Title: Lesson 2: Image orientation
Course: Photogrammetry applied to drone image acquisition > Section: Course Content

The first step in the photogrammetry workflow is image orientation. The main task of image orientation is to reconstruct the geometric relations between an object point and its image coordinates by calculations, based on the collinearity equations. Thus, through this procedure, three-dimensional (3D) information can be extracted from the images. This lesson will explain some definitions related to photogrammetry, the typical workflow of photogrammetry, image orientation procedures (interior, exterior, relative, and absolute).

Introduction to the lesson

The first step in the photogrammetry workflow is image orientation. The main task of image orientation is to reconstruct the geometric relations between an object point and its image coordinates by calculations, based on the collinearity equations. Thus, through this procedure, three-dimensional (3D) information can be extracted from the images. This lesson will explain some definitions related to photogrammetry, the typical workflow of photogrammetry, image orientation procedures (interior, exterior, relative,and absolute).

Objectives:

The main objectives of this lesson are:

- To explain the concepts of collinearity, pinhole camera model, stereoscopic coverage and forward intersection.
- To understand the interior, exterior, relative, and absolute orientation procedures and their relationship.
- To apply the learned image orientation procedures and techniques to estimate orientation parameters using the designated commercial software (Pix4D) for drone images
- To assess the quality of the conducted orientation processes.

Entrance requirements;

Followed the previous lesson of this course.

Learning activities:

- Study the lesson document (EENSAT_PD_L2_Image_orientation_SlideHandout.pdf), and watch the designated links if described in the document
- Review the background literature (pages 39- 45 of the Community Urban Risk Mapping Cookbook.pdf).
- Prepare exercises as described under “Tasks”

Tasks:

The first task in this lesson is to install the free version“Pix4D discovery” using the following link :https://cloud.Pix4D.com/download/. Please follow the instruction as described in the practical document EENSAT_PD_Practical_L1_5.pdf , section 1.2 processing with Pix4D

The second task is to conduct the practical lesson 2 (chapter 3.2): Image orientation/ calibration using Pix4D. This task will guide you how to run the image orientation process in Pix4Dmapper.

The last task is to submit the answers to the questions in the “Delivery” part of the lesson to the EENSAT Education Portal.

Planned time frame:

14 hours