RED R3D / N-RAW support

EXR Converter can decode RED R3D (.r3d) and Nikon N-RAW (.nev) clips when built against the official RED R3D Software Developer’s Kit. Without the SDK bridge, those extensions are recognized in the UI but conversion fails with a clear “SDK missing” message.

Related: CLI · GUI · AGENTS.md

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#What you get

Scale maps to the SDK resolution ladder (full / half / quarter / …) for faster proxies; odd scale factors may apply a small software resize after decode.

The SDK is cross-platform, but GPU APIs are not one path: Metal on macOS (full GPU decompress), CUDA then OpenCL on Windows/Linux via managed R3DDecoder (CPU decompress + GPU IPP2). CUDA needs an NVIDIA driver and the CUDA runtime (cudart) on the library path; OpenCL needs a GPU ICD. No extra compile-time CUDA/OpenCL SDK is required to build the bridge.

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#License (read this)

The R3D SDK is proprietary (RED.COM / Nikon). Terms live in the SDK License Agreement shipped with the SDK package. Always verify the copy you downloaded.

Summary of constraints that affect this project (not a substitute for the legal text):

• Royalty-free use to build applications that add significant functionality.
• You may redistribute only the Redistributable dynamic libraries (+ LUTs in original form) in a private (non-shared) directory used only by your app.
• You must not redistribute: headers, static libraries, sample source, or documentation.
• End-user distribution must include required EULA language protecting RED (no reverse engineering, ownership, disclaimers, liability limits, etc.).
• Pure open-source licenses can conflict with those mandatory end-user restrictions. Practical options: optional/offline install of redistributables, clear docs, and a product EULA when shipping binaries that include RED libs.

Do not commit the R3D SDK tree into the public git repository. The R3D bridge source is not in this public repo: it is proprietary and lives in the private derek-rein/r3d-sdk-private repo (bridge/), fetched at build time by scripts/build_r3d_bridge.py. This repo only contains the build wrapper and Python ctypes glue (src/core/r3d.py).

Contact RED for edge cases: [email protected].

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#Where the full SDK lives (maintainers)

Public GitHub Release artifacts for EXR Converter may include only:

• libr3d_bridge.{dylib,so,dll}
• RED Redistributable/* dynamic libraries

…under a private app folder (…/r3d/), never headers or static libs.

#Refresh the private CI feed

# After unpacking a new official SDK under ~/code/r3d-sdk-private/R3DSDKv9_*
cd ~/code/r3d-sdk-private
./scripts/package_release.sh
# retags/uploads R3DSDKv9_2_1-full.tar.gz to release sdk-9.2.1

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#Developer setup (local)

# Full SDK already at the recommended path:
#   ~/code/r3d-sdk-private/R3DSDKv9_2_1

cd ~/code/exr-converter
make r3d-bridge
# → build/r3d/libr3d_bridge.* + build/r3d/redistributable/

# Or pull the same tarball CI uses (needs gh auth or R3D_SDK_READ_TOKEN):
make r3d-sdk-fetch   # → .r3d-sdk/R3DSDKv9_2_1 (gitignored)
make r3d-bridge

Override discovery:

Convert:

uv run python main.py video2exr -i /path/clip.R3D -o /tmp/exr_out \
  --src "Log3G10 REDWideGamutRGB" --dst ACEScg

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#CI / GitHub Release builds

The Release workflow (Nuitka multi-OS):

1. If secret R3D_SDK_READ_TOKEN is set → download sdk-9.2.1 / R3DSDKv9_2_1-full.tar.gz from the private repo.
2. Build libr3d_bridge (macOS / Linux / Windows + MSVC).
3. After Nuitka, copy bridge + Redistributable only into …/r3d/ next to the executable.
4. Refuse the build if headers / .a / .lib appear under that folder.

If the secret is missing, Release still publishes the app without R3D support.

# Set or rotate the secret (fine-grained PAT with read on r3d-sdk-private is ideal)
gh secret set R3D_SDK_READ_TOKEN --repo derek-rein/exr-converter

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#Packaging layout (shipped)

macOS:  EXR Converter.app/Contents/MacOS/r3d/
Linux:  <dist>/r3d/
Windows:<dist>/r3d/
          libr3d_bridge.*
          REDR3D.*  REDDecoder.*  …   # original Redistributable names only

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#Troubleshooting

Sample clips (from RED / Nikon, not this repo):

• https://www.red.com/sample-r3d-files
• Nikon N-RAW / R3D NE sample downloads (see SDK Readme.txt)

#Bridge source location

scripts/build_r3d_bridge.py finds the confidential bridge source via R3D_BRIDGE_SRC, ~/code/r3d-sdk-private/bridge, or by downloading the derek-rein/r3d-sdk-private tarball at R3D_BRIDGE_REF (default bridge-v1) using R3D_SDK_READ_TOKEN / gh auth. Without access, builds skip the bridge and the app reports the format as unavailable.