HDRViewer

*Vibe coding Project

HDR image viewer — native C++ / WinAPI desktop application, with native Windows 11 HDR display pipeline support (scRGB / ST.2084 / HLG), inspired by Jpegview.

Features

• Native HDR: DXGI R16G16B16A16_FLOAT swap chain with automatic display HDR detection and ST.2084 color space configuration
• Color pipeline: sRGB / PQ (ST.2084) / HLG / Scene Linear → scRGB conversion, preserving full dynamic range
  *Triggers system Auto HDR on SDR displays via registry configuration

Keyboard & Mouse

Open images via: drag & drop onto the window, Ctrl+O file dialog, command-line argument, or dropping a file onto the EXE icon

Input	Action
Scroll wheel	Zoom
Left drag	Pan image
Double-click / F11	Toggle fullscreen
Ctrl+O	Open file
0	Reset to 1:1
← ↑ / → ↓	Previous / next image
Esc	Exit
Right-click	Context menu

Building

Prerequisites

• Visual Studio 2022 (MSVC, CMake 3.28+)
• Windows 10/11 SDK
• vcpkg

# Install third-party libraries (static triplet recommended)
vcpkg install --triplet x64-windows-static libjxl openexr

# stb_image.h is bundled in thirdparty/ — no extra install needed

Compile

cmake -B build -G "Visual Studio 17 2022" -A x64
cmake --build build --config Release

Output: build\Release\HDRViewer.exe (≤ 3 MB, statically linked)

Run

.\build\Release\HDRViewer.exe
.\build\Release\HDRViewer.exe "C:\path\to\image.jxr"

If you want to make it the default software for HDR images, please register it through register.cmd, and unregister through unregister.cmd

Format Support

Format	Decoder	HDR
.jxl	libjxl	✅ PQ / HLG
.exr	OpenEXR	✅ Scene Linear
.jxr / .wdp / .hdp	WIC (HD Photo codec)	✅ FP16
.png / .jpg / .bmp / .tga / .gif	stb_image	SDR → HDR up

Architecture

src/
├── main.cpp              # WinMain, command-line parsing, message loop
├── MainWindow.h/cpp      # Window class: message dispatch, zoom/pan/fullscreen logic
├── ImageDecoder.h/cpp    # Unified decode interface, per-format adapters
├── ColorPipeline.h/cpp   # sRGB/PQ/HLG → scRGB color conversion
├── HDRDisplay.h/cpp      # DXGI HDR detection, FP16 swap chain
├── Renderer.h/cpp        # Direct2D/3D rendering, DWrite text overlay
├── SlideShow.h/cpp       # Slideshow (directory enumeration, sorting)
├── RegistrySetup.h/cpp   # Registry settings for Auto HDR / GPU preference
├── Resource.rc           # Icon, manifest
└── app.manifest          # DPI / Win10+ compatibility

License

GPL-2.0

References

• sylikc/jpegview — interaction style blueprint
• microsoft/DirectX-Graphics-Samples — D3D12HDR reference