EP0437074A2
Expired / Lapsed
EP
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Special effects using polar image coordinates
Assignee: Grass Valley Group Inc
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Filing: 1990-12-20
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Granted: —
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Expires: 2010-12-20
Abstract
Abstract Special effects using polar image coordinates produce a new class of television special effects, such as spherical mapping and kaleidoscope effects. Rectangular coordinates for an input image are converted (38) into polar coordinates, and the polar coordinates are mathematically manipulated (40,42) according to the desired special effect. The modified polar coordinates may be applied (46) directly to the rectangular coordinates to produce modified rectangular coordinates that represent the desired special effect, or they may be converted (44) back into rectangular coordinates as the modified rectangular coordinates.
Inventors
- 👤 David E. Lake, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 14:46
CPC Classifications
G; G06; G06T; G06T3/00; G06T3/18; H; H04; H04N; H04N5/00; H04N5/222; H04N5/262; H04N5/2628
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
71 words
In a digital picture manipulator apparatus a mapping function circuit comprising: means for converting (38) rectangular coordinate values representing an input image into corresponding polar coordinate values; means for manipulating (40,42) the polar coordinate values to produce modified polar coordinate values according to a desired effect; and means for modifying (46) the rectangular coordinate values by the modified polar coordinate values to produce modified rectangular coordinate values representing the desired effect.
Claim 2
Dependent Claim
32 words
A mapping function circuit as recited in claim 1 further comprising means for converting (44) the modified polar coordinate values into corresponding rectangular coordinate values to produce the modified rectangular coordinate values.
Claim 3
Dependent Claim
38 words
A mapping function circuit as recited in claim 2 further comprising means for switching (51) between the output of the modifying means and the polar to rectangular converting means as the source of the modified rectangular coordinate values.
Claim 4
Dependent Claim
27 words
A mapping function circuit as recited in claim 1 further comprising means for linearly transforming (36) the rectangular coordinate values prior to input to the converting means.
Claim 5
Dependent Claim
30 words
A mapping function circuit as recited in claim 1 further comprising means for offsetting (32,34) the rectangular coordinate values prior to input to the modifying means and the converting means.
Claim 6
Dependent Claim
20 words
A mapping function circuit as recited in claim 1 further comprising means for offsetting (48,50) the modified rectangular coordinate values.
Claim 7
Dependent Claim
66 words
In a digital picture manipulation apparatus a mapping function circuit comprising: means for converting (38) rectangular coordinate values representing an input image into corresponding polar coordinate values; means for manipulating (40,42) the polar coordinate values to produce modified polar coordinate values according to a desired effect; and means for converting (44) the modified polar coordinate values into output rectangular coordinate values to produce the desired effect.
Claim 8
Dependent Claim
35 words
A mapping function circuit as recited in claim 7 further comprising means for modifying (46) the rectangular coordinate values by the modified polar coordinate values to produce modified rectangular coordinate values representing the desired effect.
Claim 9
Dependent Claim
39 words
A mapping function circuit as recited in claim 8 further comprising means for switching (51) between the output of the modifying means and the polar to rectangular coordinate converting means as the source for the output rectangular coordinate values.
References Cited (Backward Citations)
No citation records indexed.
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