How to convert large images into zoomable tiles (no map)
This article will show you how to turn a (large-scale) raster image into zoomable tiles with no geographical location. This process is used in GLAM (gallery, library, archive, museum) institutions for processing and publishing large-scale imagery on the web. This is also perfect for publishing large-scale photography in biology and science institutes. The final publishing on the web is done via a standard JavaScript library - with all advantages of a zoomable viewer.
Make your image zoomable
At first, you can go through the whole process in a short video:
Step-by-step workflow
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Choose your image.
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Open MapTiler Engine and load your image.
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Skip the selection of the geographical location (no coordinate system), and **click “Close”.
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Skip the selection of the input coordinate system, and **click “Close”.
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Preview your image, and **click “Export”.
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Change the pre-selected output coordinate system (Global Mercator), and **click “Change“.
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Select the “Pixels“ tab to adjust the settings of your zoomable image.
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Adjust the tile size, if you don’t want predefined 512x512, and then click **“Set“.
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Select the output format as “Folder with tiles“, then click “Continue“. This option is best for uploading the final image to your own file hosting via FTP. If you select the GeoPackage option, you can upload the image directly to a 3rd party cloud hosting service and serve it to your users from there. More info about hosting is here. Do not try uploading a GeoPackage with a tiled image to MapTiler Cloud, as MapTiler Cloud does not support the rasterized GeoPackage.
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Always make sure to select the output format as “Folder with tiles“, then click “Continue“.
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Adjust the zoom levels and select (if you want to ) the “HiDPI tiles” option, then click “Continue“.
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Choose your output folder and name it accordingly, then click “Continue“.
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Wait for the rendering process to finish.
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Review your tiled image processed by MapTiler Engine, when done, click “Open folder” to open the target folder with rendered tiles.
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Each zoom level has a dedicated folder with raster tiles generated from your original image.
Conclusion
When done rendering, you have to choose how to publish your newly generated zoomable image.
If you exported to a folder with tiles, you can upload them via FTP to any web server and serve with leaflet.html or openlayers.html prepared viewers.
Useful links
Folder vs. MBTiles vs. GeoPackage
Web and custom map hosting
How to upload a tileset to MapTiler Cloud
Retina - HiDPI tiles