I'm making by myself an ePub book. In this book I put some screenshot as a PNG image inside an XHTML page. So in the content.opf I referenced the XHTML page...
Until few days ago it worked: the XHTML with PNG image was showed.
Now I see only a blue question mark at the place of the PNG image preview. But if I double tap onto the question mark, the preview correctly shows the PNG image.
This happens in IBooks and Stanza, but not in GoodReader and others eBook readers...
An tips?
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Every PNG is ~200Kb and its dimension is ~2500x2500 with 300 dpi.
I don't know if thew problem is the dimension or the image format.
Well, your images are too big for a start. Apple state that the maximum pixel size of an image on a page is 2 million pixels. So 6.25 million pixels might be a bit of a problem.