Extracting Shapes from Shadows – What is it?

Shape extraction from shadows is a 3D technique of measuring slope and curvature used in automated quality control. It is generally applied on flat surfaces and inline surface inspections and enables the reliable detection of surface irregularities such as cracks, scratches, pores or indentations.

In this method, the object under examination is illuminated from four different directions respectively. Each direction is captured by grayscale imaging. The slope and curvature information provided by surface shading is used in image evaluation to determine surface quality. This method allows reliable detection of small irregularities in the structure geometry even on highly reflective or shiny surfaces.

Your benefits:

  • Safe and precise detection of even slight irregularities in structures and shapes with the help of high-resolution cameras
  • Cost-effective and easy surface inspection of almost any material, even highly reflective metal objects
A coin was illuminated from four different angles to evaluate grayscale images. The resulting image reveals even the smallest surface irregularities, such as scratches.

Camera Integrated Lighting Control

Baumer supports you in your application of extracting shapes from the shadows with industrial cameras with four individually triggered power outputs. These cameras offer pulse width modulation and up to 120 W output power (max. 48 V / 2.5 A). The illumination and brightness level are respectively triggered by the camera and the image is then captured and transmitted to a PC for evaluation. This eliminates the need for a separate lighting controller, simplifies system design and reduces cost and labor for wiring, programming and documentation.

The integrated fast sequence controller and internal memory (for image capture in Burst Mode) minimize required review time at high process speeds.

Your benefits:

  • Easy and cost-effective system design thanks to integrated lighting and brightness control
  • Integrated, GenICam-compatible sequencer to control lighting and trigger image acquisition directly from the camera
  • Saves cost and time by reducing wiring and programming effort as it does not require an external lighting controller
  • Reliable detection of the smallest surface irregularities with resolution up to 65 megapixels