Mathematical representation of particle orientation and shape can show quantitative differences in particle morphology and microstructures of ceramic green bodies with apparently equiaxed powders. In this work, fourier descriptors and moment invariants were used to quantify the shape of ceramic particles and identify their orientation. Edges constitute a significant portion of the information contained in these images, and hence edge detection forms an important issue in these image processing algorithms.
A Field Emission Scanning Electron Microscope (FESEM, Leo 982) was used to collect images of various ceramic green bodies in order to assess the ceramic particle shape and orientation. The images were collected and displayed as rectangular pixels on the microscope monitor which were then stored as square pixels (square-pixel-interpolation). Application of various edge detection algorithms on the stored images show strong bias to edges in the direction perpendicular to the scanning direction.