# Easy3DLaserLine - Laser Line Extraction and Calibration **Easy3DLaserLine** is used to reconstruct 3D objects from a laser-line triangulation system. In a laser-line triangulation system, a laser line is projected on the object to measure. A camera is viewing the laser line from a different angle and position. The line deformation observed by the camera contains the shape information of the measured object.  Scanning the object consists in moving it under the laser line and recording multiple images. From the scanning you can reconstruct its 3D shape.  A Laser Line Extraction (LLE) algorithm is required to create a depth map from a sequence of profiles of the object captured by the camera sensor. The objective of an LLE algorithm is to measure the line position along a vertical profile in every column of a sensor frame, within a user-defined region of interest (ROI). For every step of the object position, the detection analyzes each column of a frame individually and produces a row of output positions, stored as gray values. The figure below illustrates this process.  The class [`ELaserLineExtractor`](../../../doxygen_cpp/classeVision_1_1Easy3D_1_1ELaserLineExtractor.html) [_.NET](../../../doxygen_cs/classeVision_1_1Easy3D_1_1ELaserLineExtractor.html) [_Python](../../../doxygen_python/classeVision_1_1Easy3D_1_1ELaserLineExtractor.html) provides the laser line extraction functionality. The line position returned by the laser line extraction algorithms is relative to the bottom of the region of interest. So, values in the depth map range from 0 (bottom of the ROI) to the height of the ROI.  ## Contents Principles of laser line triangulation and extraction to 3D data using **Easy3DLaserLine**. Benchmark of hardware and software-based line extraction with **Easy3DLaserLine**. How to calibrate the laser-line extraction process. ## Quick Links List of all Classes, Structs and Enumerations of the **Easy3DLaserLine** library. Code snippets for the **Easy3DLaserLine** library. #### SEE ALSO The **3D Laser Line Extraction** sample in **eVision Studio** illustrates how to use the **Easy3DLaserLine** library. The **3D LLE with text reading** sample further illustrates the use of OCR in combination with laser line extraction in a single pipeline.