Use One Photo Viewer
Basic usage
Full list of keyboard shortcuts
Additional config file settings
Set One Photo Viewer as ​default photo viewer
1. Open Windows start menu and click the settings icon (the gear).
2. Click "Apps" then "Default apps" and click on "Photo viewer" selection.
3. If you already have One Photo Viewer install then select it and your done. Else choose "Look for an app in the Store" and find One Photo Viewer there.
Sort images as in Windows File Explorer
By default images is sorted by name in OPV. This can be changed so images is sorted as in the Explorer folder you opened it from; Right-click menu -> "More settings" -> "Sort as in Explorer". This is not default because for some users it makes OPV start very slow or become unresponsive for a while. For most users it doesn't affect performance.
RAW format support
Extend format support by installing Raw Image Extension from Microsoft store. Most RAW formats can then be viewed in One Photo Viewer. But no guarantee it will work.
WebP format support
One Photo Viewer have support for WebP image format if codecs is installed. But no guarantee it will work. Download and install WebpCodecSetup (SHA256: C7D57B93F93269E78AE0A0BE660293822282EDC5EEFA7B304F17D621AF334BDF).
HEIC / HEIF format support
Install HEVC Video Extensions (no longer free on MS Store, cost $0.99) and HEIF Image Extensions to get HEIC image support in One Photo Viewer. But no guarantee it will work. If the extention do not work the first time try reinstall or uppdate HEIF Image Extensions.
AVIF format support
Install AVI Video Extension from MS Store and also HEIF Image Extensions from MS store. AVIF still images should then show in One Photo Viewer. But no guarantee it will work.
Macro script to batch process images
See how to use keyboard macros to batch process images here
Slideshow autostart and other .bat script functions
One Photo Viewer can be started from command prompt or batch script (.bat). For example you can place a .bat script in a folder, double click it and a slideshow will start automaticly. See how it's done here
Administrator options
One Photo Viewer can be used in a server environment (Citrix, Dynamics AX, Microsoft configuration manager) with the legacy installer. It can be deployed silently by the argument /S as >.\OPV_Setup_v1-18-1-0.exe /S
Sometimes admin want to set other default config settings for users or block functions to protect data on a server for example. This is how to do it. Install One Photo Viewer with the legacy/Windows 7 installer. Then edit this file, OPV_admin.config, and place it in the same location as the executable One Photo Viewer.exe (usually located at %programfiles%\One Photo Viewer\). All settings/rows in OnePhotoViewer.config (F2) can be set to a fixed value by adding it to this admin config file.
Reset settings file
If the software does not behave as it should, for some reason. You can reset the settings to default values by pressing Shift+Ctrl during start of the software. Best to start the software from Windows start menu. If holding shift while double click on an image you may accidentally open a whole bunch of images.
Set background to arbitrary color
Pressing Ctrl+Alt+Shift while click and drag left mouse over the image will change the background color to the color beneath the mouse. Or you can edit the config-file by pressing F2 and edit key="background" value="DarkRed" for example. See X11_color_names, but remove spaces in color name. If you want same background at every start but still be able to change it temporary you can add the lock="true" attribute to the config file value (see example at top of config-file).
Use eraser tool
Pressing Ctrl+Shift while click and drag left mouse over the image will set a square beneath to background color. First select background color black, white, transparent or arbitrary color see above. If you using transparent background save the image in PNG format. While holding Ctrl+Shift you can change the eraser tool size by the mouse wheel.
Erase a color
Pressing Ctrl+Alt while click and drag left mouse over the image will set the color beneath to background color. First select background color black, white, transparent or arbitrary color see above. If you using transparent background save the image in PNG format. This feature is not so useful for photos, since only the specific color beneath the mouse will be affected. But can be useful for editing screenshots and other computer generated images. While holding Ctrl+Alt you can increase the size of area measured by the mouse wheel, but it becomes very CPU intensive in increased.
Make stylized text
There is an extra feature built-in to OPV that generates stylized text, from any text file, based on a set of character images you easily edit yourself. For more info on this goto onephotoviewer.com/stylized-text