<div dir="ltr"><div>An image is georeferenced if there is some form of associating pixel positions (row, column) to geolocation, in geographic or cartographic coordinates.<br>Proj, or any other program that uses proj, needs that to apply map projection formulas<br></div>In your case you must simulate that your image is georeferenced, giving it an extent of 360 degrees in longitude (row) and some proportional extent in latitude (column).<br><div>Regards<br><br></div><div>Jose<br></div><div><br><div><div class="gmail_extra"><br><div class="gmail_quote">2016-05-25 0:34 GMT+01:00 Wang Leslie <span dir="ltr"><<a href="mailto:wqyuwss@hotmail.com" target="_blank">wqyuwss@hotmail.com</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p>Hi Jose,</p>
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<p>Thanks for the quick reply.</p>
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<p>What do you mean "be geo-referenced"? What I'm thinking is to use these tools to convert a 360 panorama picture, such as <a href="https://upload.wikimedia.org/wikipedia/commons/3/35/Space_Needle_360_Panorama.jpg" title="https://upload.wikimedia.org/wikipedia/commons/3/35/Space_Needle_360_Panorama.jpg
Cmd+Click or tap to follow the link" target="_blank">https://upload.wikimedia.org/wikipedia/commons/3/35/Space_Needle_360_Panorama.jpg</a>,
which is an equidistant cylindrical projection, to other type of projection, which keeps same quality but with smaller size. Thus I can save some storage spaces. In this case, these 360 picture doesn't have any geo-referenced data. Can I still use these tools? </p>
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