Data compression and file segmentation in directmodel JT datastores
US8019788B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2002 |
| Grant date | Sep 13, 2011 |
| Priority date | — |
| Expiry date | Apr 24, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M7/30
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The size of lightweight JT data files containing CAD data is reduced by employing lossy compression where acceptable for portions of the CAD data, such as 3D geometry data. Dictionary-based lossless compression for the remaining portions is augmented by exploiting common repeated structures for some portions, such as precise Brep data, and compressing separate but similar data, such as all metadata for a given part and all scene graph data, together as a single block. The compressed data is then written in separate, uniquely identified data segments indexed in a table of contents, allowing quick access to any data segment for streaming.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.