FPS

The tagged release of fortio.org/terminal/ansipixels used to also includes this standalone binary, fps, which tests your terminal frames per second capabilities.

Note: FPS used to be just a directory in fortio/terminal but had to be broken away to avoid a loop with its use of fortio for stats, and unfortunately the otherwise excellent goreleaser non pro doesn't let you just have a sub go.mod, so I moved it here while preserving the old path thanks to fortio.org meta tags

See the source fps.go

You can get the binary from releases

Or just run

CGO_ENABLED=0 go install fortio.org/terminal/fps@latest  # to install or just
CGO_ENABLED=0 go run fortio.org/terminal/fps@latest  # to run without install

or even

docker run -ti fortio/fps # but that's obviously slower

or

brew install fortio/tap/fps

Use the -image flag to pass a different image to load as background. Or use -i and fps is now just a terminal image viewer (in addition to keys, you can now zoom using the mousewheel, click to move the image - see ? for help).

Pass an optional maxfps as argument.

E.g fps -image my.jpg 60 will run at 60 fps with my.jpg as background.

After hitting any key to start the measurement, you can also resize the window at any time and fps will render with the new size. Use q to stop.

Image viewer screenshot:

Detailed statistics are saved in a JSON files and can be visualized or compared by running fortio report

Hot (!) off the press a new -fire mode for fps (with space to toggle on/off and i to turn off the text):

Web serving fire mode

There is also now a web mode, using -http :3000 for instance, serves the doom fire mode on /fire on that port, eg

fps -n 100 -http :3000 20 # 20 fps, 100 frames served
curl localhost:3000/fire  # or add ?colors=256 if the terminal doesn't support truecolor

You can demo it on

curl --compressed https://demo.fortio.org/fire
# or if your terminal only supports 256 colors (like apple terminal)
curl --compressed "https://demo.fortio.org/fire?colors=256"

Usage

Additional flags/command help:

fps 0.27.0 usage:
        fps [flags] [maxfps] or fps -i imagefiles...
or 1 of the special arguments
        fps {help|envhelp|version|buildinfo}
flags:
  -color
        If your terminal supports color, this will load image in (216) colors instead of
        monochrome (default true)
  -fire
        Show fire animation instead of RGB around the image
  -gray
        Convert the image to grayscale
  -http port
        Listen port, eg :3000, empty for normal CLI interactive mode
  -i    Arguments are now images files to show, no FPS test (hit any key to continue)
  -image string
        Image file to display in monochrome in the background instead of the default one
  -n number of frames
        Start immediately an FPS test with the specified number of frames (default is
        interactive)
  -nobox
        Don't draw the box around the image, make the image full screen instead of 1
        pixel less on all sides
  -nojson
        Don't output json file with results that otherwise get produced and can be
        visualized with fortio report
  -nomouse
        Disable mouse tracking
  -truecolor
        If your terminal supports truecolor, this will load image in truecolor (24bits)
        instead of monochrome