LizardTech, Inc. v. Earth Resource Mapping, Inc.

35 F. App'x 918
CourtCourt of Appeals for the Federal Circuit
DecidedMay 22, 2002
DocketNo. 01-1343
StatusPublished
Cited by2 cases

This text of 35 F. App'x 918 (LizardTech, Inc. v. Earth Resource Mapping, Inc.) is published on Counsel Stack Legal Research, covering Court of Appeals for the Federal Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
LizardTech, Inc. v. Earth Resource Mapping, Inc., 35 F. App'x 918 (Fed. Cir. 2002).

Opinion

DECISION

SCHALL, Circuit Judge.

LizardTech, Inc. (“LizardTech”) appeals the decision of the United States District Court for the Western District of Washington that granted the motion of Earth Resource Mapping, Inc., and Earth Resource Mapping Pty Ltd. (collectively, “ERM”) for summary judgment of non-infringement of U.S. Patent No. 5,710,835 (“the ’835 patent”). The ’835 patent is assigned to LizardTech. Because the court erred in construing the asserted claims of the ’835 patent, we reverse and remand.

DISCUSSION

I.

This case relates to technology that enables the storage, retrieval, and display of large digital images. Essentially, large digital images contain copious data, which makes their storage and transmission, in computers and over media (such as wires or cables) in which the capacity to hold data is a scarce and valuable resource, a difficult and salient problem. One solution to this problem involves implementing a process, called a compression algorithm, which reduces the amount of data, and thus memory, required to represent the images, thereby facilitating their storage and transmission. ’835 patent at col., 11. 59-60.

The ’835 patent is directed to an improvement on a particular prior art compression algorithm based on the discrete wavelet transform (“DWT”). Id. at col. 1, 11. 48-53, col. 2, 11. 36-44. As defined in the '835 patent, the DWT is “[a] linear transformation ... that maps a digital input signal to a collection of output sub-bands.” Id. at col. 3,11. 64-67. The DWT transformation takes a piece of digital data from an image, runs it through a specific and complex algorithm, and turns it into multiple subimages (called sub-bands, since each one contains a band of spatial frequencies). The sub-bands then are compressed (into less data) using another [920]*920algorithm.1 In the DWT context, the first “transformation” step comprises running the data through mathematical “low pass” and “high-pass” frequency filters that generate four different subbands. Id. at col 5, 11. 3-36. There exists a reverse DWT decompression scheme that reconstructs the original (or at least close to the original) image from the compressed sub-bands. Id. at col. 1,11. 41-53, col. 5,11. 32-35.

In the prior art implementation of the algorithm, “the entire image data array is stored in computer main memory” while DWT compression is performed. Id. at col. 1, 11. 57-58. The problem with this compression scheme, as applied to very large images with a large amount of data, is that “the memory involved in performing a DWT” of the entire image is “prohibitive.” Id. at col. 1, 11. 60-61. Therefore, it is preferable to compute the DWT by dividing such a large digital image into subsections, called “tiles,” and then “computing the DWT in sections.” Id. at col. 1, 11. 66-67, col. 2, 11. 48-51. This “tiling” technique, though requiring less memory to perform the DWT compression of the images, creates imperfections, or “edge artifacts” in the images-visible upon decompression and viewing-at the edges between the tiles. Id. at col. 2,11. 4-8.

LizardTech’s ’835 patent, for purposes relevant to this appeal, claims a method for performing DWT-based compression on large images in subparts using a technique that minimizes the formation and appearance of such edge artifacts.2 First, the patent calls for breaking the large image (designated in the patent as I(x,y)) into “discrete tile image data subsets [designated as Ty(x,y)] that, upon superposition, form the complete set of image data I(x,y).” Id. at col. 2, 11. 48-51. In other words, the entire image I(x,y) is broken up into separate pieces Ty(x,y) called “tiles” that, reassembled, would form the entire image. Then, the tiles are “successively input[ ] ... in a selected sequence” into a DWT-based compression algorithm. Id. at col. 2, 11. 53-54. Without more, this process would be identical to the prior art DWT tiling solution described above and would accordingly suffer from the attendant “seam” and “edge artifact” problems. However, the patent seeks to mitigate these problems, which occur at the juncture of tiles, by accounting for the DWT calculations from previous tiles in performing the DWT algorithm on the present tile. That is, the result of the DWT process for tile 2 may depend not only on the particular data input from the area of the image covered by tile 2, but also the results (which include outputs called “DWT coefficients”) of the DWT calculation from neighboring tile 1. More specifically, the patent calls for storing the previous DWT coefficients (part of the output of a DWT calculation) in the accessible portion of the computer memory for use in performing DWT on ensuing tiles and then ultimately transferring that data to a more permanent memory. Id. at col. 2, 11. 45-60. Before being transferred (or “dumped”) into secondary memory, the coefficients are compressed periodically. Id. at col. 8, 11. 5-9.

Claim 1 of the ’835 patent, which the parties have agreed is a representative [921]*921claim for purposes of infringement, reads, with emphasis added, as follows:

A method for selectively viewing areas of an image at multiple resolutions in a computer having a primary memory for data processing and a secondary memory for data storage, the method comprising the steps of:
storing a complete set of image data array I(x,y) representing said image in a first secondary memory of said computer;
defining a plurality of discrete tile image data Ty(x,y) subsets, where said complete set of image data I(x,y) is formed by superposition of said discrete tile image data Ty(x,y);
performing one or more discrete wavelet transformation (DWT)-based compression processes on each said tile image data Ty(x,y) in a selected sequence to output each said discrete tile image data Ty(x,y) as a succession of DWT coefficients in a succession of subband sets, where one subband of each set is a low-resolution representation of said discrete tile image data Ty(x,y) to form a sequence of low resolution representations of said image data array I(x,y) to selected resolutions;
maintaining updated sums of said DWT coefficients from said discrete tile image Ty(x,y) to form a seamless DWT of said image and storing said sums in a first primary memory location of said computer;
periodically compressing said sums and transferring said compressed sums to a second secondary memory to maintain sufficient memory in said primary memory for data processing, wherein said secondary memory contains stored DWT wavelet coefficients;
selecting a viewing set of said image data array I(x,y) to be viewed at a desired resolution; and forming from said subset of said stored DWT wavelet coefficients a computer display of said viewing set of said image data at said desired resolution.

’885 patent at col. 11,11. 38-62.

II.

On October 6, 1999, LizardTeeh filed suit against ERM, alleging infringement of the ’835 patent, copyright infringement, breach of contract, false designation of origin, false description, and common law trademark infringement. Specifically, LizardTech contended that ERM’s geospatial imaging software product, called ER Mapper, infringed various claims of the ’835 patent.

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Related

LizardTech, Inc. v. Earth Resource Mapping, Inc.
424 F.3d 1336 (Federal Circuit, 2005)
Laser Technology, Inc. v. Nikon, Inc.
215 F. Supp. 2d 1135 (D. Colorado, 2002)

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Bluebook (online)
35 F. App'x 918, Counsel Stack Legal Research, https://law.counselstack.com/opinion/lizardtech-inc-v-earth-resource-mapping-inc-cafc-2002.