| 摘要 |
PURPOSE:To approximate an original pattern in a high speed with a small volume of information, by discriminating a line or an arc on a basis of the transition of respective angular changes of data which are detected and divided by magnitudes, polarities, and accumulation of angular changes. CONSTITUTION:Linear pattern data is stored in a register 1, and an angular change is calculated in an angualr change calculating part 2 on a basis of its contents and is stored in a register 3. This angular change is compared with thresholds alpha and beta in angular change magnitude discriminating parts 6 and 7. A division point which becomes a bending point of data is detected in the discriminating part 6, and a division point where data is changed with gentle bending is detected on a basis of the result of the discriminating part 7 by a polarity discriminating part 8 if the angular change has a polarity different from that of the preceding angular change. Angular changes of the register 3 are accumulated in a cumulative angle calculating part 4, and the absolute value of accumulation and a threshold gamma are compared with each other to detect volute division points in a cumulative angle discriminating part 9. Respective outputs of discriminating parts 6, 8, and 9 are inputted to a division discriminating part 10, and the discrimination result is sent to a line/arc discriminating part 12, and an arc or a line is discriminated on a basis of this result and preceding information 11, and the radius of the arc or the inclination of the line is calculated in a parameter calculating part 13. |
