SnowAir

Project Overview

When you need to record an on-screen walkthrough, or stitch a long page into a single image, SnowAir offers a tray-resident screenshot toolkit: capture, annotate, long capture, record, OCR, and pinning all happen in one program.

It is written in C++20, runs its UI on a customized Ling framework with Direct2D rendering, and the free edition is a single exe of about 4 MB with a statically linked CRT that runs on double-click. Settings, language files, and plugins live in %AppData%/SnowAir/ by default.

Item	Value
Platform	Windows 10 1803 and above
Stack	C++20 + Ling + Direct2D
Size	Free edition about 4 MB, single file
Trigger	Global hotkey F1, tray icon
License	Apache-2.0

One exe is enough to chain capture, annotation, recording, and recognition together.

Key Features

• Region capture: drag over any area and go straight into annotation, then copy or save the result
• Long capture: scroll and stitch content taller than the screen into one image
• Screen recording: export clips as GIF or MP4, GIF for short demos and MP4 for longer sessions
• OCR: an offline engine recognizes Chinese and English, loaded as a plugin
• Pinning: keep a capture on top of other windows for comparison, reachable with --enter=pin
• Tray and hotkeys: F1 triggers capture by default, and the tray click action can be set to capture, open settings, or nothing under "Feature settings -> Tray click action"
• Presentation canvas: a separate canvas for drawing over the screen during meetings or lesson recording
• Capture history: every capture is archived and can be reviewed or copied again later

Annotation and Output

• Nine annotation tools: rectangle, arrow, pen, text, numbering, mosaic, patina, watermark, and highlight
• Two recording formats: GIF embeds easily in documents, while MP4 suits longer recordings
• Single-file runtime: the CRT is statically linked, so no extra runtime is needed except the OCR plugin
• On-demand plugins: offline OCR and translation components are downloaded under Plugin Integration, and the engine is released after use
• Theme switching: light and dark themes, following the system automatically or set by hand

Editions and Limits

Edition	Form	Feature scope
Free	Single exe around 4 MB, no install	Capture, annotation, long capture, recording, OCR, pinning
Pro	Separate build on Qt6	Adds AI models, screen mirroring, super actions, and quick translation on top of the free edition

Quick Start

First run

1. Run SnowAir-Lite.exe; it only sits in the tray and does not start a capture
2. Press F1 or click the tray icon to begin
3. Drag over the area, pick annotation tools in the toolbar, then copy or save
4. Right-click the tray icon to open the settings center for hotkeys, tray behavior, and plugins
5. To keep settings next to the program, place an empty config.json beside the exe

Command line

1. SnowAir.exe --enter=long goes straight into long capture
2. SnowAir.exe --enter=video starts recording immediately
3. SnowAir.exe --auto-quit=true exits once the capture is done
4. Running the exe again opens the settings center

System Requirements

Item	Requirement
OS	Windows 10 1803 and above, Windows 11
Runtime form	Single exe, no installation
Runtimes	None beyond the statically linked CRT
Data folder	%AppData%/SnowAir/ for settings, languages, plugins, and history
Source environment	Visual Studio 2026 (v145 toolset) and the Windows 10 SDK

Notes

• No source build: the core is Apache-2.0 licensed, but it depends on a customized Ling whose deps/Ling is not published, so use the released exe
• OCR needs a component: download the engine and language packs under Plugin Integration, or drop ImageReader.exe into %AppData%/SnowAir/plugin or the exe folder
• Pro-only features: screen mirroring, super actions, AI models, and quick translation ship only with the Pro edition
• No capture by default: launching without arguments only sits in the tray, and F1 is the capture entry
• Portable mode is manual: config.json must be an empty file beside the exe, and deleting it returns to the %AppData% settings