Invalidity dossier
US 5974184
Intra-macroblock DC and AC coefficient prediction for interlaced digital video
Current assignee: Google Technology Holdings LLC
Added 9/23/2026, 1:33:37 PM
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 5,974,184 A
Title: "Intra-macroblock DC and AC coefficient prediction for interlaced digital video"
Patent number / application: US 5,974,184 A; Application No. US 08/957,511.
Inventors: Robert O. Eifrig, Xuemin Chen, Ajay Luthra.
Original assignee: General Instrument Corp. Current assignee listed: Google Technology Holdings LLC.
Key dates (as listed; dates are assumptions, not legal conclusions):
- Prior art date / priority date: 1997-03-07
- Filing date: 1997-10-24
- Publication/grant: 1999-10-26
- Anticipated expiration: 2017-10-24
- Legal status: Expired – Lifetime
Foreign counterparts listed: CA 2230422, EP 0863673, TW 373408, NO 980948, AU 57399/98, CN 981080537, KR 1019980007629, JP 10073077, BR 9800852.
Purpose and plain-language scope (from the supplied excerpt): The patent concerns compressing/decompressing digital video using transform coding, specifically discrete cosine transform (DCT) coding. Its classifications place it in adaptive coding, selection of coding/prediction mode, prediction within a coding mode, and prediction according to display mode (e.g., interlaced vs. progressive). The title indicates that DC and AC transform coefficients are predicted for intra-coded macroblocks, and that this prediction is designed for interlaced digital video. Prior-art keywords listed are: block, spatial transform, transform coefficients, current, and field mode — suggesting the technique involves choosing/using a field mode and predicting coefficients of a current block from previously coded blocks via a spatial transform (see classifications H04N19/60, /625, /103, /105, /112, /176, /50, /503).
Source: https://patents.google.com/patent/US5974184/en
What the excerpt does not establish: The supplied text contains no claims, no written description, no drawings, no detailed-embodiment text, and no inventor-supplied problem statement. It therefore does not establish the specific prediction rules, scan/DC-prediction ordering, field/frame selection logic, or the precise scope of any claim. It also does not establish the accuracy of the assignee listing, priority claims, or legal status, which the source itself flags as assumptions or non-legal conclusions. No litigation, ownership-transfer, validity, or prior-art analysis is offered here.
Generated 10/1/2026, 9:53:03 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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