Cover Generator Changes DPI

I uploaded an 5.5 by 8.5, 300-dpi image to the cover generator. However, the resulting file fails when converted to PDF/1X, saying that the image is now 292.57, which will not upload without errors to IngramSpark. In addition, the ISBN box comes in at 287. rather than 300.

How can I fix this?

More information is the following:
The cover generator wants the image for the 5.5 by 8.5 book to be 1688 by 2625

When I upload that image, or any other similar size, it scaled the image to be 1646 by 2560 which then is no longer correct for 300 dpi. So the real question is why it is scaling the image?

Since version 5.3, WordPress detects big images during upload to the media library and applies a scaling. The default threshold is 2560px, and will be applied to both the height and width, and the image will be scaled down. This scaled image will be used as the largest available size. The original image will be stored too but is not used.

In the book info page, there is no way to switch to a text mode to remove _scaled from the cover filename to link to the original file that is also stored on the server. So, I have no solution for the problem.

@t.dumm is correct about what’s happening. We have filed this as a bug and will attempt to fix in a future release:

Thank you, Pressbooks. The current work-around for me was to generate the cover, and then use Adobe Acrobat to replace the scaled image with the full-size image. Somewhat of a pain, but better than starting from a blank page!