EP0544510A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Split-level frame buffer
Assignee: Xerox Corp
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Filing: 1992-11-25
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Granted: —
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Expires: 2012-11-25
Abstract
Abstract A single, split-level frame buffer (10) for use in a color imaging system includes a plurality of pixels (12) having a first resolution level. A plurality of bits are provided for each pixel so as to enable accurate pictorial imaging. The frame buffer includes pixels (14) having a resolution level which is higher than the first resolution level. Pixels on the edges of objects being imaged are replaced by the higher resolution pixels to provide images wherein object edges have high-resolution while object interiors have moderate resolution. In using a single frame buffer, images having more than one level of resolution are generated which do not require separation and merging operations.
Inventors
- 👤 Steven J. Harrington
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 00:25
CPC Classifications
G; G09; G09G; G09G5/00; G09G5/36; G09G5/02; G09G2340/00; G09G2340/04; G09G2340/0407
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
66 words
A single frame buffer (10) for use in a color imaging system, said frame buffer comprising a plurality of pixels (12) having a first resolution level and a plurality of bits per pixel, said frame buffer further comprising pixel replacement means for replacing any of said pixels with substitute pixels, said substitute pixels (14) having a resolution level which is higher than said first resolution level.
Claim 2
Dependent Claim
22 words
A frame buffer according to claim 1, wherein said plurality of bits comprise a number of bits sufficient to represent pictorial images.
Claim 3
Dependent Claim
25 words
A frame buffer according to claim 1 or claim 2, wherein said pixel replacement means replaces pixels at locations along edges of objects being imaged.
Claim 4
Dependent Claim
37 words
A frame buffer according to any one of claims 1 to 3,, wherein some color values serve as an indicator of whether said pixel replacement means is to replace a pixel with said substitute pixels (Figs. 2D,2E).
Claim 5
Dependent Claim
46 words
A frame buffer according to any one of claims 1 to 3, wherein at least one bit of a color separation in a pixel entry serves as an indicator of whether said pixel replacement means is to replace a pixel with said substitute pixels (Figs. 2B,2C).
Claim 6
Dependent Claim
43 words
A frame buffer according to any one of claims 1 to 5, said pixel replacement means comprising a pointer (16) provided at a location of a pixel being replaced, said pointer providing an instruction to replace said pixel with said substitute pixels (Fig.2A).
Claim 7
Dependent Claim
69 words
A frame buffer according to any one of claims 1 to 3, wherein said pixel replacement means comprises a hash (18) and a hash table (20), said hash being provided at a location of a pixel (30) being replaced, said hash table storing pixel location and said substitute pixels according to hash table entries, said hash providing an index to said entries in said hash table (Figs. 3A, 3B).
Claim 8
Dependent Claim
53 words
A frame buffer according to any one of claims 1 to 3, wherein said substitute pixels are arranged into scan line buckets, said pixel replacement means searching said scan line buckets for an appropriate bucket, said appropriate bucket including substitute pixels having a desired resolution higher than said first resolution level (Fig. 4).
Claim 9
Dependent Claim
28 words
A frame buffer according to claim 8, wherein entries in said scan line buckets are sorted into raster order to facilitate retrieval as said frame buffer is imaged.
Claim 10
Dependent Claim
41 words
A frame buffer according to any one of claims 1 to 3, wherein said pixel replacement means comprises a list of replacement colors and a mapping means providing the correspondence between the replacement colors and the said substitute pixels (Figs 5A-5B).
Claim 11
Dependent Claim
26 words
A frame buffer according to claim 10, wherein said list (32) of replacement colors contains only two colors and said mapping means is a bitmap (34).
Claim 12
Independent Claim
39 words
A method of color imaging using a single frame buffer according to any one of the preceding claims, said method comprising replacing any of said pixels having a first resolution level with substitute pixels provided in said frame buffer.
References Cited (Backward Citations)
No citation records indexed.
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