🚀 STM32 NeoPixel POV Light Painter

A high-resolution Persistence of Vision (POV) light painting stick built with an STM32F103C8T6 (Blue Pill) and a 144-LED WS2812B strip.

🌟 Result

Original Image	Light Painting Result

🛠 Technical Specifications

• Microcontroller: STM32F103C8T6 (ARM Cortex-M3)
• LED Density: 144 Pixels per meter (High Resolution)
• Color Correction: 2.8 Gamma LUT (Lookup Table) for realistic photo reproduction.
• Timing: ~28ms per column delay for a steady 5-second "painting" sweep.
• Communication: Driven via FastLED library on Pin PB15.

🧠 How It Works

1. Image Conversion

The provided converter.py Python script uses the Pillow library to resize images to 144 pixels in height and convert them into a 1D const uint8_t C-array.

2. Gamma Correction

To prevent colors from looking "washed out" in long-exposure photography, the firmware applies a Gamma 2.8 correction curve. This ensures that the deep reds and greens of the flags appear saturated and natural on the camera sensor.

3. Persistence of Vision (POV)

By flashing one vertical column of pixels at a time while moving the stick horizontally, the human eye (or a camera shutter) perceives a complete 2D image "floating" in mid-air.

📂 Project Structure

• /src: STM32 source code (PlatformIO/Arduino).
• /tools: Python image-to-header converter.
• /include: Generated image_data.h files.

🔧 Setup & Installation

1. Convert Image: Place your image in /tools and run python converter.py.
2. Flash MCU: - Set BOOT0 jumper to 1.
   • Connect via CP2102 (UART1: PA9/PA10).
   • Upload via VS Code/PlatformIO.
   • Set BOOT0 back to 0 and Reset.
3. Capture: Use a tripod and a smartphone with Manual/Pro Mode (Shutter: 8s, ISO: 100).