# NJFE: a Soulear camera protocol bridge for desktop inspection

> Reuses otoscope's reverse-engineered i4season/Soulear protocol in an ESP32-C3 bridge and Python desktop viewer. The author credits Claude Code for implementation and reports streaming one Hopefox Find T to a Windows PC, with recording, orientation and LED controls.

- Type: Case study
- Targets: Protocol
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-10-17
- Added to the catalog: 2026-10-17
- Original resource: <https://github.com/WildweaselMS/NJFE>
- Primary source: <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/README.md>
- Catalog page: <https://awesomerea.org/resources/njfe-ear-camera-bridge-case/>
- Record JSON: <https://awesomerea.org/resources/njfe-ear-camera-bridge-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/njfe-ear-camera-bridge-case/index.md)

## Requirements & limits

- **Prerequisites:** Builds with PlatformIO espressif32 6.11.0, Arduino core 2.0.17 and U8g2 ^2.35.30; the desktop tools need Python with Tkinter, pyserial >=3.5, opencv-python >=4.8, NumPy >=1.24 and Pillow >=12.3.0. Only Windows testing is reported.
- **Scope:** Input is the camera’s Wi-Fi i4season/Soulear UDP traffic. An ESP32-C3 SuperMini with a 0.42-inch, 72×40 SSD1306 OLED reassembles JPEG frames and sends them with accelerometer data over custom USB CDC serial to the viewer. It is not a UVC webcam, the camera’s USB port is charge-only, and no vendor firmware or full app source is recovered.
- **Attribution:** Packet format, commands, frame assembly and rotation logic are credited to rbeilvert/otoscope, which reverse engineered Soulear’s libWifiCamera.so; NJFE does not pin the borrowed revision.
- **Testing evidence:** Results come from a single HKV41B-firmware Hopefox Find T (480×480 JPEG at about 17 fps). The --test N mode needs the hardware and there is no offline conformance suite.
- **Limits:** The camera network is open: the bridge accepts unauthenticated UDP that can inject images or replies, serial access is trusted and recordings are unencrypted. It is an inspection tool, not a medical device.
- **License:** GPL-3.0-or-later, with protocol code and roll calculation derived from GPL otoscope; third-party libraries keep their licenses, and no rights to vendor software or images are granted.

## Primary sources

1. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/README.md>
2. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/NOTICE>
3. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/REUSE.toml>
4. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/LICENSE>
5. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/SECURITY.md>
6. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/wifi_scanner/platformio.ini>
7. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/wifi_scanner/tools/requirements.txt>
8. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/wifi_scanner/src_i4season/main.cpp>
9. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/wifi_scanner/tools/viewer.py>
10. <https://github.com/WildweaselMS/NJFE/blob/992866c6609f8c813f459ff79840cf04d5883f8e/wifi_scanner/tools/gui.py>
11. <https://github.com/rbeilvert/otoscope/blob/d14ac8e368854146ded4f3347614a24539e6696a/README.md>
12. <https://github.com/rbeilvert/otoscope/blob/d14ac8e368854146ded4f3347614a24539e6696a/app/src/main/kotlin/dev/rubec/otoscope/stream/i4season/I4seasonProtocol.kt>
13. <https://github.com/rbeilvert/otoscope/blob/d14ac8e368854146ded4f3347614a24539e6696a/app/src/main/kotlin/dev/rubec/otoscope/stream/i4season/FrameAssembler.kt>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.