THE OPTIMAL THRESHOLD ALGORITHM AND CANNY BASED EDGE DETECTION IN OPTICAL AREA AND DIMENSION MEASUREMENT
Abstract
The fluctuating light conditions cause troubles in image processing based area and dimension measurement. This article describes the hardware implementation and measured properties of canny-based edge detection and an optimal thresholding method. Both units were implemented on proprietary FPGA-based image processing system for “on the fly” measurement. The optimal threshold algorithm presented is able to adapt to changed light conditions and calculates the object size counting the pixels above threshold. The other method uses the first and the second differentiation combined with low-pass filter do locate the object edges and calculates the object size by subtracting their positions. As it uses the maximal slope as edge criteria it is also resistant against illumination changes.
Event details
- Event
- Exploring New Frontiers of Instrumentation and Methods for Electrical and Electronic Measurements
- Technical Committee
- TC4
- Place
- Florence, ITALY
- Time
- 22 September 2008 - 24 September 2008
- Website
- http://www.imeko2008.org/