📸 Photo Booth 🖨️

Tap. Snap. Print. ✨
Instant thermal receipt photos from a repurposed POS terminal

---

🎉 What is this?

A tiny app that turns a Sunmi V2 POS terminal into a fun photo booth! Take a photo and it prints instantly on the built-in thermal receipt printer as a gorgeous dithered black-and-white print. 🖤🤍

Think retro polaroid vibes, but on a receipt. 🧾✨

---

🕹️ How to use

1. 👀 Look at the screen — full camera preview
2. 👆 Tap anywhere — countdown starts: 3... 2... 1...
3. 📸 Flash! — photo captured
4. 🎨 Magic happens — your photo gets dithered into beautiful black & white dots
5. 🖨️ Brrrrr — out comes your photo on thermal paper!
6. 🔄 Ready for the next one!

---

🤏 How small is it?

2.9 MB. That's it. Smaller than a single selfie.

• 📷 Camera? Built-in Android API. Zero libraries.
• 🎨 Dithering? Pure math. ~80 lines of Kotlin.
• 🖨️ Printer? One tiny Sunmi library.
• 📁 Files on disk? None. Everything lives in memory.

---

🛠️ Build & Run

cd photo-booth
./gradlew assembleDebug
adb install app/build/outputs/apk/debug/app-debug.apk

Or over WiFi! 📡

adb connect 192.168.1.85:5555
adb -s 192.168.1.85:5555 install -r app/build/outputs/apk/debug/app-debug.apk

---

🖼️ The Science of Receipt Art

Your photo goes through Floyd-Steinberg error diffusion — the same algorithm used in newspaper printing since the 1970s. It spreads the "error" of turning a gray pixel into pure black or white across its neighbors, creating an illusion of smooth gradients using only dots. 🔬

The result? Surprisingly detailed portraits on a 58mm receipt. 🤯

---

💡 Fun Ideas

• 🎊 Party photo booth — set it up at a gathering, everyone gets a receipt-sized souvenir
• 🎁 Gift tags — snap a photo of a friend, instant personalized gift label
• 🖼️ Receipt art gallery — collect prints, tape them to a wall
• 📝 Visual notes — snap a whiteboard, get a pocket-sized printout

---

🔗 Related

New to the Sunmi V2? Check out sunmi-v2-rescue — our complete guide to debloating, optimizing, and repurposing the device. Covers specs, printer API, performance tweaks, and more.

---

Built with 🤍 on a repurposed Deliveroo POS terminal
_{by Ziad}