Processing Image Data In Pix4D

Assignment Introduction:

What is Pix4D?  What Products does it generate?

Pix4D is a popular software that is used to generate point clouds from UAS data. It utilizes GCPs and photgrammetry to create point clouds and DSMs.

Why is it so integral to UAS data processing?

Pix4D is so integral in processing UAS data because it produces DSMs from simple pictures, this DSM is the baseline for all other processing.

Assignment Methods:

The first step in processing an image in Pix4D is initial processing of the images. This will report a quality report that is integral in the accuracy of further processing. You perform ONLY the initial processing first because the next two steps (point cloud and orthomosaic) take a long time to process, so if your initial report comes back with bad data, you do not have to waste time processing the next two steps. Figure 1 shows an example of a quality report. Take note of the processing time.

Figure 1. Initial Processing Quality Report

Some of the things the quality report checks for is georeferencing, pixel matching, and camera settings. After confirming your data is correct in the quality report, you can continue with point cloud processing. Figure 2 shows the final point cloud.

Figure 2. Final Point Cloud

When dealing with Pix4D data, the number out outputs can become confusing. That is why it important to have a proper file system. An ideal system would have 3 separate folders for collection, processing, analysis with metadata placed in the master folder. Figure 3 shows an example of this file naming convention. 

Figure 3. Correct File Naming System

After the DSM has been created from the point cloud, the next step was to create a deliverable product that was easy to consume for the customer. This was done by creating a video of the actual DSM itself. To do this, you needed to chose the trajectory point in the DSM, figure 4 shows the video trajectory points that were created. An actual video of the DSM can be found in the figures page of this portfolio. 

Figure 4. Trajectory Points 

The DSM created in this assignment is similar to the one used in Lab #3, the difference is that this DSM did not utilize GCPs. This allowed for not accurate elevation values as shown in figure 5.

Figure 5. Comparison of DSMs with or without GCPs

Assignment Conclusions:

Pix4D is important in processing UAS data because it takes the pictures that are taken by a drone, and processes them into manipulated DSMs and point clouds. this, however, takes alot of time to get accurate results if trying to process a large area, for example, if trying to process a folder of 6000+ images, it could take upwards of 24 hours depending of how accurate you want the DSM. 

Building Maps with UAS Data

Assignment Introduction: 

Why are proper cartographic skills essential in working with UAS data?

Cartographic skills are essential because when trying to convey information to clients, they should be able to read your data easily.

What are the fundamentals of turning either a drawing or an aerial image into a map?
  
To be able to turn an aerial image into a map, you need to add a scale. Typically other elements such as a legend or locator map are also vital to making a map.

What can spatial patterns of data tell the reader about UAS data? Provide several examples.

It can show the reader details about the map that a picture cannot show. An example of this would be: hillshading, slope, aspect, population density. 

What are the objectives of the lab?

The objectives of this lab are to simulate turning UAS data into deliverable maps that show different analysis functions in ArcPro.

Assignment Methods:

What key characteristics should go into folder and file naming conventions?

Important information, such as the location and what the file is, should be located in file naming conventions, the folder naming convention should be similar but should contain all the required items inside one folder so you can easily copy and paste the whole project with one click.

Why is file management so key in working with UAS data? How does this relate to the metadata?

File management is so important because typically in UAS you are dealing with a large amount of files. When you have a proper file management system, this can help eliminate confusion when dealing with certain files. Metadata helps because it contains basic information that can help you identify which files you are working with.

What key forms of metadata should be associated with every UAS mission?

UAS metadata should include basic information about the flight, such as: sensors, location, date flown, UAS platform. Figure 1 shows an example of UAS metadata.

Figure 1. UAS metadata

What basemap did you use? Why?
 
I used the default topographic map because it shows high contrast to when the DSM was added. It clearly shows where the subject area is. Figure 2 shows the Wolf Creek DSM being added onto the topographic map. Note how you can clearly see where the subject area is.

Figure 2. DSM of Wolf Creek

What is the purpose of the "pyramid" and "calculate statistics" commands?

The pyramid command will essentially group pixels together as you zoom out and vice versa as you zoom in. This allows raster data to be easily zoomed in and out. The calculate statistics command will analyze your raster data to find elevation extremes and cell size

Why might knowing Cell Size, Units, Projection, Highest Elevation, Lowest Elevation be important?

