| US 7,539,348 B2 | ||
| Digital map shape vector encoding method and position information transfer method | ||
| Shinya Adachi, Kanagawa (Japan) | ||
| Assigned to Panasonic Corporation, Osaka (Japan) | ||
| Filed on Oct. 11, 2007, as Appl. No. 11/870,731. | ||
| Application 11/870731 is a continuation of application No. 10/169705, granted, now 7,333,666, previously published as PCT/JP02/004267, filed on Apr. 26, 2002. | ||
| Claims priority of application No. 2001-134318 (JP), filed on May 01, 2001; and application No. 2001-220061 (JP), filed on Jul. 19, 2001. | ||
| Prior Publication US 2008/0031534 A1, Feb. 07, 2008 | ||
| Int. Cl. G06K 9/46 (2006.01); H03M 7/30 (2006.01) | ||
| U.S. Cl. 382—243 [382/101; 382/245; 382/159; 382/113; 341/50; 341/76; 341/150] | 3 Claims |
| 1. A method of coding shape data represented by a coordinates string using one or more processors and at least one storage
device, the method comprising the steps of:
sampling the shape data at a constant distance (L);
representing the sampled shape data by data of the constant distance (L) and data of an angle (θ);
converting, using one or more of said one or more processors, a data string of the angle (θ) into a data string of an deflection
angle (Φ)representing a direction difference between the angles (θ)of adjacent sampling points;
converting, using one or more of said one or more processors, the data string of the deflection angle (Φ) into a data string
of a predicted difference value (ΔΦ) which is a difference between a predicted value (Sj) and the actual angle; and
variable-length-coding, using one or more of said one or more processors, the data string of the predicted difference value
for storing in the at least one storage device.
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