Claim 3

The method of claim 1 where said second electronic color image comprises a standard array of binary coded pixels.

Claim 4

The method of claim 1 where said second electronic color image is formatted for displaying on a color printer.

Claim 5

The method of claim 1 where said second electronic color image is formatted for display on a color display device.

Claim 6

The method of claim 4 where said color display device comprises a cathode ray tube.

Claim 7

The method of claim 4 where said color display device is a multiresolution display operated in a higher resolution mode than the resolution of the said digitized color image.

Claim 8

The method of claim 1 where combining inferred-edge pieces includes storage means for storing one previous scan line of computed elemental-inferral.

Claim 9

The method of claim 1 where said different effective spatial resolution is a decreased resolution.

Claim 10

The method of claim 1 where said different effective spatial resolution is an increased resolution.

Claim 11

The method of claim 1 where said examination window is rectangular and has an even number of pixels in one dimension and an odd number of pixels in the other dimension.

Claim 12

The method of claim 1 where said examination window is rectangular and has an even number of pixels in both dimensions.

Claim 13

The method of claim 1 where said examination window has variable size.

Claim 14

The method of claim 1 where said examination window is elliptical.

Claim 15

The method of claim 1 where said elemental inferral area is equal in area and aspect ratio to the input pixels in said digitized color image.

Claim 16

The method of claim 1 where said elemental inferral area at least partially overlaps two adjacent input pixels in said digitized color image.

Claim 17

The method of claim 1 where said elemental inferral area at least partially overlaps four touching input pixels in said digitized color image.

Claim 18

The method of claim 1 where said step of computing said inferred-edge pieces computes either zero, one, or two said inferred-edge pieces within a given said elemental inferral area.

Claim 19

The method of claim 1 where the step of computing comprises selecting from among a predefined set of no more than 1000 predefined inferred-edge pieces.

Claim 20

The method of claim 18 where said selection is represented as a binary case number.

Claim 21

The method of claim 18 where said selection is represented as an active signal on one among a set of conductors, said set of conductors corresponding to said set of predefined inferred-edge pieces.

Claim 22

The method of claim 1 where four possible orientations constitute all possible combinations of vertical and horizontal mirror imaging of unoriented edge pieces.

Claim 23

The method of claim 1 where eight possible orientations constitute all possible combinations of vertical and horizontal mirror imaging and 90 degree rotation of the unoriented inferred-edge pieces.

Claim 24

The method of claim 1 further including computing an intermediary map of existing edges in said digitized color image and within said examination window.

Claim 25

The method of claim 23 where said intermediary map of existing edges designates an edge as present between two contiguous source pixels when said contiguous source pixels differ at all in color.

Claim 26

The method of claim 24 where said two contiguous source pixels includes pair of pixels diagonally disposed with respect to each other and touching only at a shared corner.

Claim 27

The method of claim 23 where said intermediary map of existing edges designates an edge as present between two contiguous source pixels when said contiguous source pixels differ in color by more than a given threshold.

Claim 28

The method of claim 26 where said difference in color between contiguous pixels is computed as approximately representative of their psychological color difference.

Claim 29

The method of claim 26 where said given threshold is dynamically optimized.

Claim 30

The method of claim 23 where at least one scan line of said intermediary map of existing edges is buffered in lieu of buffering at least one scan line of said digitized color image.

Claim 31

The method of claim 1 where computing inferred-edge pieces includes detecting near-45 degrees edges in said digitized color image.

Claim 32

The method of claim 1 where computing inferred-edge pieces includes detecting single-pixel-width features in said digitized color image.

Claim 33

The method of claim 31 where detection of single-pixel-width features includes preserving said feature-width in the inferred image.

Claim 34

The method of claim 1 where said computation of an inferred edge requires that the source pixels along at least one side of that edge all have substantially the same color.

Claim 35

The method of claim 1 including estimating which of two diagonally disposed features is continuous through a given node where said continuity is otherwise ambiguous.

Claim 36

The method of claim 1 where the computation further includes knowing that the detection criteria for a given unoriented inferred-edge piece are internally symmetric and means for suppressing the generation of any orientation which is rendered redundant by said symmetry.

Claim 37

The method of claim 1 where said computation of said inferred-edge pieces includes detecting of curved edges which are tangent to orientation axes.

Claim 38

The method of claim 1 where said computation of inferred-edge pieces computes inferred-edge pieces which approximately join end-to-end with the inferred-edge pieces in adjacent elemental inferral areas.

Claim 39

The method of claim 1 where said computation of said inferred-edge pieces includes detecting double-size jags characteristic of sharply curved edges tangent to a 45 degree line.

Claim 40

The method of claim 1 where said computation of said inferred-edge pieces favors the longer inferred edge in otherwise ambiguous situations.

Claim 41

The method of claim 1 where a said inferred-edge piece comprises at least one straight-line segment represented as a vector.

Claim 42

The method of claim 40 whereas said vector or bitmap representation of said inferred-edge pieces is computed by accessing a lookup table.

