Geovis Project Assignment @RyersonGeo, SA8905, Fall 2019
The City of Toronto Police Services have been keeping track of and stores historical crime information by location and time across the City of Toronto since 2014. This data is now downloadable in Excel and spatial shapefiles by the public and can be used to help forecast future crime locations and time. I have decided to use a set of data from the Police Services Data Portal to create a time series map to show crime density throughout the years 2014 to 2018. The data I have decided to work with are auto-theft, break and enter, robbery, theft and assault. The main idea of the video map I want to display is to show multiple heat density maps across month long intervals between 2014 to 2018 in the City of Toronto and focus on downtown Toronto as most crimes happen within the heart of Toronto.
The end result is an animation time-series map that shows density heat map snapshots during the 4-year period, 3-month interval at a time. Examples of my post are shown at the end of this blog post under Heat Map Videos.
All datasets were downloaded through the Toronto Police Services Data Portal which is accessible to the public.
The data that was used to create my maps are:
- Auto Theft
- Break and Enter
Process Required to Generate Time-Series Animation Heat Maps
Step 1: Create an additional field to store the date interval in ArcGis Pro.
Add the shapefile downloaded from the Toronto Police Services Portal intoArcGIS Pro.
First create a new field under View Table and then click on Add.
To get only the date, we use the Calculate Field in the Geoprocessing tools with the formula
where Occurrence is the existing text field that contains the 10 digit date: YYYY-MM-DD. This removes the time of day which is unnecessary for our analysis.
Step 2: Create a layer using the new date field created.
Go into properties in the edited layer. Under the time tab, place in the new date field created from Step 1 and enter in the time extent of the dataset. In this case, it will be from 2014-01-01 to 2018-12-31 as the data is between 2014 to 2018.
Step 3: Create Symbology as Heat Map
Go into the Symbology properties for the edited layer and select heat map under the drop down menu. Select 80 as its radius which will show the size of the density concentration in a heat map. Choose a color scheme and set the method as Dynamic. The method used will show how each color in the scheme relates to a density value. In a Dynamic setting versus and constant, the density is recalculated each time the map scale or map extent changes to reflect only those features that are currently in view. The Dynamic method is useful to view the distribution of data in a particular area, but is not valid for comparing different areas across a map (ArcGIS Pro Help Online).
Step 4: Convert Map to 3D global scene.
Go to View tab on the top and select convert to global scene. This will allow the user to create a 3D map feature when showing their animated heat map.
Step 5: Creating the 3D look.
Once a 3D scene is set, press and hold the middle mouse button and drag it down or up to create a 3D effect.
Step 6: Setting the time-series map.
Under the Time tab, set the start time and end time to create the 3 month interval snapshot. Ensure that “Use Time Span” is checked and the Start and End date is set between 2014 and 2018. See the image below for settings.
Step 7: Create a time Slider Steps for Animation Purposes
Under Animation tab, select the appropriate “Append Time” (the transition time between each frame). Usually 1 second is good enough, anything higher will be too slow. Make sure to check off maintain speed and append front before Importing the time Slider Steps. See below image.
Step 8: Editing additional cosmetics onto the animation.
Once the animation is created, you may add any additional layers to the frames such as Titles, Time Bar and Paragraphs.
There is a drop down section in the Animation tab that will allow you to add these cosmetic layers onto the frame.
Animation Timeline by frames will look like this below.
Step 9: Exporting to Video
There are many types of exports the user can choose to create. Such as Youtube, Vimeo, Twitter, Instagram, HD1080 and Gif. See below image for the settings to export the create animation video. You can also choose the number of frames per second, as this is a time-series snapshot no more than 30 frames per second is needed. Choose a place where you would like to export the video and lastly, click on Export.
As this was one of my first-time using ArcGIS Pro software, I find it very intuitive to learn as all the functions were easy to find and ready to use. I got lucky in finding a dataset that I didn’t have to format too much as the main fields I required were already there and the only thing required was editing the date format. The number of data in the dataset was sufficient for me to create a time series map that shows enough data across the city of Toronto spanning 3 months at a time. If there was less data, I would have to increase my time span. The 3D scene on ArcGIS Pro is very slow and created a lot of problems for me when trying to load my video onto set time frames. As a result of the high-quality 3D setting, I decided to use, it took couple of hours to render my video through the export tool. As the ArcGIS Pro software wasn’t made to create videos, I felt that there was lack of user video modification tools.
Heat Map Videos Export
- Theft in Downtown Toronto between 2014-2018. A Time-Series Heat Map Animation using a 3 month Interval.
- Robbery in Downtown Toronto between 2014-2018. A Time-Series Heat Map Animation using a 3 month Interval.
- Break and Enter in Downtown Toronto between 2014-2018. A Time-Series Heat Map Animation using a 3 month Interval.
- Auto Theft across the City of Toronto between 2014-2018. A Time-Series Heat Map Animation using a 3 month Interval.
- Assault across the City of Toronto between 2014-2018. A Time-Series Heat Map Animation using a 3 month Interval.