Photogrammetry toolkit

Computer requirements:

Arpenteur can run on Windows, Mac OS and Linux.
To run Arpenteur on your computer JAVA need to be installed. Arpenteur is running with JAVA Version 8 freely downloadable here

Warning: to run full features of Arpenteur we recommend the following computer configuration:
PC, MAC LINUX: configuration 16 GB RAM with a decent Graphic card
However, in the tests carried out most of Arpenteur’s features can run in PC, Mac and LINUX computers with more standard configurations. In the tests carried out in PC configuration PC and Mac configurations Mac run efficiently Arpenteur

Recommendation on underwater photography equipment

For photogrammetric analysis you can use a wide array of cameras, housings, electronic strobes and video lights settings. However, since during a standard photogrammetric survey you will obtain hundreds of photos and bottom time is limited, we recommend you to use professional cameras settings guaranteeing high performance and reliability. We usually work with reflex cameras (e.g. Nikon D300, D7000) with 20 mm lenses in housings (Sea & Sea, Aquatica, Issota) and two electronic strobes (e.g. Ikelite DS160) to avoid shadows. However, lighter and less expensive equipment based on compact cameras in housings equipped with video lights can be used as well.

To avoid problems with the autofocus we recommend you to set the focus to manual once you find the focus distance to carry out the red coral surveys. Since the photos have to be taken from similar distances.

To carry out the red coral surveys a quadrat we will use a specially designed quadrat 20 x 20 cm with specific tags. The purpose of the tags is to have to be used speed up the image processing required for photogrammetry analysis. In particular, the tags are automatically recognized by Arpenteur in order to create the 3D models from the sets of photos from the same scene taken from different angles and set the scale. You can print the quadrat using a two color 3D printer using this file [soon]

Once you have the quadrat to facilitate the surveys you must glue plastic screws in each corner as well as gluing corks or other material to ensure positive buoyancy. This complements are required to ensure a stable position of the quadrat within the red coral populations during the surveys.

Computer requirements:

Arpenteur can run on Windows, Mac OS and Linux.
To run Arpenteur on your computer JAVA need to be installed. Arpenteur is running with JAVA Version 8 freely downloadable here

Warning: to run full features of Arpenteur we recommend the following computer configuration:
PC, MAC LINUX: configuration 16 GB RAM with a decent Graphic card
However, in the tests carried out most of Arpenteur’s features can run in PC, Mac and LINUX computers with more standard configurations. In the tests carried out in PC configuration PC and Mac configurations Mac run efficiently Arpenteur

In order to process the (two or three) photos obtained from each quadrat, the corresponding file must be renamed following a specific pattern that is used by Arpenteur to recognize the photo sets that belong to the same quadrat position.

Model generation is the step in which we compute the external orientation (EO) of the camera, i.e. the position of the camera, respect to the quadra, when the photo were made. This step is crucial for the measurement (see next step) and an indicator of precision is provided for each model.

Once the model are computed (EO) measurement on specific zone of the photograph can be done by identifying homolougous points in two or three photograph. As relevant points are not always easy to identify an automatic approach is not relevant. We offer an interface to identify relevant points on two photograph with a real time precision control using epipolar line display.