Image analysis – Image compression or coding – Substantial processing of image in compressed form
Reexamination Certificate
1998-12-14
2001-10-23
Couso, Jose L. (Department: 2721)
Image analysis
Image compression or coding
Substantial processing of image in compressed form
Reexamination Certificate
active
06307968
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to the manipulation of compressed data.
BACKGROUND OF THE INVENTION
Modern 3D computer graphic applications require the manipulation, storage and transmission of increasingly complex geometries. Efficient manipulation of such data is critical for the implementation of high performance graphic systems.
Traditionally, complex geometries have been represented as polygonal meshes and parametric surfaces patches such as NURBS. While polygonal meshes are simple to process, they don't constitute a particularly compact representation for a complex, natural surface. Indeed, representing complicated objects might require a large number of polygons. Parametric surfaces obviate most of these disadvantages, but are much harder to render.
Accordingly, many schemes for compact representation of complex geometries have been presented by various authors. An example can be found in Deering M., “Geometry Compression”, Computer Graphics (proc. SIGGRAPH), pages 13-20, August 1995 where a method for compressing geometries and associated information (such as normals and colours) is presented. Deering is directed to real time rendering. Methods to efficiently convert existing models in the format described in Deering can be found in Chow M., “Optimized Geometry Compression for Real-time Rendering” (proc. IEEE Visualization '97), 1997.
A different approach is taken in DeRose T. “Multiresolution Surfaces for Compression, Display, and Editing”, SIGGRAPH '96 Course Notes, Course Number 13, Wavelets in Computer Graphics, where a multiresolution representation of geometric data is described along with its advantages for compression.
Other approaches, such Hoppe H., “Progressive meshes”, Computer Graphics (proc. SIGGRAPH '96), pages 99-108, 1996 and Hoppe H., Popovic J.; “Progressive Simplicial Complexes”, (http://research.microsoft.com/~hoppe) 1997 are based on mesh simplification and allow access to the geometric data at different levels of detail. Of course, in all these cases, there is a decompression overhead on the top of the rendering process.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an alternative form of manipulation of compressed data.
In accordance with a first aspect of the present invention, there is provided a method of spatial manipulation of geometry data describing a graphical object to produce manipulated geometry data, the method comprising the steps of: (a) compressing the geometry data of into a compressed form, the compressing including the step of transforming the data into corresponding frequency domain component data; (b) applying at least one linear transform to the compressed form of the geometry data; (c) decompressing the geometry data, including applying an inverse transform to the frequency domain component data to transform it to produce the manipulated geometry data.
The linear transforms can include for example, one of: translation of the geometry data; scaling of the geometry data; affine transformation of the geometry data; morphing of the geometry data; and applying a dot product to the geometry data.
The step (a) further can comprise: quantizing the frequency component domain data and zeroing the frequency component domain data less then a predetermined magnitude.
The step of transforming the data into corresponding frequency component domain can ideally comprise utilizing a Discrete Cosine, Fourier, Hardamard or Wavelet transform.
The geometry data preferably can include a series of vertex points and color data and/or normal data associated with each of the vertex points.
The dimensionality of the geometry data can be arbitrarily defined.
In accordance with a further aspect of the present invention, there is provided a method of manipulation of geometric data comprising a series of vertex points defining a geometric structure, the method comprising the steps of: transforming the data into a frequency domain to produce corresponding frequency domain data; applying a linear transform to the frequency domain data to produce linearly transformed frequency domain data; inverse transforming the linearly transformed frequency domain data to produce manipulated geometric data.
REFERENCES:
patent: 5546477 (1996-08-01), Knowles et al.
patent: 5592228 (1997-01-01), Dachiku et al.
patent: 5598215 (1997-01-01), Watanabe
patent: 5647024 (1997-07-01), Kawauchi et al.
patent: 5666212 (1997-09-01), Gilge
Couso Jose L.
Davis & Bujold P.L.L.C.
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