Introduction to Pix4D Software and 3D Model Data Collection Methods

 We will begin to work with software that is used to process data gathered during UAS mapping missions into formats that can be used in GIS and other forms of Remote Sensing software.

Introduction to Pix4D:

    It's important to understand the software before you use it to understand its full capabilities. Pix4D has its own help page that provides information on how to use the software. We are going to explore the help documentation/online support.

               

               Figure 1: Pix4D help menu

The video academy has video tutorials that shows how to do different things, a few examples include:

• Adding a new lens to your camera and you need to change the camera model
• https://youtu.be/tY0n_61rOts

• Automated DTM generation and contour lines
•  https://youtu.be/NjCiTHTKXr8

• You want to do Point Cloud editing 
• https://youtu.be/N1kBU4Ethp4

The top portion of the online software manual also allows you to search for specific topics

Figure 2: Manual search bar

Truck 3D Model in Pix4D

We were provided with a data set that contained images from different angles of a pickup truck parked in the parking lot. It is important to take note of the image acquisition pattern, it looks like a circle around the object we are trying to make a model of. The pattern would look like this because you want to capture all sides of the object. You need to have complete 360 coverage of the object.

Figure 3: Acquisition Pattern of Truck Model

Figure 4: NADIR view of 3D Model

Figure 5: Right side view of 3D Model

Figure 6: Left side view of 3D Model

    Once the project was finished, the 3D model had the highest quality from a NADIR view (Figure 4). The worst quality was from a side view of the truck (Figure 5-6). This is because most of the images were from a top-down view so when the images were processed, the images looking straight down helped to make the model have better quality. 

    There are differences in quality because of where the photos were taken. There weren’t any photos directly on the side of the truck, but there were plenty of photos from a top-down view. Therefore, there was better quality from the top and not the side. To better gather the data, you would want to fly a grid pattern directly over the object NADIR. Then also capture images from around the object at a few different angles. This will help ensure your 3D model looks complete.