How To Overlay Data For Track Day Videos with AEM Data Software

Most gearheads agree that track day videos are cool. You can share heroic in-car shots of yourself on YouTube bombing through the Corkscrew at Laguna Seca or you can show people how you jumped out of your racecar during a fire. Of course, not all track day videos are equal, and I have found the ones with vehicle data overlaid on them are much more dynamic and interesting to watch. To step up our own game of creating cool track day videos we decided to combine vehicle data and in-car video using hardware and software from AEM Electronics.

For collecting data in our 2019 Ford Fiesta ST autocross racer we use an AEM Electronics CD-5 Digital Dash Logger plugged into the OBDII port and suction cupped to the windshield.

Hardware & Software Required

We have been playing with our AEM Electronics’ CD-5LG Carbon Logging Display with Internal GPS all season long with our Ford Fiesta ST project car in the Way of the FiST series for Ford Muscle. Mostly we have been using it for its outstanding programmable shift light during autocross and rallycross events. But besides the gauges that the digital dash displays it is also collecting data about the vehicle through the OBDII port and GPS data from the antenna on the roof. We could use this data with videos.

Any action camera will work for overlaying data on videos. We use a GoPro Hero8 Black on a mount designed to attach to a vehicle’s headrest. This mount places the camera in the direct center of the vehicle to shoot through the windshield.

For videos I have been using GoPro products for years and recently upgraded to the Hero8 Black Edition. The Hero8 Black collects its own GPS data and can overlay vehicle speed using GoPro software, however, I have found that cameras mounted inside a vehicle don’t always collect GPS data and the camera itself doesn’t know what the vehicle is doing (RPM, temperature, etc.). So, we still use GoPro products for video, but for data information we will leave that to AEM.

Before you can start overlaying data on top of videos you need two things: data and video. Here you can see us using the AEM CD-5 Digital Dash Logger at an autocross to collect GPS data from a roof mounted antenna and vehicle data through the OBDII port. (Track photos by Brad Dawson.)

The best part of this project is going out and having some fun with cars to create a track day video. We headed to a local SCCA autocross using our AEM Electronics dash and went as fast as we could, sometimes on three wheels, and ended up winning the H-Street class that day. After the event was over we headed back home to download the video from the camera and the data from the digital dash. To access data from our AEM digital dash logger we use the free AEM Data software.

To get this process started you will need the software titled “AEM Data” which is a free download from AEM Electronics. This is a powerful tool to help you analyze the data collected from your vehicle.

Getting Started

The AEM Data software is a simple and free download from AEM Electronics. When you download it for the first time, during the installation wizard, remember to click the box to include the downloading of another software called “WebM Transcoder.” This will ensure you have an additional program you will need to convert your video files so they can be used with AEM Data. We will cover this more in depth in a few steps.

After you are done having fun on track you will need to download both your vehicle data from the AEM CD-5 and the video from your camera. We use a portable 12-volt power source to power up the AEM CD-5 for the download.

Once you have the AEM Data software on a laptop you will need to power up your AEM Digital Dash and use the USB cord to connect the dash with your laptop. This will allow the AEM Data software to download vehicle and GPS data from the dash. The whole process takes about twenty seconds.

To download the data from the AEM Digital Dash simply plug in the USB cord from the AEM CD-5 to a laptop computer, fire up the AEM Data software, go to the top menu bar, select “Logger” then pull down to “Download Log.” The computer does the rest.

Once you have a log to work with from the AEM Digital Dash, you won’t see anything interesting on the screen. You will need to go to the top of the menu bar, select “Add” and then in the drop down menu select “Channels.” This will show you all of the different channels which were logged during your time at the track. We use the engine speed channel to show RPM. This “Add” option will also allow you to add a track map and a video screen.

This drop down menu allows you to add a number of views to your screen. The ones you will need are the Channel, Track, and Video.

Before you can add a video to the screen you will need to convert that video file to something called a WEBM video. If you aren’t a video editing nerd this probably doesn’t mean much to you. Good news, AEM made this easy with their WebM Transcoder software. You don’t need to be an expert at Adobe Premiere video editing software to make this work. AEM gets it, you’re a racecar driver, not Steven Spielberg.

This WebM Transcoder software is free from AEM and can be installed when you initially install your AEM Data software. You simply drop in your video file from your action camera and it converts the file to a WEBM file which can be used in the AEM Data software.

