Compaction and decompaction of non-coded information bearing signals

The machine-implemented method of digitally processing image data signals received as a raster array of 0 and 1 bit signals wherein the image is represented by the pattern of 1s and 0s in the array, the array being addressable by horizontal and vertical coordinates, each bit signal being separately identifiable in said array;

• including the machine-executing steps of:
• dividing said array of bit signals into segments of said bit signals such that each segment is separately addressable;
• scanning the array for identifying each non zero segment and grouping successively scanned non zero segments, irrespective of nonzero informational content of such nonzero segments, into segment groups with each segment group having a predetermined maximal number of segments and possibly less than said maximal number of segments;
• identifying each group of segments by the horizontal and vertical coordinate of the first scanned bit (whether 0 or 1) in the first segment scanned of each group and storing an index to all segments using said identifying group coordinates;
• processing said array by processing said identified groups;
• and
• reconstructing said array from said groups of segments and visually presenting said image based upon said reconstructed segment.

In a machine-implemented method of compacting image data consisting of an array of binary signals with each said binary signal representing a pel of the image as presentable in a raster of pels, a first binary signal representing a background pel and a second binary signal representing a foreground pel;

• the improvement including the machine-executable steps of:
• dividing said array of binary signals into segments which are subintegral rectangular arrays of binary signals of the binary signal array;
• iteratively performing the following steps (A) through (E) until all of said segments having at least one of said second binary have been identified with an address, each segment having a second binary signal being a foreground segment;
• (A) for each of said foreground segments, identifying all contiguous foreground segments in a first orthogonal direction and in a second orthogonal direction for identifying all such contiguous foreground segments which are also contiguous to the contiguous foreground segments in a first orthogonal direction;
• (B) totalizing the number of said foreground segments identified in the immediately preceding step (A);
• (C) repeating steps (A) and (B) until all possible rectangular groups of such contiguous segments are identified;
• (D) finding a rectangular group having a largest number of said foreground segments are assigning an address to such group;
• (E) creating an indication that all of said foreground groups in said largest group identified in the immediately preceding step (D) are now not foreground segments;
• storing in an addressable data storage unit at addressable data storage locations all of said groups of identified foreground groups with an indication of the logical location thereof in said array of binary signals as compacted representation of said image;
• and
• creating and storing a table containing all of said assigned addresses and the respective stored locations of said groups of foreground segments whereby said image can be machine decompacted by machine addressing said groups of stored foreground segments via said table.

In visual-image-producing apparatus adapted to store digital signals representing the image to be presented as an array of binary signals wherein a first binary signal represents an image background pel and a second binary signal represents an image foreground pel in identical spatial relations as pels of the visual image;

• the improvement, including in combination:
• size means for electrically indicating the size of the image to be presented as the number of said pels in an array corresponding to said array of binary signals;
• segment means for electrically indicating segments of said binary signal array, each of said segments being a subarray of said binary signals which is a subintegral of the array of binary signals;
• blank means for electrically indicating which of said segments contain at least one of said second binary signals;
• storage means coupled to said size means, said segment means and said blank means for storing all of said segments including at least one of said second binary signals and none of said segments not containing said at least one of said second binary signals and including directory means for indicating the array position of said stored segments;
• and
• image presenting means coupled to said storage means and said directory means for accessing said storage means to obtain said stored segments and for presenting such accessed segments as a part of said image and presenting background pels in all segment areas of the image array corresponding to segments of said image to be presented but not stored.

In an image-presentation device having visual-image-presenting means for generating a visual likeness of an image as a raster of pels in a rectangular array;

• said image being represented by a like-sized array of digital signals wherein each said digital signal represents one pel;
• the improvement including in combination:
• data storage means for storing a compacted digital signal representation of an image to be presented as a plurality of segments of the array wherein each stored segment includes at least one digital signal representing at least one foreground pel of the image and any segment including background pel indicating digital signals only not being stored therein;
• each said segment having a rectangular subarray of digital signals for representing pels of said image to be presented;
• said segments being stored as rectangular groups of contiguous segments each one of said contiguous segments including said at least one digital signal;
• directory means in said data storage means for indicating the data storage address of said stored rectangular groups and storing an identified spatial location of each said rectangular groups in said rectangular array, respectively;
• and
• presenting control means coupled to said directory means, said data storage means and said visual-image-presenting means for building a visual image by accessing said stored segments and overlaying same onto a visual array of background pels equal in size to said rectangular array at spatial locations indicated by the respective identified spatial locations.

In a printer of the all-points-addressable raster type having the elements of a channel adapter, a digital processor, a working store having a plurality of addressable registers which are allocatable for program-defined data storage, a text decoder, a raster pattern store, a print buffer and a page raster unit for visually presenting images received as raster patterns from said raster pattern store or said working store, means intercoupling all of the above-recited elements and programs is said working store for enabling the digital processor to operate the elements in a coordinated manner for printing the image;

• the improvement including, in combination:
• a line index table in said working store for addressably relating lines of said raster to predetermined data storage areas of said working store;
• an offset table in said working store occupying said predetermined data storage areas and in each of said predetermined data storage areas storing a line offset for data to be printed, a number of data units to be printed and an address of said raster pattern store which stores such data units to be printed, and means linking said predetermined data storage areas for each line in said line index table;
• a blank array in said working store having a plurality of addressable bit positions each for storing a first binary signal for signifying that a corresponding data segment has all background-indicating signals and a second binary signal for signifying that a corresponding data segment includes at least one foreground-indicating signal;
• first program means stored in said working store for enabling said digital processor to operate said elements to receive a rectangular array of raster digital signals and for dividing said raster digital into segments, each of said segments having a given number of said raster digital signals and for relating each of said segments to a respective one of said blank array bits to become a corresponding segment thereof;
• second program means in said working store for enabling said digital processor to scan each of said received segments and for setting the related blank array bit to store a first or a second binary signal in accordance with each such segment containing all background data signals or including at least one foreground datum signal;
• third program means in said working store for enabling said digital processor to identify all of said segments in said line index table and said offset table that contain said at least one foreground datum signal and for storing such segments in said raster pattern store as addressable characters;
• and
• fourth program means in said working store for enabling said digital processor to print said received rectangular array of raster signals by said coordinated operation by supplying said stored segments to said print buffer at offsets indicated by said offset table.