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This article introduces how to create natural-looking thumbnail images from 360-degree content (equirectangular format) captured with cameras like Insta360. The Problem: Simple Resizing Causes Distortion 360-degree videos and photos are stored in equirectangular (equidistant cylindrical projection) format. This format unfolds a sphere onto a flat surface, and the closer to the top and bottom edges, the more the image is stretched horizontally. Simply resizing this to create a thumbnail results in a distorted, unnatural image. ...

Overview I had an opportunity to convert audio published on the National Diet Library Historical Sound Archive (hereinafter “Rekion”) to mp4, so here are my notes. Format Provided by Rekion Rekion provides files in m3u8 format. For example, let’s check the following: “Lecture: Union of Morality and Economy (Part 1).” https://rekion.dl.ndl.go.jp/pid/3574643 By checking with developer tools, you can confirm that it is accessible from the following URL. https://rekion.dl.ndl.go.jp/contents/3574643/83389ec6-2b45-4fdd-88d6-89628841039f/317d6ab4-32ec-4085-88e6-cfe36ffd34c3/317d6ab4-32ec-4085-88e6-cfe36ffd34c3_hls.m3u8 The IDs that make up this URL can be found in the response from the following API. ...