The video file has to be converted from whatever it originally started as from the camera – MP4, WMV, AVI, etc. – to a WEBM file. Using the WebM Transcoder software it simply converts digital video files to WEBM files so the AEM Data program can use them. This can be a time consuming process, so have some patience (it may take up to 30 minutes). Pro tip: edit your total video down to just what you want (like a single lap) to shorten up this process.

Here you can see I have three screens open on my AEM Data software. I added a Channels screen (engine data), a Track screen (GPS data) and a Video screen (GoPro data).

Setting Up Your Overlays

Once your video is converted to WEBM you can add a video screen and you will see your video displayed in the software. On our screen we have three things added: Channel, Track, and Video. By hitting the play button at the top of the screen you will see all three screens move according to the data. You will see the engine data start to move (RPM go up), you will see the white ball on the track map begin to move (GPS data), and you will see the video play. Right away you will realize the video and the GPS/engine data are probably out of sync.

The video and the data file will both start from zero, which generally is never the same moment in time. You will need to synchronize the video with the data by delaying the start of either one.

You can see in the photo above that I delayed the start of the data log by 2 hours, 57 minutes and 44 seconds to match the beginning (zero time) of the video log. My vehicle data log was very long (I had multiple events on it), which is why I had to put in so much delay to synchronize my video. Pro tip: download and clear the logs in the AEM Digital Dash after every event. I used an RPM spike in the data to determine the exact moment I left the starting line. You can also see the flagger is waving the green flag at the same moment. It is go time.

To add gauges to overlay on your video simply right click over the video screen. When the menu pops up, select Add Gauge and then pick the gauge you want. For our setup we used: Bar (for throttle %), Image (for a DNN Motorsports logo), Number (for vehicle speed), Tacho (for RPM), and Track (for a GPS track map).

Adding different types of gauges over your video is extremely easy with the AEM Data software. By simply scrolling your mouse over the video, right click, then select Add Gauge, which gives you an additional drop down menu with lots of choices. The options here are pretty limitless. It is in this “Add Gauge” section where you can add a team logo (we added ours for Team Double Nickel Nine Motorsports) by adding an Image. We added a bar graph to show throttle percentage. We added a track map to show where we are on track during a lap. We added a tachometer to show engine speed. We also added a number gauge to show vehicle speed.

Once you have a gauge on your screen, click on the graphic to select it, then right click to view the Gauge Configuration options. Here we have selected our Number gauge and then using the Channel menu we assigned that number to the GPS Speed channel from the vehicle. And with that we had vehicle speed displayed.

The next step to making your gauges work is assigning a channel to them. For the tachometer we assigned that to the engine speed channel. For the throttle percentage we assigned that to the throttle channel. For vehicle speed we assigned that to GPS speed (we could have chosen vehicle speed from the OBDII data but that wouldn’t account for wheel slip). The gauges can be manipulated widely depending on what you want to do with the data. You can move the gauges anywhere you want on screen and adjust their size. You can change font size, color, and you can make the background of a gauge transparent. I found that just playing around with the options really helped me learn the abilities of the software and what I wanted to see on screen.

If you have the layout you are looking for it is time to render your video. Right click over the video screen and select Encode Video. Here you will have the option to save the video to a specific location and to render the whole video or just a selection of the video. We recommend just rendering the selection (the section of the lap you have highlighted).

The whole point of all this work is to end up with a cool video at the end. So, after you have your video synched with your data and you have all the gauges you want to see overlaid on your video it is time to encode the video so you can watch it on the big screen. Right click on the video and choose Encode Video. I choose Best Quality and I choose to only render the section of video I want to see (not the entire file from my GoPro). Nobody needs to see me idling in the pits for five minutes. Boring stuff.

The processing time for the video takes a few minutes so patience is your friend here. But once it is completed the video is ready to view.

Once our video was encoded it was time to find where I told the software to save it on my hard drive and check it out. The video came out great and more importantly it taught me something about my driving style. I need to be smoother with the throttle pedal. According to the bar graph on the video, I am using the throttle pedal like a light switch: on or off. It is only because of the data overlay on the video that I was able to self-reflect and try to improve my driving. Using the AEM Electronics hardware and software didn’t just create a cool track day video, it also is helping me to go faster around the track. Win-win!

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About the author

Rob Krider

Rob Krider will race absolutely anything. He is a multi-national champion racing driver and is also the author of the novel, Cadet Blues.
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