Creating Your BS4TV Video

Using BS4TV GlyphThis tutorial will lead you through the basic process of creating your BS4TV track video. You'll find this to be quite easy and a simple, and short, drag race video can can be finished in 10 -15 minutes, plus however long you spend in the final editing using your favorite video editing software.

The procedure described here covers only the high points. It will give you an idea of what the working concepts are and what the basic workflow is. Be sure to spend a little more time with BS4TV to discover many more of the features it offers.


  1. Export Your GTech Data from the PASS Software
  2. Import the GTech Data into BS4TV
  3. Augment Your GTech Pro Data
  4. Set Up the Blue Screen
  5. Set Up the Replay
  6. Record the Replay
  7. Merge the Blue Screen and Track Videos


Under construction. Updated screen shots are needed.

1. Export Your GTech Data from the PASS 2.0 Software

After reviewing your data using the GTech Pro's PASS software and entering your lap times and other information, export the main run as a *.csv (comma-separate values) file.

PASS will automatically determine the trap times for drag race runs, but for road race sessions you'll need to enter your lap times in PASS, otherwise, BS4TV will think it is all one lap.

Screen shot of the PASS software
Screen shot of Tesla's PASS 2.0 software.

Back to top

2. Import the GTech Data into BS4TV

Import your data (the PASS-exported csv file) into BS4TV. BS4TV will automatically determine if the data were from a road race or drag race session and will configure itself accordingly.

During the import BS4TV will reanalyze the data, determine the time-slip values and other results (maximum power and torque, etc.) for drag race sessions and various performance results (maximum G's, average, min, and maximum lap times, etc.) for road race sessions.

BS4TV, Road Race Laps
BS4TV's laps display (road race mode)

Back to top

3. Augment Your GTech Pro Data

With the data imported and the default analysis completed, it is time to enter additional information about your car, such as the aerodynamic drag coefficients and frontal area, gearing, tire size, and other items that will let BS4TV perform a more thorough analysis of your session and will make it possible to provide a more accurate estimate your speed, power, and other results. The most important of these, as far as making your video goes, are the estimates of speed and distance.

BS4TV offers two methods for estimating your car's speed. One is based only on the accelerometer data, and the other one the RPM data combined with information about your car's gearing and tire size. Both methods work very well for short drag race runs, but for longer road race runs, especially at tracks that include a lot of elevation changes, the RPM method will work better. To use the RPM method you simply enter the number of the gear you are shifting into at points in the data where the shift occurred. These shifts are easy to locate on the RPM and G's versus time chart (see the figure below). If you enter a 0 for the gear BS4TV will switch back to using the G's method. You would normally do this to tell BS4TV that you are shifting, the clutch pedal is depressed, wheels are spinning, anything that causes engine RPM to no longer be related to the car's speed.

The screen shot below shows the RPM plot from Mike Smith's drag race run, wheel spin and all. It is pretty easy to see where he lifted, shifted, and where his wheels were spinning. The situation for road race runs is much the same except that there are many more shifts and the session is longer.

BS4TV, Drag Race
BS4TV's drag race run display (drag race mode)

Back to top

4. Set Up the Blue Screen

BS4TV offers two screen styles, a dial gauge style and a bar gauge style, and the gauges shown are slightly different for drag race and road race modes. Both include tachometers, but the speed is only displayed in drag race sessions while the longitudinal and laterals G's gauges are used in road race sessions.

Select the style you want to use, then select the screen size, and the screen color. Blue screens are commonly used, but if you want to use blue in your screens, then use a green screen instead.

Once you have the screen you want, right-click the gauges and text panels and a properties form will pop up. Change the properties as you like and close the form and the new settings will be applied.

Samples of available screen styles are shown below.

BS4TV Screens
Examples of BS4TV screens.

Back to top

5. Set Up The Replay

Now that the data are loaded and the screen is ready, there are a few last minute things to do to get the replay ready.

The header and footer text can be changed automatically during the replay. You simply enter the new text and a simple command (+H or -H to display or clear text in the header, for instance) in the script table.  BS4TV will automatically put your lap times and drag run marks in this table, but you can also add other messages.

You might want to define a time offset so that a time of 0 seconds is displayed when you first cross the start/finish line (road racing mode) or you launch in a drag race. BS4TV will display a time of "-.-- seconds" for drag race mode or "-:--.--" for road race mode, up to the point where a time of 0 seconds is reached. Afterwards, the time displayed will reflect the actual time of your session or run, not the time the GTech was logging the data.

Everything is now ready for replay, but before doing that, save your settings. That way you can use them again for other projects.

Back to top

6. Replay and Record Your Data

To start, stop, step, pause, and rewind the replay just use the VCR-style controls located below the screen. You can start the replay and record separately, for example, to let you create a short leader for the video.

During the replay you can monitor the progress of the recording, the number of frames, number of dropped frames and disk space available.

BS4TV will stop recording as soon as the replay is done.

BS4TV Replay Panel
BS4TV's Replay Panel

Back to top

7. Merge Your Blue Screen and Track Videos

Merging your new blue screen video and track video is done using third-party video editing software such as Adobe Premiere, Final Cut Pro, and others. There are a separate tutorials here that cover this in some detail so I'll refer you to those. But, for completeness, here is a brief overview - import both videos, place the blue screen track above the track video track, then apply the blue screen (chroma-keying) effect to the top track. This will make the blue areas transparent and the dark blue areas dark. The non-blue text and gauges will still be visible. Export this video and you are done.

Back to top