Apps similar to Panini include FSPViewer, which is free. Other options are Panorado, SphereView, lux and Pannellum. In total there are eight apps like Panini for Windows, Linux, Mac, self-hosting and the web.
FSPViewer is a free viewer for spherical (equirectangular) panoramic images. It is designed for viewing local (hard-disk, network or CD) high resolution panoramic images at full screen and with very high image quality.
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Panorado is a comfortable image viewer with special support for panoramic and HDR images, with browsing capabilities and some very useful imaging tools.
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Pannellum is a lightweight, free, and open source panorama viewer for the web. Built using HTML5, CSS3, JavaScript, and WebGL, it is plug-in free. It can be deployed easily as a single file, just 15kB gzipped, and then embedded into pages as an <iframe>.
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PPV360HD is an Android and Windows Desktop application designed to view 360-degree panoramic photo with equirectangular or cylindrical projection, at very hi-res resolution.
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Based on PURE technology, ImmerVision's panoramic image viewers combine superior performance capabilities with optimal viewing ease on either a standard office PC monitor or a pocket computer. The "immersive" panoramic experience is no longer limited to desktop...
Canada