Research into Ricoh GR IV firmware, internal interfaces and possible feature extensions. The repository contains analysis notes, offline tools, read-only device probes and reproducible experiments. Feature work currently includes custom shutdown images through the factory-script interface.
| Area | Current work |
|---|---|
| Firmware container | Header and version fields, frame decoding, whole-file checksum |
| System layout | RTOS load mapping, embedded Linux device tree and memory regions |
| USB / MTP | Read-only enumeration and the limits of the tested USB modes |
| Factory and debug interfaces | Persistent Camera Mode state, Version page, key-event paths and TTL startup scripts |
| Model identification | GR IV, HDF and Monochrome product IDs and resource selection |
Start with the research index and developer guide. The research log records experiments and corrections; open questions lists work that still needs evidence. Most detailed reports are currently in Chinese.
Obtain a firmware file yourself. These commands inspect or decode a local container without connecting to a camera:
python3 tools/inspect_firmware.py /path/to/fwdc248b.bin
python3 tools/inspect_firmware.py /path/to/fwdc248b.bin --unpack /tmp/gr4-decoded.binRecord the model, firmware version and sample SHA-256 with each finding. Distinguish file offsets from runtime addresses, and static analysis from camera observations. See the developer guide for the documented RTOS mapping and a contribution checklist.
Firmware, extracted system files, device readbacks and private artwork are not distributed. No installable modified firmware or general-purpose camera SDK is provided. Host-side tests do not emulate the camera hardware.
Shutdown-image guides cover the GR IV family and GR IIIx Urban Edition 1.60, with separate backup, write, readback and restore procedures. Identification and target paths have physical evidence; newer combined templates and wrappers are not fully camera-qualified. Keep a computer backup of each body's original before writing.
docs/
research/ Research index, developer guide and open questions
extensions/ Feature extension guides and experiments
*.md Existing technical reports and experiment log
tools/ Offline analysis, device probes and workflow generators
examples/ TTL experiments and feature templates
tests/ Host-side checks and script control-flow models
Documentation · Tool reference · Examples · Contributing
Use Python 3.10+ and Pillow for the complete test suite. Individual analysis tools may have fewer dependencies; see tools.
python3 -m pip install Pillow
python3 -m unittest discover -s tests -vContributions can include address maps, format documentation, read-only probes, reproducible findings and feature experiments. Include the evidence and limitations, rather than only the final result. See CONTRIBUTING.md.
Newly licensed project material is released under the GR IV Project Noncommercial Source License 1.0. Commercial use requires written permission; this is not an OSI-approved open-source license. Revisions through a55a2c7 and unchanged material from those revisions retain their Apache-2.0 grants. See NOTICE and CONTRIBUTING.md.
Camera modifications carry a risk of data loss or malfunction. Results apply only to the documented test setups. No rights to third-party firmware, artwork or trademarks are granted.
本项目研究理光 GR IV 的固件结构、内部接口和功能扩展可能性，收录分析记录、离线工具、只读探针及可复现实验。目前的功能扩展包括通过工厂脚本接口自定义关机画面。
| 方向 | 已有内容 |
|---|---|
| 固件容器 | 包头、版本字段、帧解码和整文件校验 |
| 系统布局 | RTOS 装载映射、内嵌 Linux 设备树及内存区域 |
| USB / MTP | 只读枚举及已测试 USB 模式的能力边界 |
| 工厂与调试接口 | Camera Mode 持久化、Version 页面、按键事件路径及 TTL 启动脚本 |
| 机型识别 | GR IV、HDF、Monochrome 产品 ID 与资源选择 |
从研究索引和开发者入门开始。研究日志保留实验过程与结论修订，待研究问题列出仍需证据的方向。
自行取得固件文件。以下命令只检查或解码本地容器，不连接相机：
python3 tools/inspect_firmware.py /path/to/fwdc248b.bin
python3 tools/inspect_firmware.py /path/to/fwdc248b.bin --unpack /tmp/gr4-decoded.bin记录每项发现对应的机型、固件版本和样本 SHA-256。区分文件偏移与运行时地址、静态分析与实机观察。开发者指南提供已记录的 RTOS 映射及研究提交要求。
仓库不分发固件、解包系统文件、机身读回数据或私人图稿，目前没有可安装的修改版固件或通用相机 SDK。电脑端测试不等于硬件模拟。
关机图片流程包含 GR IV 系列及 GR IIIx Urban Edition 1.60 的备份、写入、读回和恢复指南。机型识别及目标路径已有实机依据；新组合模板及工具包装尚未整套上机验证。写入前为每台机身保留电脑端原图备份。
docs/
research/ 研究索引、开发者入门、待研究问题
extensions/ 功能扩展指南与实验
*.md 现有技术报告及实验日志
tools/ 离线分析、设备探测及操作包生成工具
examples/ TTL 实验与功能扩展模板
tests/ 电脑端检查及脚本控制流模型
整套测试需要 Python 3.10+ 和 Pillow，各分析工具的依赖见工具说明。
python3 -m pip install Pillow
python3 -m unittest discover -s tests -v欢迎提交地址映射、格式说明、只读探针、可复现发现和功能实验。请附证据、验证范围及未解决问题，要求见贡献指南。
新授权的项目内容采用 GR IV Project Noncommercial Source License 1.0，商业使用须取得书面许可；这不是 OSI 定义下的开源许可证。截至 a55a2c7 的旧版本及其保留的未修改内容仍适用原有 Apache-2.0 授权。详见 NOTICE 和贡献指南。
改机存在数据丢失或设备故障风险，实测结果仅对应文档记录的环境。项目许可证不授予第三方固件、图稿或商标的使用权。