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Setting the image resolution in BloomPUBs

Currently, images in BloomPUBs and online reading are down-sampled to a max dimension of 600 x 600 pixels. This is to better serve users who have poor internet and/or limited memory on their devices.

In Bloom 5.4 and 5.5, you can increase this number by following these steps:

1) In the publish-settings.json file for the Bloom book, change "imageSettings":nullto "imageSettings":{"maxWidth":1200,"maxHeight":900} Or whatever number you want.

2) Create your bloomPUB again, or upload to the book to Bloom Library.


Note, images in PDFs are not down-sampled


Bloom normally down-samples incoming images to 3500 x 2550 (landscape) or 2550 x 3500 (portrait). These maxes were chosen to fit A4 paper at 300dpi. This was done to avoid the situation we were seeing where less-technical users were getting gigantic images into Bloom and then having memory problems.