Wood Inspection

Application Type	Inspection
Image Characteristics	Monochrome; Low Contrast
Image Processing Tool(s)	Lookup Table; Thresholding; Advanced Morphology; Particle Analysis

The wood inspection example checks the surface of wood planks for structural defects using a lookup table, an automatic threshold, binary image processing, advanced morphology, and particle analysis.

Lookup Table: Square Root—Enhances the appearance of the pixels in the image with low grayscale values. Structural defects on the wood surface appear as slightly darker regions in the image. A lookup table that applies a square root function to the image helps to enhance the difference between the defects and the surface of the wood.

Threshold: Auto-Threshold—Entropy—Separates the areas in the image that may be defects from the rest of the wood surface. An automatic thresholding technique is applied to create a binary image. An automatic threshold has the advantage of being independent of the imaging conditions.

Adv. Morphology: Remove Small Particles—Removes small noise particles from the binary image. Particles that are removed by an iteration of erosion are assumed to be noise particles.

Adv. Morphology: Remove Border Objects—Removes particles that touch the border of the image. Complete information about particles that touch the border of the image is not available, so the particles are removed from further analysis.

Particle Analysis—Determines characteristics of each particle (defect) in the image. You can compute up to 50 different properties of the structural defects.