A lot of you have used calibre to convert your ebooks between different formats. The calibre conversion system is very sophisticated and has many subtleties. Today I will discuss just a few features that are often overlooked and yet a lot of you may find very useful. The following is the “Convert books” icon in the top main calibre tool bar:
Bulk convert: Calibre allows you to convert books in bulk. You can select a set of books, all of which may or may not be in the same format, and convert them all in bulk to a different format. So say you have a kindle and you have a number of books in EPUB, RTF and PDF formats. You can select them all. Then click the “Convert books” icon or click the little arrow next to the “Convert books” icon and choose the option “Bulk convert”. A new window opens. At the top right corner of the window you can set the output format, which in this case would be MOBI.
calibre allows you to choose various settings for the conversion output. A few of these are discussed below. When you select a book and click the “Convert books” icon in the top tool bar a new window opens. On the left of the window is a menu with a number of entries.
Smart Punctuation: The second entry in the menu is “Look and Feel”. When you select it on the right you will see a number of options to customize the look and feel of the output of the conversion. Under the section called “Text justification” there is an entry called “Smarten punctuation”. When this is selected before the conversion, all plain quotes, dashes and ellipsis are converted to their typographically correct equivalents. For example, plain quotes to curly quotes. You can do the reverse by clicking “Unsmarten punctuation”
Page Setup: The fourth entry in the menu is “Page Setup”. This option allows you to optimize the conversion output for a particular device, specifically the image sizes so they fit well on the screen of the device. So say you have a Kindle, then you would choose “Kindle” in the list of “Output Profiles” that appear when “Page Setup” is selected. Say you have converted all your ebooks for your Kindle and stored them that way, and now you have bought an iPad. To optimize the output for ebooks converted to EPUB for the iPad from MOBI for the Kindle, select “Kindle” in the list of “Input Profiles” and “iPad” in the list of “Output Profiles”.
Covers and Metadata: The fifth entry in the menu is “Structure Detection”. When you select it on the right side you will see the option called “Insert metadata as page at start of book”. Selecting it will include the metadata at the beginning of your ebook itself, including reviews if they are available. Suppose you do not want to convert the ebook to a different format but want to include the metadata and cover within the ebook, then just select the same formats for the input and output during conversion with the “Insert metadata as page at start of book” option checked. See figure below for an example. The metadata along with a choice of covers for an ebook can be obtained by selecting the ebook and clicking the “Edit metadata” button in the top main calibre tool bar.
Some ebooks have an image as a cover which is not explicitly marked as the cover. Instead it is just another image in the ebook. In this case when you convert the book in calibre, the output may have two covers. If this happens, re-do the conversion with the “Remove first image” option (above the “Insert metadata as page at start of book”) selected. This will give you an ebook with just one cover.
MOBI Table of Contents: For the specific case of converting to MOBI, the eighth option on the left menu is “MOBI output”. For MOBI output calibre generates a Table of contents (TOC), which is inserted by default at the end of the ebook. When the “MOBI output” option is selected in the left menu you can choose “Do not add Table of Contents to book” if you do not want the TOC or choose “Put generated Table of Contents at start of book instead of end” if you want the TOC at the beginning of the book. The TOC calibre generates is hyperlinked to the chapters.