XnView
XnView MP/Classic is a free Image Viewer to easily open and edit your photo file. The Image Viewer supports all major image formats (JPEG, TIFF, PNG, GIF, WEBP, PSD, JPEG2000, OpenEXR, camera RAW, HEIC, PDF, DNG, CR2). As Image Viewer you have features like color adjusting, image resizer, cropping, screen capture, metadata editing (IPTC, XMP) and much more. With its easy-to-use explorer-like interface, XnView MP allow you to quickly view your images and photos, but also to make image management. You have features like batch rename, batch converter, duplicate image finder, image compare, but you can also create contact sheets, slideshow.
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Image Viewer Ultimate
Image Viewer Ultimate is a great application to view/run slideshows of your images/photos and it is also having batch resize and batch watermark features. Fit to actual size, zoom in, zoom out, full-screen mode, and play images as a slide show on Windows. Set slideshow time, setting available through application preferences. Supports retina display. Can export images as JPEG, PNG, TIFF, JIF, BMP. Batch conversion to the desired format as JPEG, PNG, TIFF, JIF, or BMP. Batch watermark to desired images. Save images in the desired size.
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Pixea
Pixea is an image viewer for macOS with a nice minimal modern user interface. Pixea works great with JPEG, HEIC, PSD, RAW, WEBP, PNG, GIF, and many other formats. Provides basic image processing, including flip and rotate, showing a color histogram, EXIF, and other information. Supports keyboard shortcuts and trackpad gestures. Shows images inside archives, without extracting them. Supports JPEG, HEIC, GIF, PNG, TIFF, Photoshop (PSD), BMP, fax images, macOS and Windows icons, radiance images, and Google's WebP. RAW formats Leica DNG and RAW, Sony ARW, Olympus ORF, Minolta MRW, Nikon NEF, Fuji RAF, Canon CR2 and CRW, Hasselblad 3FR. Sketch files (preview only) and ZIP archives. Export JPEG, JPEG-2000, PNG, TIFF, and BMP. Pixea supports animated GIF, PNG, and WebP images.
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LightCraft
LightCraft is an open-source photo library and RAW editor for photographers who want to organize and develop images locally. It imports photos into albums and folders and supports ratings, flags, metadata search, sorting and duplicate detection. Non-destructive tools cover exposure, tone and color adjustments, crop and geometry, presets, black-and-white conversion, and local masks. It reads multiple camera RAW and common image formats and exports JPEG, PNG, TIFF, WebP and DNG. Users can compare edits, synchronize settings across selected photos, and create contact sheets. LightCraft runs on macOS, Windows and Linux; a WebAssembly build can be self-hosted. A command-line interface, JSON control channel and MCP server support automation. The library is stored locally, without an account or cloud service.
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