CrowPanel-ESP32 Terminal — Touchscreen Pocket Photo Booth with OV2640 Camera

Portable, custom-built photo booths are traditionally bulky and rely on expensive computer hardware. This tutorial walks you through building an ultra-compact, touchscreen pocket photo booth using the CrowPanel ESP32 3.5 HMI Display module.

By combining an integrated ESP32 microcontroller, a high-resolution camera, and a local Wi-Fi web server, this system creates a self-contained photo-capturing device that lets users preview, capture, apply custom retro filters, and instantly download photos directly to their smartphones and computer.

This project is built for makers, event hosts, and hobbyists who want a self-contained, battery-friendly photo booth without dragging along a laptop or DSLR rig. It is well suited for parties, small gatherings, or maker-fair demo booths, where guests can frame a shot, apply a retro filter, and pull the photo straight onto their phone over the device's own Wi-Fi network.

• ESP32 SoC — A low-cost, low-power system-on-a-chip with integrated Wi-Fi and dual-mode Bluetooth.
• HMI Display — Human-Machine Interface screens designed to visualize data and accept user touch inputs.
• CH340 USB-Serial Bridge — Converts USB signals to serial UART, allowing the computer to communicate with the ESP32.

The ESP32 enters a serial bootloader mode upon reset if specific GPIO pins are pulled low, allowing new firmware to write to flash memory. Data travels asynchronously over TX (transmit) and RX (receive) lines at a matching baud rate.

Gather everything below before you start.

Here is what each component does and why it is part of this project.

The CrowPanel-ESP32 Terminal 3.5" is the main brain and screen of the photo booth. It runs the software, registers screen touches, and displays the user menu. Its built-in Wi-Fi allows users to download photos directly to their phones using the device's IP address.

The OV2640 Camera takes the photos for the booth. It continuously streams a live video feed to the screen so users can frame their shots. When a user taps the screen, the camera instantly captures a clear, high-resolution picture.

The MicroSD Card acts as permanent storage memory. It saves all taken photos in organized folders so they are not lost when the device turns off. It also stores menu graphics and digital photo frames used to decorate pictures.

Wire the camera, storage, display, and feedback components to the board using the tables below.

1. Mount the OV2640 camera module to its parallel-bus and I²C/SCCB header on the back of the CrowPanel board.
2. Insert a formatted MicroSD card into the onboard slot, which shares the SPI bus used for the display.
3. Confirm the buzzer is connected through its NPN transistor stage to BUZZER_PIN (GPIO 45) for shutter-click feedback.
4. Snap the acrylic shell into place once wiring is confirmed, leaving the USB-C port and camera lens accessible.
5. Connect the board to your computer via USB-C for power and firmware flashing.

Follow these steps in order to prepare the Arduino IDE before flashing the firmware.

1. Install the latest stable release of the Arduino IDE.
2. Add the Espressif ESP32 board package through the Boards Manager so the IDE can compile for the Tensilica Xtensa processor used on the CrowPanel.

Use exactly these settings in your IDE. Wrong settings will cause upload failures.

Install the following libraries via the Library Manager:

• LovyanGFX — fast graphics driver for the ILI9488 LCD
• WiFiManager — auto Wi-Fi configuration portal
• esp_camera — official Espressif ESP32 camera driver
• Wire, SPI, and SD — bundled with the ESP32 board core

1. Connect the CrowPanel to your computer via USB-C.
2. Select the correct COM port and the board settings from Step 2.
3. Click Upload.

The firmware is organized into logical blocks. Copy each block below into the correct location in your sketch, and read the Code Breakdown section to understand what each part does. The full code can be seen in number 6.

All pins and dimensions are defined in one place for easy reconfiguration.

#define TOUCH_SDA  2
#define TOUCH_SCL  1
#define TOUCH_ADDR 0x38

#define LCD_MOSI 13, LCD_MISO 14, LCD_SCK 12
#define LCD_CS 3,   LCD_DC 42,   LCD_BL 46

#define SD_CS      10
#define BUZZER_PIN 45

// Camera
#define CAM_XCLK 7, CAM_SIOD 2, CAM_SIOC 1
// ... all data & control pins

#define CAM_W 320, CAM_H 240
#define LCD_W 480, LCD_H 320

Defines the filter enum, a reusable button struct, and all program state flags.

enum FilterMode {
  FILTER_NONE, FILTER_GRAYSCALE,
  FILTER_SEPIA, FILTER_INVERT, FILTER_MIRROR
};

struct Button { int x, y, w, h; const char* label; };

// State variables
bool cameraRunning = false;
bool photoCaptured = false;
bool editingPhoto  = false;
int  editBrightness = 0, editContrast = 0, editHighlights = 0;

Handles camera init, image buffers, filter application, and capture/reprocessing.

bool initCamera(pixformat_t fmt);

// Image buffers
uint16_t* rgbBuf;       // working buffer for processing
uint16_t* originalBuf;  // unmodified original (non-destructive edits)
uint8_t*  capturedJpeg; // final JPEG for display/saving

void applyFilter(uint16_t* buf, int w, int h);
void applyAdjustments(uint16_t* buf, int w, int h,
                      int brightness, int contrast, int highlights);
void swapAllBytes(uint16_t* buf, int count); // fixes byte order

bool capturePhoto();     // takes photo and saves original
bool reprocessCapture(); // re-applies filters/edits from original

The complete Arduino source code is provided as a separate file.

Here is what each part of the code does. Read this after uploading.

initCamera()

capturePhoto() / reprocessCapture()

applyFilter() / applyAdjustments()

startPhotoServer()

connectWiFi() / reconfigureWiFi()

1. setup() — Initializes serial, pins, buffers, LCD, camera, and touch controller; shows the home screen.
2. Home Screen — Waits for START or WIFI SETUP button tap.
3. Live Preview — Streams camera frames to the LCD, applies the selected filter in real time.
4. Capture Review — Displays the captured photo with SAVE WEB, EDIT, SAVE SD, HOME, and REDO options.
5. Edit Mode — Adjusts brightness, contrast, and highlights; calls reprocessCapture() on each change.

After uploading, verify each of the following to confirm the system is working correctly.

Power on the device and confirm the home screen reports Board Status: OK, Touch Status: OK, and Camera Status: READY. If any status fails, recheck the corresponding wiring from Section 04 before continuing.

Tap WIFI SETUP and confirm the device broadcasts a hotspot with on-device instructions for connecting your phone.

Confirm the live camera preview streams smoothly to the display and that all four filter buttons — GRAY, SEPIA, INV, and MIR — change the live image as expected.

The images below show the working system end-to-end, from capture to download. Use these to verify your output matches what is expected.

Captured Photo & Save Options

After tapping SHOT, the captured image is displayed with action buttons.

Browser Web Interface

After tapping Save Web, open a browser on any device connected to the same Wi-Fi and navigate to the device's IP address. The Photo Booth Viewer page lets you load and download the latest captured photo.

Video Demonstration

10 Conclusion

Findings

Possible Improvements and Future Enhancements

11 References

12 Project Authors