If you know the elevation extremes and cell size, this allows you to accurately know the size of the subject area that you're using. The elevation extremes allow you to create a slope analysis of areas which are useful in industry for multiple reasons. Figure 3 shows a slope analysis of Wolf Creek.

Figure 3. Slope Analysis of Wolf Creek

What is the difference between a DSM and DEM?

A DSM contains elevation values of everything on the surface, trees, buildings, while a DEM exclusively shows the terrain elevation with the trees and buildings removed. Figure 4 shows a DEM while Figure 5 shows a DSM. Note how the DSM has trees.

Figure 5. DSM

Figure 4. DEM

What does hillshading do towards being able to visualize relief and topography?

Hillshading adds shading to the DSM with respect to an angle of light. It can be combined with a regular DSM to create an appealing map that shows elevation with shading. Figure 6 shows a hillshaded DSM.

Figure 6. Hillshaded DSM of Wolf Creek

How does the orthomosaic relate to what you see in the shaded relief of the DSM?

The shaded relief really helps you visualize the orthomosaic. The orthomosaic only shows the ground but cant really help show the elevation of the terrain. Figure 7 shows the orthomosaic of Wolf Creek, note how Figure 6 and Figure 7 combined really allow you to visualize the space.

Figure 7. Orthomosaic of Wolf Creek

What benefits does hillshade and 3D view provide? How might this relate to presenting this information to a client/customer?

A 3D view was also generated, this could help the customer see an object in the subject area from different angle. The blue color ramp shows the features very well while still contrasting the high and low elevations. Final map layouts can be viewed in the Maps, Tables, and Figures section of this blog under Lab 3.


Assignment Conclusion: 

Summarize what makes UAS data useful as a tool to the cartographer and GIS user?

UAS data is useful to cartographers and GIS users because it allows them to do many different things with the subject area. without the extra work of having to walk across the whole area collecting data.

What limitations does the data have? What should the user know about the data when working with it?

The limitations with UAS data is that it can not gather data from under canopies very accurately. The user should know whether or not they are dealing with a DSM or DEM.

Speculate what other forms of data this data could be combined with to make it even more useful?

The data in this lab could be combined with regular pictures on the ground of the specific slopes for better visualization of the DSM.

Getting to Know ArcPro

Assignment Introduction: 

What makes data geospatial? That is, what makes the data you worked with today geospatial in nature (think coordinates)?

Geospatial data is data that uses vectors and rasters to show how humans interact with the environment around them.

What makes data in a GIS different than a digital map?

Data in GIS uses coordinate systems to make a map but a regular digital map is essentially just a picture.

Why is having an understanding of geospatial concepts and geospatial data so fundamental to working with UAS data?

If you do not understand geospatial concepts, you wont be able to effectively portray/process UAS data.

What are some of the key geospatial concepts and fundamentals that this lab addresses?

This lab addresses the basics of how you can change the symbology of certain layers as well as the way they interact with the basemap. You learn how to make a simple project using ArcPro.

Fig 1. Interaction between base map, cities, and eco-region. 

Assignment Methods:

The goal of this assignment was to simulate creating a visual project to show the effects of a proposed road design through Rondonia. The data was gathered by various methods but should all be put onto one "poster" that could be presented to an audience. To do this effectively, the layers of the map should work together to communicate how much of the surrounding forest has to be cut down. This was done by using the analytical tools in ArcPro to calculate how much square kilometers of forest would be cut down. To make the poster more digestible, a scale and map key were added.

Fig 2. Rondonia border and major cities.

The first step was to use the borders to highlight Rondonia and all the populated cities. The symbology needed to be changed so that you could see the underlying imagery basemap. This was done by making the border a high visible color and making the infill transparent. The basemap was also change to an imagery map instead of a topography map such as the one in Figure 1.

The next step was adding other map elements. Minor roads, major roads, deforested areas, and the protected forests. All the symbology of these elements were changed so that they can be viewed easily. Figure 3 shows the map with all the above mentioned elements.

Fig 3. Rondonia major roads, cities. Protected forests are in green.

After having a good base for the map, the proposed road needed to be added. The image of the proposed road was a raster data type, to make this more editable, the raster image needed to be "changed" to a vector data type. To do this, the trace function was used to create a line that is approximately the same dimensions of the proposed road. Figure 4 shows the proposed road vector image.                                                                                

Fig 4. Raster image of proposed road.

