QuickImageViewer (QIV)

A fast, GPU-accelerated image viewer for Windows.
Built on Direct2D, WIC, and native Win32 APIs. Single EXE, no installer, no telemetry, ~7 MB.

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Preview

Main Interface	Shortcuts Reference

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Download

→ Latest Release

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Format Support

Format	Extensions	Decoder	Notes
JPEG	.jpg .jpeg	WIC	Full EXIF / GPS metadata
PNG	.png	WIC	16-bit, alpha
BMP	.bmp	WIC
TIFF	.tif .tiff	WIC	Multi-page (first frame)
GIF	.gif	WIC	Static (first frame)
WebP	.webp	WIC	Windows 10+ native codec
HEIF / HEIC	.heif .heic	WIC	Requires MS HEIF Extensions
AVIF	.avif	WIC	Windows 11 native codec
JPEG XL	.jxl	WIC	Windows 11 24H2+ native codec
JPEG 2000	.jp2 .j2k	OpenJPEG	Static lib
SVG	.svg	resvg	Rust static lib, async IO thread
OpenEXR	.exr	tinyexr	Reinhard tone-map + γ2.2
Radiance HDR	.hdr	Inline	RGBE adaptive RLE, Reinhard tone-map
PNM	.ppm .pgm .pbm	Inline	P1–P6, up to 16-bit maxval
QOI	.qoi	Inline	Lossless fast format
ICO	.ico .cur	WIC

WIC = Windows Imaging Component (OS native, zero dependency)
Inline = implemented directly with no third-party library

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Features

Performance

• GPU bitmap cache — decoded images live in VRAM, preloaded in both directions
• Background decode — worker thread pool; UI thread never blocks on IO
• Instant startup — process stays resident in RAM after first launch (hide to tray with Esc, recall instantly)
• Software fallback — GDI renderer for edge cases where Direct2D is unavailable

Navigation

• Next / prev with → ← or scroll wheel
• Sort by name, date modified, file size, extension, or physical disk order
• Toggle between first and last image in folder (Backspace)
• Toggle between current and previous folder (Q)
• Full folder history with favorites, sorted by visit frequency
• Drag & drop, CLI argument, registered file handler
• Multi-instance aware — multiple windows supported

UI Panels

Panel	Shortcut	Description
EXIF / Info	M	Full metadata: camera, capture settings, GPS with offline geocoding
Directory	F5 / F6	All images in current folder; syncs selection with viewer
Cache	F3 / F4	Live GPU cache occupancy, thumbnails of preloaded images
History	Tab	Recent folders with favorites; Shift+Enter opens in DirWnd
Help	F1	Full keyboard shortcut reference

Offline Reverse Geocoding

GPS coordinates in EXIF are resolved to full location data with zero network calls. All data is compressed (zlib) and embedded directly in the EXE.

Data	Source	Entries	Shows
Cities	GeoNames cities1000	170,387	City name, timezone
Admin1	admin1CodesASCII	3,865	State / Province
Admin2	admin2Codes	47,549	District / County
Country	countryInfo	252	Country, Capital, Continent, Currency, Phone prefix

Example output in the EXIF panel for a photo taken in Paris:

City        Paris
District    Paris
State       Ile-de-France
Country     France
Continent   Europe
Capital     Paris
Currency    EUR (Euro)
Phone       +33
Timezone    Europe/Paris

Color Effects

All effects are non-destructive and GPU-accelerated via the Direct2D effect graph. Ctrl+S saves the result to disk.

Effect	Key
Grayscale	Del
Invert	Ins
Sepia	Home
Solarize	End
Outline	PgUp
Threshold	PgDn
Brightness ±	\ / '
Contrast ±	/ / .
Saturation ±	[ / ]
Gamma ±	= / -
Toggle all effects	`
Reset all	Num0

Overlay System

9 independently configurable data slots rendered on the image canvas. Each slot shows contextual info (filename, index, zoom, dimensions, file size, effects state) and can be toggled, repositioned, or set to compact mode individually.

[Ctrl+1] Top Left    [Ctrl+2] Top Center    [Ctrl+3] Top Right
[Ctrl+4] Mid Left    [Ctrl+5] Center        [Ctrl+6] Mid Right
[Ctrl+7] Bot Left    [Ctrl+8] Bot Center    [Ctrl+9] Bot Right

Master toggle: N or I — Layout cycle: O — Background: P — Compact per slot: Ctrl+Alt+1–9

Transform

• Rotate view: R
• Flip horizontal: H
• Flip vertical: V
• Copy to clipboard: Ctrl+C
• All transforms are non-destructive (view only)

Window & Chrome

• Fullscreen: F11 / F / Enter
• Always on top: Ctrl+T
• Move window: Shift+WASD
• Snap to screen zones: Alt+WASD and Alt+Q/E/Z/C
• Opacity: Shift+Wheel
• Resize: MMB drag
• Round / square corners toggle: Num*
• Backdrop type cycle: Num/
• Runtime theme factor: Ctrl+Alt+Num+/-

Mouse Shortcuts

Input	Action
Wheel	Previous / next image
Ctrl+Wheel	Zoom in / out
Shift+Wheel	Adjust opacity
LMB hold	Quick zoom 3× centered on cursor
LMB drag (zoomed)	Pan; reverts on release
RMB hold / drag	Move window
RMB + LMB	Reveal current file in Explorer
MMB click	Reset zoom / pan / opacity, center window
MMB drag	Live-resize window from top-left
Double-click	Toggle fullscreen

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Architecture

• Renderer — Direct2D + D3D11 with GPU bitmap cache. GDI software fallback. Full ID2D1Effect graph for color operations.
• Decoding — WIC pipeline for OS-native formats. Custom decoders (SimpleFormats.cpp) for EXR, HDR, PNM, QOI. SVG via resvg on a background IO thread.
• Threading — Worker thread pool for background decode and preload. Atomic wantedIndex prevents stale frames. WM_QIV_REPAINT / WM_QIV_SVG_READY messages synchronize back to the UI thread.
• Caching — GPU bitmap cache with configurable size. Preloads adjacent images in both directions. Live cache inspector panel.
• DPI — Per-monitor DPI aware V2. All layout scales via MulDiv(GetDpiForWindow(...)).
• Persistence — Registry-backed settings. Folder history manager. Favorites system.

Third-Party Libraries

Library	Purpose
resvg	SVG rasterizer (Rust static lib)
OpenJPEG	JPEG 2000 decoder
tinyexr	OpenEXR decoder
miniz	zlib compression for embedded GeoNames data

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Build

Requires CMake and MSVC (Visual Studio 2022 or CLion).

git clone https://github.com/icyhoty2k/QuickImageViewer.git
cd QuickImageViewer
mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
cmake --build . --config Release

For offline geocoding, generate the GeoNames binary resources before building:

# Download cities1000.txt, admin1CodesASCII.txt, admin2Codes.txt, countryInfo.txt
# from geonames.org and place them in resources/geoData/
python tools/preprocess_cities.py

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License

Licensed under the GNU Affero General Public License v3.0 (AGPLv3).