Data compression system
First Claim
1. A data compression method for compressing acquired image data to make more efficient use of memory space and to expedite the transfer of said data;
- said method comprising the steps of;
aquiring image data,using a scan geometry for scanning the aquired image data region by region in an orderly fashion to obtain at least some of the data to be compressed, said scan geometry being determined by the image data aquisition system used for aquiring the image data,predicting further data to be compressed based on the scanned aquired image data to obtain predicted data,obtaining difference data from differences between said predicted further data and further aquired data,compressing the difference data by encoding the difference data to be compressed using a string length code arrangment for the most prevalent difference data,encoding the second most prevalent data to be compressed with a replacement code that is the shortest,encoding the sequentially next most prevalent difference data with the shortest replacement code not previously used,the step of predicting further data comprising the steps of;
using the scan geometry used for scanning the aquired image data to scan only data regions that have not previously been scanned and are contiguous to scanned data regions,choosing a path from available paths from all of the contiguous scanned data regions that terminate in the region being scanned for predicting purposes,selecting path points on said chosen path that come closer to the center point of the region being scanned that path points of any other available path,determining the values of the selected path points, anddetermining the predicted value of the region being scanned using the determined values of the selected path points.
5 Assignments
0 Petitions
Accused Products
Abstract
A data compression system for use in processing diagnostic image data which uses a predictor to predict future data. The actual data is subtracted from the predicted value to obtain data related difference values. The difference values are coded by coding the most prevalent difference by a code other than the least bit code but further coding the most prevalent number by string length coding, with the most common being the coded with a least bit code, and also coding the next most common difference with a least bit code and the subsequent most prevalent differences with sequential least bit codes to provide compression ratios of over 3:1. A procedure for finding the best predictor in noisy data is provided.
65 Citations
28 Claims
-
1. A data compression method for compressing acquired image data to make more efficient use of memory space and to expedite the transfer of said data;
- said method comprising the steps of;
aquiring image data, using a scan geometry for scanning the aquired image data region by region in an orderly fashion to obtain at least some of the data to be compressed, said scan geometry being determined by the image data aquisition system used for aquiring the image data, predicting further data to be compressed based on the scanned aquired image data to obtain predicted data, obtaining difference data from differences between said predicted further data and further aquired data, compressing the difference data by encoding the difference data to be compressed using a string length code arrangment for the most prevalent difference data, encoding the second most prevalent data to be compressed with a replacement code that is the shortest, encoding the sequentially next most prevalent difference data with the shortest replacement code not previously used, the step of predicting further data comprising the steps of; using the scan geometry used for scanning the aquired image data to scan only data regions that have not previously been scanned and are contiguous to scanned data regions, choosing a path from available paths from all of the contiguous scanned data regions that terminate in the region being scanned for predicting purposes, selecting path points on said chosen path that come closer to the center point of the region being scanned that path points of any other available path, determining the values of the selected path points, and determining the predicted value of the region being scanned using the determined values of the selected path points. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
- said method comprising the steps of;
-
15. An image data compression system for compressing image data to make more efficient use of memory space and to expedite the transfer of said image data said system comprising:
-
acquisition means for acquiring image data to be compressed, means for predicting the data to be acquired, means for obtaining difference values between the acquired data and the predicted data, means for encoding the difference values using string-length coding for the most prevalent difference values, means for encoding the second most prevalent difference value to be compressed using a shortest replacement code, means for encoding each sequentially next most prevalent difference values using the shortest replacement code not previously used; said means for predicting comprising; means for predicting data values only for regions that have not previously been scanned and are contiguous to scanned data regions, means for choosing a path from available paths from all of said contiguous scanned data regions, said path terminating in a region being scanned, means for specifying path points on said path, said path points coming closest to the center point of the region being scanned than path points on any other available path, means for determining the values of the specified path points from the data of the previously scanned regions, and means for predicting the value of the region being scanned from the determined values of the specified path points. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28)
-
Specification