terminalcam

Real-time ASCII art webcam renderer for the terminal. Captures live webcam input via OpenCV and renders it as ASCII characters using LUMA-weighted brightness mapping.

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Prerequisites

brew install opencv

Build & Run

make
./terminalcam

On first run, macOS will prompt for camera access -- grant it.

Controls

Key	Action
q	Quit
b	Decrease brightness
B	Increase brightness
i	Invert (toggle light/dark)
f	Toggle FPS display
^C	Quit

How It Works

Each frame from the webcam is divided into a grid of rectangular blocks sized to fill the terminal. Each block's average color is converted to brightness using the LUMA formula:

brightness = 0.299 * R + 0.587 * G + 0.114 * B

The brightness value (0-255) maps to a position in a 70-character ASCII ramp from light to dark:

 .'`^",:;Il!i><~+_-?][}{1)(|/tfjrxnuvczXYUJCLQ0OZmwqpdbkhao*#MW&8%B@$

The image is flipped horizontally for a mirror effect. Terminal character cells are taller than they are wide (~2.2:1), so block height is scaled accordingly to preserve aspect ratio.

Rendering uses ANSI cursor-home (\033[H) instead of screen-clear to eliminate flicker, with the entire frame written in a single write() call.