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AssigneeCompression Labs, Inc.
InventorsWilliam K. Pratt, Ronald S. Bader, Wen-Hsiung Chen, Lyle V. Rennick, Robert H. Wallis
Estimating the term…
A dual mode facsimile data compression technique which possesses the advantage of symbol recognition and extended run-length coding methods. In operation, a symbol blocking operator isolates digital raster data representing valid alphanumeric characters and document symbols. The first symbol encoungered is placed in a memory or library and as each new symbol is detected, it is compared with each entry of the library. If the comparison is within a predetermined tolerance, a library identification code representing the symbol is generated and transmitted along with the symbol location coordinates. Otherwise, the new symbol is placed in the library and its digital pattern and location is transmitted. A scoring system determines which elements of the library are to be replaced by new prototypes once the library is filled. Non-isolated symbols are coded by a two-dimensional run-length coding method for transmission.
In a facsimile coding system, the method comprising the steps of segmenting an uncompressed digital raster data stream having pixels representing symbols and non-symbols on a document into spatially segmented symbols and non-symbols, coding said segmented symbols and non-symbols to form representative digital codes and combining said digital codes into a digital compressed data stream.
In a facsimile coding system, the method comprising the steps of dynamically segmenting an uncompressed data stream having pixels representing symbols and non-symbols on a document into spatially segmented symbols and non-symbols by removing all symbols from the document at their location thereby leaving a residue of non-symbols, encoding said segmented symbols and said residue to form symbol and residue codes and combining said symbol and residue codes into a compressed digital data stream.
In a facsimile decoding system, the method comprising the steps of receiving a digital compressed data stream including data representing encoded spatially segmented symbol and non-symbol codes, separating said symbol and non-symbol codes, decoding said symbol code thereby forming first raster data, decoding said non-symbol code thereby forming second raster data, and combining said first and second raster data into an uncompressed raster data stream representing symbols and non-symbols on a document.
In a facsimile coding system, the method comprising the steps of dynamically segmenting an uncompressed data stream having pixels representing symbols and non-symbols on a document into spatially segmented symbols and non-symbols by removing all symbols from the document at their location thereby leaving a residue of non-symbols, encoding said segmented symbols and said residue to form symbol and residue codes, combining said symbol and residue codes into a compressed digital data stream, transmitting said compressed data stream from a first location to a second location, receiving said digital compressed data stream, separating said symbol and residue codes, decoding said symbol codes thereby forming first raster data, decoding said residue codes thereby forming second raster data, combining first and second raster data into a raster data stream representing said symbols and non-symbols on said document.
In a facsimile coding system, the method comprising the steps of scanning raster data having a plurality of black and white pixels representing an image for a first black pixel having white pixels disposed immediately preceding and above said first black pixel, blocking a group of black pixels contiguous to said first black pixel thereby forming a trial block, determining whether a symbol is isolated within said trial block, transferring said trial block to a residue if no symbol is isolated within said trial block and encoding same, comparing an isolated symbol block with stored symbols to determine a match, forming identification codes representing matched symbols, storing unmatched symbols, generating a pixel contents code representing said unmatched symbols, and combining said encoded data, said identification codes and said contents code into a digital bit stream.
In a facsimile coding system, the method comprising the steps of segmenting a digital uncompressed raster stream representing symbols and non-symbols into spatially segmented symbols and non-symbols by removing all symbols from the document at their location thereby leaving a residue of non-symbols, matching said segmented symbols with stored symbols, generating identification codes representing sufficiently matched segmented symbols, forming the exclusive-OR of said matched segmented symbols with said matched stored symbols, combining said residue and said exclusive-OR, encoding said combined residue and exclusive-OR to form representative digital codes, and combining said identification codes and said digital codes into a compressed digital data stream.
