psfv (Pitch Speed From Video) is a simple tool to estimate the speed of a
pitched softball or baseball from a video clip (i.e., one that was taken using a
cell phone's camera), without using more accurate equipment such as
PITCHf/x or a radar gun.
The psfv tool computes the average velocity v of a pitched ball, using
the simple formula
v = d / t
where d and t are the distance and duration, respectively, from the ball
leaves a pitcher's hand until it is above the home plate. Note that our estimate
is different from and slower than the MLB velocity
(VELO), which is defined to be
"the maximum speed of a given pitch at any point from its release to the time it
crosses home plate" (effectively the speed of the ball at the release point due
to physics).
Currently, only softball pitch speed estimation is supported. Baseball support will be added in the future.
psfv depends on ffprobe, which can be obtained by installing ffmpeg.
On macOS
brew install ffmpegOn Ubuntu 24.04 LTS
sudo apt install ffmpegInstall psfv
go install github.com/syncom/psfv@latestBefore AI can help us do better, one needs to do the video clip preparation step manually. The manual work here isn't too difficult, yet needs to be performed carefully.
To obtain the input video clip for psfv, load your game footage into a video
editor supporting video trimming at the frame level. For example, QuickTime
Player for
Mac
can be used to do this. Carefully trim the video so that the resulting clip
starts at the frame when the ball is released from the pitcher's hand, and end
at the frame when the ball crosses the home plate. The duration of the video
clip should be less than 1 second in practical scenarios. A sample prepared
video clip is pitch_sample_10u.mp4
For softball 10U
$ psfv softball --age-group 10u testdata/pitch_sample_10u.mp4
Duration of video: 0.636003
Age group: 10u
Average pitch speed: 33.233119 mph (53.483388 kph)Please refer to psfv --help and psfv softball --help for more usage detail.