This is a file from the Wikimedia Commons. The description on its description page there is shown below.
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Summary
Based on Image:Japanese-War-Ensign.svg, but refactored by User:Denelson83 to fix a problem that results in the image getting altered when scaled down.
This image shows a flag, a coat of arms, a seal or some other official insignia. The use of such symbols is restricted in many countries. These restrictions are independent of the copyright status of the depiction shown here.
Licensing
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
File links
The following pages on the English Wikipedia link to this file (pages on other projects are not listed):
This is a list of all flags available here, mostly national and regional flags. ... The Japan Self-Defense Forces (Japanese: èªè¡é, Jieitai) or JSDF, are the military forces in Japan that were established after the end of World War II. The force has been engaged in no real combat but has been engaged in some international peacekeeping operations. ...