After the trace was completed, one of the analysis tool was used to create an perimeter around the proposed road. Another tool was then used to calculate the area inside the perimeter. This is the area that would need to be deforested. Figure 5 shows the proposed road with the deforested area highlighted an approximate area that would need to be deforested.

Fig 5. Proposed road with the approximate at-risk area

Once the area was highlighted, the last step was to clean the rest of the project, changing colors and adding other elements such as: the title, scale, map key, and globe to highlight the project area. Figure 6 shows the final iteration of the poster. 

Fig 6. Deforestation in Rondonia

Assignment Conclusion: 

Summarize how ArcPro is a GIS software. What makes it stand out?

ArcPro is a GIS software because it uses coordinate systems, what stands out is that it has a ton of useful analytic tools that allow you to do many things with the geospatial data you collect. 

We talked about all the issues that can come up when working with UAS data in a GIS. After this intro to the software, reflect on how its complexity could create problems with using UAS data.

  

One potential issue that could arise is not using the correct coordinate system, or data type. This tutorial showed how to essentially use raster data to make vector data. 

Speculate how the data you worked with in this tutorial could be supplemented with UAS data.

If the data used in this lab was UAS data, it would have to be in a much more centralized area, but the main concepts could be applied. The data would just be collected via drone instead of satellite. 

A Post About Me

Assignment Summary: 
In this section of your first e-portfolio post, I want to see the following: what background do you have with UAS, what led towards your interest in UAS, what do you want to do as a career with UAS, now summarize what you wrote in your first post and put that into your about me page.



What background do you have with UAS?
My background in UAS prior to college is mainly limited to recreational flying of DJI phantoms. I used this drone to take and edit videos and photos for fun. Here is an example of my work:

What led towards your interest in UAS?
As a child I was always obsessed with RC vehicles: cars, boats, helicopters. This interest led me into the realm of aerial photography, this made me wonder about what other things could be done with these wonderful tools, so I decided to pursue a career in UAS.

What do you want to do as a career with UAS?
An ideal career path for me in UAS would be a systems or design engineer in a UAS company. I have also considered starting my own UAS consulting company; designing and piloting drones with specific uses.

A Critique of Previous e-Portfolios

Assignment Summary:
Write a critique of 5 different student E-Portfolios, take note of what you think is good, and what is lacking. Summarize what you read in terms of how you intend to approach your E-Portfolio in terms of content and format. Also comment on how you see the UAS curriculum and E-Portfolio content evolving through time.

Portfolio #1 - Krysta Rolle, AT 419 Spring 2019
I personally like that the first page when visiting this blog has a beautiful picture of a drone through a snowy mountain. The shortcomings that this blog has is that there are very few pages, it almost feels as if its just one continuous page of blog posts.

Portfolio #2 - Ryan Ferguson, AT 419 Spring 2019
One thing about this page that caught my eye is that it is very simple, and all the blog posts have a picture included with them. One thing that I think can be improved upon is more generalized header links, the ones that are used are very specific which can cause harder navigation through the blog page.

Portfolio #3 - Evan Hockridge, AT 419 Spring 2019
This e-Portfolio has a few things that I do not like, the first being its color scheme. The black makes it seem not very professional. There is also a wall of text on the home screen, using a few pictures would make this portfolio much easier to view.

Portfolio #4 - Todd Horn, AT 419 Spring 2019
Todd's e-portfolio looks very good. I like the way he has a nice picture in the background as well as the way the posts are separated by weeks. My only problem is that the sidebar directory names are in a different order as the names up top.

Portfolio #5 - Ian Wiley, AT 419 Spring 2019
Ian's blogger site has a few issues, I think that the name of the blog itself is unprofessional. The picture slideshow on the homepage also has very low resolution pictures which looks bad. It does have some redeeming qualities, if you scroll down on the homepage, I like the way that the posts are organized in a grid.

Summary:
After reviewing the previous e-Portfolios, I intend to take a very structured and professional approach to my e-Portfolio. I intend for the content posted on this portfolio to show what knowledge I learn during this whole process as well as showcase the projects and data we complete during the process. The UAS curriculum seems to evolve to a more research focus as time goes on. The e-portfolios reflect this by including more graphs, tables and capstone posters.