In creating PDF flip books – supporting retina displays without crippling the browser

28 October 2013

While the iOS platform provides a excellent platform for publishing documents, it also presents a number of problems due to its limitations in memory and CPU. Providing a clear zoom without having to have the end user download very large documents can be a rather tricky problem to deal with. For example, there are limitations to both file sizes as well as image sizes in iOS as outlined by Apple’s developer guidelines.

FlexPaper Zine 2.1.8 implements a new method of sharpening text and image quality further on touch based devices. By creating a grid like structure over the document, the viewer determines what parts of a visible page that needs to be downloaded and downloads only these segments of the page in high resolution. 

To use this new method, simply tick the “optimize publication using PHP” checkbox when publishing your document from the desktop publisher app. 

Have a look at a example PDF document which has been converted to a pdf flip book with support for the grid high res loading method

This method currently requires the server you use to host your documents to support PHP5 (or higher) together with GD.