Digital Publishing is becoming all the rage. Adobe has been adding features into InDesign which are extending the reach of your content. No longer is InDesign limited to a paper medium. Publishers are looking to produce their printed content in the form of digital magazines or electronic books.
An ePub (Electronic Publication) file is a free and open e-book standard. ePub files end with a .epub extension. They support re-flowable (word wrap) and re-sizable text, inline raster/vector images, metadata and DRM support. They can be viewed on any device that supports the epub file format. Devices include the iPad, NOOK Color, and Sony Reader. Click here to see more ePub readers/applications.
In InDesign CS5, you can export your document as an ePub file by choosing File > Export For > ePub.
Tips for creating ePub Files
Once you have set up your InDesign document, review the following tips to help ensure your file is exported properly to the EPUB format. Note that these are general tips to make sure your EPUB file can be opened and read by any one of the more than 50 devices or software programs that read the EPUB format.
InDesign exports all your text frames as one single flow of text, even if the frames are not threaded together, based on their position on the page. For the most control over the order of the content, either thread all the frames together in the order you want the text to appear in the EPUB file (pasting image frames and groups into the text flow as anchored objects), or apply XML tags to all the content and then use the Structure pane to select elements and drag them in the desired order. Master page items, empty frames, and frame attributes such as stroke and fill are not included in the export.
When converting an EPUB file, InDesign retains basic text formatting by converting paragraph and character styles into an automatically generated CSS file. To fine-tune the appearance of the text in your EPUB file, you will need to edit the CSS file after conversion. If you need to create white space in an InDesign document that you will be converting, use the Space Above, Space Below, and Indent settings in the Paragraph Styles dialog box. White space created with empty carriage returns, multiple spaces, or tabs are ignored in the EPUB output. If your InDesign document contains local formatting (for example, a manually formatted word that doesn’t have a character style applied to it), select the Preserve Local Overrides option (in InDesign CS4, Local Formatting Under Base for CSS Styles) in the Contents category of the Digital Editions Export Options dialog box. If you’re using InDesign CS3, InDesign preserves only character styles, paragraph styles, and object styles during export.
If you are working with a long document with an expected final file size over 300KB, you will want the EPUB document to have a separate file for each chapter. In InDesign CS3 and CS4, you will need to break each chapter into a separate InDesign document and then create an InDesign book (File > New > Book). In the new Book panel, add the individual chapter documents, and then select Export Book for Digital Editions from the Book panel menu.
You can use the same method in InDesign CS5 (using the Export Book to EPUB command), but if you’re starting with a single long document, it’s not required. First, create a table of contents and specify the paragraph style used for chapter titles as the first level in the table of contents. Then, to have InDesign automatically split the EPUB file into separate files for each chapter during export, select the Use First Level Entries As Chapter Breaks option in the Table Of Contents section of the Digital Edition Export Options dialog box.
In general, all fonts used in a document can be embedded in the resulting EPUB file by selecting Include Embeddable Fonts in the CSS Options section in the Digital Editions Export Options dialog box. Note that although EPUB supports font embedding, iBooks does not. Consequently, even if you turned on this option, you will see the standard iBooks font in your final document when it’s displayed on the iPad. Users can choose to view the book with any of the other fonts iBooks offers instead.
The EPUB file specification requires that images be converted to GIF or JPEG. InDesign CS5 automatically exports an optimized version of each image that displays well on most eBook readers and is small enough to avoid performance and memory issues. In InDesign CS3 and CS4, choose Optimized from the Copy Images menu in the Digital Editions Export Options dialog box to convert an image to GIF or JPEG, and reduce the file size by downsampling. In all three versions, you can select the Formatted option in the Digital Editions Export Options dialog box to preserve formatting that you have applied to your image frames, such as stroke, fill, rotation, shear angle, and any cropping you have done. You will also want to anchor your images to the relative area to which they belong in the text, or all of them might move to the beginning or the end of the document. If you want to use custom image positioning, you may need to edit the CSS file in the EPUB file after export.
Metadata (information about the file itself) that you add to an InDesign document is retained in the EPUB file and used by eReader devices and software. To add metadata in InDesign, make the document active (if you’re using the Book feature, make the Style Source document active) and choose File > File Info. At a minimum, add the title of the book in the Document Title field, otherwise some eReaders won’t even be able to open the EPUB file. You may optionally include other information such as author, description, keywords, and copyright status*.