Invalidity dossier
US 5392419
Language identification system and method for a peripheral unit
Current assignee: HP Inc
Added 9/24/2026, 1:50:18 AM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5,392,419
Title: Language identification system and method for a peripheral unit
Inventor: Sean E. Walton
Original Assignee: Hewlett Packard Co. (current assignee listed as HP Inc.)
Application No.: US07/825,479 | Filed: 1992-01-24 | Priority: 1992-01-24 | Granted/Published: 1995-02-21
Legal status: Expired – Fee Related; anticipated expiration listed as 2012-02-21
Source: https://patents.google.com/patent/US5392419/en
Purpose: A peripheral unit (e.g., printer, plotter, facsimile) attached to a network may receive different peripheral control languages (the text names PCL and PostScript) from different connected computers. Because initial identification code sequences may be disabled or may appear erroneously within another language's data stream, the patent addresses automatic identification of the incoming language so the peripheral can interpret and execute it correctly.
Plain-language scope: The system buffers a block of incoming data (preferably 256 bytes) and runs a separate "voter" module per expected language. A voter analyzes the block's syntax to find "keys" — defined portions that vote For or against a language — and produces For and against tallies. Each tally entry is an identified key count multiplied by a "skew" value reflecting the key's importance in the syntax and context. The tallies are compared; if they are too close (uncertainty), a further syntactical characteristic of the block resolves it; otherwise the larger tally indicates a value. A "decider" module receives the voter outputs and determines the most likely language, then directs the CPU to the corresponding decoding software.
Not established by this excerpt: The full detailed description, the complete claims and their exact scope, the complete flow diagrams (FIGS. 8–11), specific skew/weight and context table values, and any comparison to prior art beyond the described QMS ESP product. Legal status and assignee listings are noted as assumptions per the source.
Generated 10/1/2026, 9:31:04 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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