Processing of engineering line drawings for automatic input to CAD

Abstract An approach to the conversion of images of line drawings to a format appropriate for computer-aided draughting systems is described. A sequential adaptive line finding technique, combined with ordered storage and automatic guided search is used. The performance of the system on good quality originals reaches the limits set by the level of interpretation employed. On poor quality originals the adaptive nature of the line finder produces a line enhancement effect. The method is seen particularly as a contribution to the solution of the problem of interpretation of imperfect data that is always present in engineering drawing conversion.

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