In a facsimile coding system, the method comprising the steps of forming a digital raster data stream having black and white pixels representing symbols and non-symbols on a document, dynamically segmenting the data stream into spatially segmented symbols and non-symbols, encoding the segmented non-symbols thereby forming first digital codes representing said segmented non-symbols, matching said segmented symbols with stored symbols, generating identification codes representing matched symbols, storing unmatched segmented symbols, generating second digital codes representative of said unmatched segmented symbols, and combining said first and second digital codes and said identification codes into a compressed digital data stream representing said document.
A facsimile coding system comprising means for segmenting an uncompressed digital raster data stream having pixels representing symbols and non-symbols on a document into spatially segmented symbols and non-symbols, encoding said segmented symbols and non-symbols to form representative digital codes, and means for combining said digital codes into a digital compressed data stream.
A facsimile coding system comprising means for dynamically segmenting an uncompressed data stream having pixels representing symbols and non-symbols on a document into spatially segmented symbols and non-symbols by removing all symbols from the document at their location thereby leaving a residue of non-symbols, means for encoding said segmented symbols and said residue to form symbol and residue codes and means for combining said symbol and residue codes into a compressed digital data stream.
A facsimile decoding system comprising means for receiving a digital compressed data stream including data representing encoded spatially segmented symbol and non-symbol codes, means for separating said symbol and non-symbol codes, means for decoding said symbol codes thereby forming first raster data means for decoding said non-symbol codes thereby forming second raster data, and means for combining said first and second raster data into an uncompressed raster data stream representing said symbols and non-symbols on a document.
A facsimile coding system comprising means for dynamically segmenting an uncompressed data stream having pixels representing symbols and non-symbols on a document into spatially segmented symbols and non-symbols by removing all symbols from the document at their location thereby leaving a residue of non-symbols, means for encoding said segmented symbols and said residue to form symbol and residue codes, means for combining said symbol and residue codes into a compressed digital data stream, means for transmitting said compressed data stream from a first location to a second location, means for receiving said transmitted compressed data stream, means for separating said symbols and residue codes, means for decoding said symbol codes thereby forming first raster data, means for decoding said residue codes thereby forming second raster data, and means for combining said first and second raster data into a raster data stream representing said symbols and non-symbols on said document.
A facsimile coding system comprising means for scanning raster data having a plurality of black and white pixels representing an image for a first black pixel having white pixels disposed immediately preceding and above said first black pixel, means for blocking a group of black pixels contiguous to said first black pixel thereby forming a trial block, means for determining whether a symbol is isolated within said trial block, means for transferring said trial block to residue coding means if no symbol is isolated within said trial block and encoding same, means for comparing an isolated symbol block with stored symbols to determine a match, means for forming identification codes representing matched symbols, means for storing unmatched symbols, means for generating a pixel contents code representing said unmatched symbols, and means for combining said encoded data, said identification codes and said contents code into a digital bit stream.
A facsimile coding system comprising means for segmenting a digital uncompressed raster data stream representing symbols and non-symbols into spatially segmented symbols and non-symbols by removing all symbols from the document at their location thereby leaving a residue of non-symbols, means for matching said segmented symbols with stored symbols, means for generating identification codes representing sufficiently matched segmented symbols, means for forming an exclusive-OR signal representing the difference between said matched segmented symbols with said matched stored symbols, means for combining said residue and said exclusive-OR signal, means for encoding said combined residue and exclusive-OR signal to form representative digital codes, and means for combining said identification codes and said digital codes into a compressed digital data stream.
A facsimile coding system comprising means for forming a digital raster data stream having black and white pixels representing symbols and non-symbols on a document, means for dynamically segmenting the data stream into spatially segmented symbols and non-symbols, means for encoding the segmented non-symbols thereby forming first digital codes, means for matching said segmented symbols with stored symbols, means for generating identification codes representing matched symbols, means for storing unmatched segmented symbols, means for generating second digital codes representing said unmatched segmented symbols, and means for combining said first and second codes and said identification codes to form a compressed digital data stream representing said document.
Dependencies are inferred from the claim text.