# StViewer (STellar image Viewer)

## Overview  
StViewer (hereafter referred to as "this app") is a multi-functional image viewer application.  
In addition to supporting major image formats, it can display images compressed within .zip archives.  
It supports animated .gif and .webp, .svg vector images, JPEG XL, iPhone's .heic, and .avif.  

Furthermore, it includes a wide variety of features conceptualized by the author (SATOX), such as animation effects leveraging GPU capabilities, printing (PDF output), text extraction (OCR), color picking, and a "Ghost Window" mode (transparent window).  

## System Requirements  
- Windows 10 or later (Tested on Windows 11)  
- 64-bit OS (x64) only  
- .NET 8.0 Runtime (https://dotnet.microsoft.com/en-us/download/dotnet/8.0)  


## Feature Summary  
1. **Japanese** and **English** support
2. **Supported File Formats**
    - General / Archive: .zip / .png / .jpg (.jpeg) / .bmp / .ico / .tif (.tiff) / .tga
    - Animation: .webp / .gif
    - Next-Gen / High Efficiency: .webp / .avif / .heic (.heif) / .jxl / .jp2 (.jpf)
    - Specialized / Vector: .psd / .svg / .exr / .dng / .dds
    - Folder support: Displays images within a specified folder.
3. **Mouse Operations**
    - Drop image files or zip files to view them
    - **Mouse Wheel** : Next / Previous image (Shift key for ±10)
    - **Ctrl + Mouse Wheel** : Image zoom
    - **Left Double-Click** : Next image (Ctrl for Previous, Shift for ±10)
    - **Left Drag** : Seek images within folder/archive (Shift for ±10)
    - **Right Drag** : Display Magnifier
    - **Right + Left Button Vertical Drag** : Image zoom
    - **Middle Button Drag** : Image panning
    - **Forward Button** : Next folder or archive
    - **Back Button** : Previous folder or archive
    - HUD Buttons
        - **HUD Right Button** : Next image
        - **HUD Left Button** : Previous image
        - **HUD Up Button** : To the beginning of the folder or archive
        - **HUD Down Button** : To the end of the folder or archive
        - **HUD Folder Button** : Toggle built-in File Viewer
        - **HUD Maximize Button** : Toggle Fullscreen mode
        - **HUD Close Button** : Exit application
4. **Toolbar Button Operations**
    - Select images via file dialog
    - Toggle built-in File Viewer
    - To the beginning of the folder or archive
    - Previous archive
    - Previous folder
    - Previous image
    - Next image
    - Next folder
    - Next archive
    - To the end of the folder or archive
    - Filter toggle (Dropdown)
    - Show About dialog (Version, documentation link)
5. **Keyboard Operations** - **0–9 (including Numpad)** : Seek to 0%–90% position within archives, folders, or animations
    - **Numpad +** : Animation skip frames +1
    - **Numpad -** : Animation skip frames -1
    - **Numpad .** : Reset animation skip frames
    - Other shortcuts are displayed in the right-click menu
6. **Built-in File Viewer (🧪 Experimental)**
    - Select folders and files using the in-app filer
7. **Magnifier**
    - Right-drag to show a magnified view of the area under the cursor
8. **Loop Settings**
    - Loop within folders (continuous navigation within a group)
    - Loop within archives (continuous navigation within a group)
9. **Auto-Rotation**
    - Automatically rotates images to maximize display area
10. **Effects (🧪 Experimental)** (* denotes animation effect)
    - Grayscale
    - Sepia
    - Blur
    - High Contrast
    - Edge Detect
    - Surface Blur
    - Pixelate
    - Retro Graphics
    - Skin Smooth (Brightening)
    - Halftone
    - Thermal
    - *Glitch (Chromatic Aberration)
    - *Retro CRT
    - *Kaleidoscope
    - *Entropy Dissolve
    - *Manga FocusLines
    - *Water Ripple
    - *Night Vision
    - *Lovely Heart
    - *God Ray
    - *Miniature
    - *Color Splash (Selective Color)
    - *Rain
    - *Snow
    - *Cherry Blossom
11. **Fullscreen Mode**
    - Displays images in full screen, hiding the title bar and taskbar
12. **Always on Top**
    - Keeps the window on top of other applications
13. **Zoom & Panning**
    - Fit-to-screen (Default)
    - Manual scale ratio
14. **Dot-by-Dot (Nearest Neighbor)**
    - Automatically uses Nearest Neighbor scaling when blur is significant due to enlargement
15. **HUD Toggle**
    - Suppresses certain UI messages
16. **Real-time Histogram (🧪 Experimental)**
    - Displays the image histogram
17. **Exif Data (🧪 Experimental)**
    - Displays JPEG Exif information
18. **Paste from Clipboard**
    - Paste and view bitmap images from the clipboard
    - Saved to a temporary folder and deleted upon application exit
19. **Copy to Clipboard**
    - Copy images (Bitmap) to the clipboard for use in other apps
20. **Color Picker**
    - Copies the color under the cursor in WEB format
    - Format: #RRGGBB (if alpha disabled) or #AARRGGBB (if alpha enabled)
21. **Transparency Settings**
    - Toggle checkerboard pattern for transparent images
    - White, Black, Gray also available
22. **Blur Backdrop**
    - Displays a blurred version of the image in the background
23. **Background Color**
    - Customize the background color
24. **Ghost Window**
    - Enter a semi-transparent mode where mouse clicks pass through the window
    - Press ESC to exit
25. **System Context Menu**
    - Access the standard Windows context menu for the current file
26. **Show in Explorer**
    - Opens the folder and highlights the current file in File Explorer
27. **OCR**
    - Extract text from the current image using OCR
28. **Printing / PDF Output (🧪 Experimental)**
    - Print images or save them as PDF
    - Auto-rotates to fit paper size optimally
29. **File Sharing**
    - Invokes the native Windows Share functionality
30. **File Association**
    - Associate supported file types via the initial startup dialog
    - Hold Shift while exiting to remove associations
31. **Taskbar Recent Files**
    - Files opened directly are registered in the taskbar's "Recent" list
32. **Auto-Hide Cursor**
    - Hides the cursor when it remains stationary over the viewer