Claim 43

The method of claim 1 where a said inferred-edge pieces are represented as an uncolored, bivalued bitmap of greater resolution than the digitized source color image.

Claim 44

The method of claim 42 where said bitmap is generated in run-length encoded form.

Claim 45

The method of claim 42 where said vector or bit map representation of said inferral-edge pieces is computed by accessing a lookup table.

Claim 46

The method of claim 1 where said elemental unit of said second electronic color image is a pulse of modulated width and position.

Claim 47

The method of claim 45 where said pulse is also modulated in amplitude.

Claim 48

The method of claim 1 where said elemental unit of said second electronic color image is a standard red-green-blue binary-encoded pixel.

Claim 49

The method of claim 47 further including utilizing the predefined separate locations of the individual primary color subpixels in a fixed-pixel color display for increasing effective luminance resolution.

Claim 50

The method of claim 1 where said elemental unit of said second electronic color image is a standard cyan-magenta-yellow-black binary-encoded pixel.

Claim 51

The method of claim 1 where said color display device comprises a fixed-pixel flat-panel display.

Claim 52

A computational method for converting a digitized source color image, containing at least three different colors contiguously disposed, into a second electronic color image of different effective spatial resolution, comprising: forming a scanned sequence of examination windows into said digitized color image, said examination windows being at least three pixels high and at least three pixels wide; defining a corresponding scanned sequence of elemental inferral areas smaller than, and substantially centered within, said examination windows; computing, in response to the pixels within the examination windows, at least one inferred-edge piece within at least some of said elemental inferral areas, said computing comprising selecting from among a predefined set of inferred-edge pieces, said selecting comprising detecting major subfeatures shared by a plurality of candidate inferred-edge pieces within the set of inferred-edge pieces; and combining the said inferred-edge pieces within at least one said elemental inferral-area, with color data from the source color image, to produce one elemental unit of said second electronic color image.

Claim 53

A computational method for converting a digitized source color image, containing at least three different colors contiguously disposed, into a second electronic color image of different effective spatial resolution, comprising: forming a scanned sequence of examination windows into said digitized color image, said examination windows being at least three pixels high and at least three pixels wide; defining a corresponding scanned sequence of elemental inferral areas smaller than, and substantially centered within, said examination windows; computing, in response to the pixels within the examination windows, at least one inferred-edge piece within at least some of said elemental inferral areas, said computing comprising selecting from among a predefined set of inferred-edge pieces, said selecting comprising detecting major subfeatures shared by a plurality of candidate inferred-edge pieces within the set of inferred-edge pieces; and combining the said inferred-edge pieces within at least one said elemental inferral-area, with color data from the source color image, to produce one elemental unit of said second electronic color image.

Claim 54

The method of claim 51 where exactly two said subfeature detections are combined to select the desired inferred-edge piece.

Claim 55

The method of claim 51 where said detection of a major subfeature serves to inhibit selection of a particular inferred-edge piece.

Claim 56

The method of claim 53 where said inhibitory subfeature is a local checkerboard pattern of pixels in said examination window.

Claim 57

The method of claim 53 where said subfeature is a single-pixel-sized typographic serif.

Claim 58

The method of claim 53 where said subfeature is a single pixel-sized typographic cross-stroke.

Claim 59

The method of claim 51 where selecting said inferred-edge piece includes prioritizing among multiple inferred-edge piece candidates of a given orientation which would be otherwise selected.

Claim 60

A computational method for converting a digitized source color image, containing at least three different colors contiguously disposed, into a second electronic color image of different effective spatial resolution, comprising: forming a scanned sequence of examination windows into said digitized color image, said examination windows being at least three pixels high and at least three pixels wide; defining a corresponding scanned sequence of elemental inferral areas smaller than, and substantially centered within, said examination windows; computing, in response to the pixels within the examination windows, at least one inferred-edge piece within at least some of said elemental inferral areas; and combining the said inferred-edge pieces within at least one said elemental inferral-area, with color data from the source color image, to produce one elemental unit of said second electronic color image; and repeating the foregoing steps to form the second electonic image, where the resolution of the source color image is the same as the nominal resolution of an output device and the said elemental units of said second electronic color image are positioned on scan lines halfway between the scan lines of said computed elemental inferral-areas.

Claim 61

A computational method for converting a digitized source color image, containing at least three different colors contiguously disposed, into a second electronic color image of different effective spatial resolution, comprising: forming a scanned sequence of examination windows into said digitized color image, said examination windows being at least three pixels high and at least three pixels wide; defining a corresponding scanned sequence of elemental inferral areas smaller than, and substantially centered within, said examination windows; computing, in response to the pixels within the examination windows, at least one inferred-edge piece within at least some of said elemental inferral areas; and combining the said inferred-edge pieces within at least one said elemental inferral-area, with color data from the source color image, to produce one elemental unit of said second electronic color image; and repeating the foregoing steps to form the second electonic image, where the resolution of the source color image is the same as the nominal resolution of an output device and the said elemental units of said second electronic color image are positioned on scan lines halfway between the scan lines of said computed elemental inferral-areas.