## File List
- StViewer.exe      : The application executable
- StViewer.settings : The settings file (created upon exiting)
- Readme(JP).md     : This document
- LICENSE.txt       : Third-party license text file

## Resetting Settings  
- To reset your settings, delete `StViewer.settings` before launching the application.

## File Association  
- Upon the first launch, a dialog will ask if you want to associate file types with this app.
    - To show this dialog again, delete `StViewer.settings` before launching.
    - Once associated, "StViewer" will appear in the right-click menu of supported files.

## Removing File Association  
- You can remove associations by **holding the Shift key while closing the application**.
- Please perform this operation before uninstalling the app.

## Support  
- For bug reports or feature requests, please contact the author.    
    - Author: SATOX (https://x.com/satoxpochi)  
    - Website: https://satox.skr.jp/StViewer

## Version History  
### Ver.1.1.9534 (2026-02-07)  
- New Features
    1. Added 9 new effects
        - Water Ripple, Night Vision, Lovely Heart, God Ray, Miniature, Selective Color, Rain, Snow, Cherry Blossom
    1. Added sort order settings for files and archives
        - Internal "Next/Previous" order can be toggled between "File Name" and "Date"
- Changes
    1. Updated folder navigation to follow archive loop settings (previously looped by default)
- Bug Fixes  
    1. Fixed an issue where an exception dialog appeared when closing multiple instances of the app simultaneously
        - App settings from the first instance launched will be the ones saved.  

### Ver.1.0.9509 (2026-01-13)  
- Initial release  

## Disclaimer  
Copyright (c) 2025-2026 SATOX All rights reserved.

StViewer is provided "as is," without warranty of any kind, express or implied, including but not limited to the warranties of completeness or fitness for a particular purpose.

1. **Liability**: The author shall not be held liable for any direct or indirect damages (including data loss, hardware failure, or financial loss) arising from the use or inability to use this application.  
2. **Prohibitions**: Reverse engineering, modification, and unauthorized redistribution or reposting to other sites/media are strictly prohibited.  
3. **Copyright**: All copyrights and intellectual property rights related to this application belong to the author.  

## License 
This application uses third-party libraries listed in "LICENSE.txt".

Special thanks to the developers of these excellent Open Source projects.