Tweaking ePubs (5): Make it quick with a right-click

Making minor changes to existing EPUB files is easy with our free tweak_epub utility. You just launch the utility, direct it to an EPUB file of interest, and make desired changes.

If you need to modify EPUB files only occasionally, launching the utility manually, then browsing your disks for the EPUB file of interest could not be a problem. But if you need to edit many EPUB files, getting through this procedure for each EPUB file might be tiring.

So we have slightly modified the tweak_epub utility to make it more practical. You can now use the Windows Explorer "Open With" right-click command to open any EPUB file straightaway in the tweak_epub utility. This will be particularly useful if you often tweak EPUB files.

So how do you go about this?

1) First, click the following link to re-download the utility:

http://www.AtlantisWordProcessor.com/download/tweak_epub.exe

As before, you can download to any folder on your hard disk, and the utility still does not require installation. To run the utility, simply run the downloaded "tweak_epub.exe" file.

2) Right-click an EPUB file of interest in Windows Explorer.

3) Choose the "Open With..." command from the menu if it is available:


Otherwise, click the "Choose Program..." command:


4) Press the "Browse..." button in the "Open With" dialog:


5) Direct the "Open With..." dialog to the disk folder where you downloaded the tweak_epub utility, and double-click the "tweak_epub.exe" file:


6) Press the OK button in the "Open With" dialog:



From then on, Windows will show the "tweak_epub" command in the "Open With" menu whenever you right-click an EPUB file for editing:


Choosing the "tweak_epub" command will immediately open the selected EPUB file in "Tweak EPUB":

Tweaking ePubs (4): Choosing a text editor

We discussed earlier in this blog the tweak_epub utility that you can use to make minor changes to EPUB files. This utility automatically used the standard Windows text editor Notepad to edit the files contained in EPUB packages.

A number of people using this utility said they would like to be able to choose a different text editor. This is now possible in the new version of the tweak_epub utility. Click this link if you want to download it:

http://www.AtlantisWordProcessor.com/download/tweak_epub.exe

When you run the updated utility, you'll see a new button, "Choose Editor...":


Press this button to choose another text editor. Note that you have to select the executable file of the text editor. Executable files have the ".exe" extension. For example, the executable file of the Windows Notepad editor is "notepad.exe".

Optimizing PNG images

You might say "Who cares about file size nowadays? Modern PCs have hard disks with zillions of bytes of capacity. Why bother with file size optimization?"

It is true that modern hard disks have a much larger capacity than, let's say, 15 years ago when a 1 GB hard disk was considered a luxury. Today even USB flash drives have a larger capacity. But there are cases when file size really matters.

It might be the case if you run a Web site. In most cases, you've subscribed to only a limited monthly bandwidth. Now if your site has only a few visitors a day, probably your bandwidth limit is irrelevant. It will hardly be ever exceeded. But if your site has hundreds or thousands of visitors a day, the weight of your files might be critical. Let's suppose that your site harbors a 1 MB picture. If it gets viewed 100 times, this will add 100 MB to the traffic of your site. 1,000 views will generate an extra gigabyte of traffic. What if it gets viewed 10,000 or even more times? It isn't hard to imagine how many gigabytes of your allowed bandwidth will be eaten up. This is why optimizing graphic files saves site traffic. This in turn might allow you to switch to a cheaper Web hosting plan and save you money. Optimized pictures will also load faster in your visitors' Web browsers, and browsing your site will be all the more pleasant.

Having optimized graphic files in the eBooks or documents you create might also be important to spare download time to readers.

Now how can you optimize picture size?

Pictures already included in documents can be optimized in Atlantis by reducing their quality. But graphic files can also be optimized directly on your hard disk using OptiPNG by Cosmin Truţa. This free utility shrinks PNG image files (PNG being one of the most popular image formats among Web site designers). OptiPNG performs lossless optimization of PNG files, plus it can convert images in other formats (BMP, GIF, etc) to optimized PNG.

OptiPNG is a command-line (console) application for Windows. You can download it directly from its home site:

http://optipng.sourceforge.net/

But there is a more convenient way to use this utility. A special setup file of OptiPNG created by Dmitry Vlasko not only installs OptiPNG on your system, but also integrates it into the Windows shell. Pictures can then be optimized directly in Windows Explorer by right-clicking their filenames. You'll find this setup file at the OptiPNG Windows shell integration home page.

Here are full instructions on how to install and use this utility:

Click the following link to download the SetupOptiPNG.rar compressed file:

http://dms-journal.ho.ua/storage/software/OptiPNG/SetupOptiPNG.rar

Then extract SetupOptiPNG.msi from SetupOptiPNG.rar, run it, and follow the onscreen instructions.

To adjust the OptiPNG settings, use the "Start > Programs > OptiPNG Settings" shortcut.

To optimize any PNG image on your hard disk, right-click it in Windows Explorer, and choose the "OptiPNG: default profile" menu command:



What could be more convenient?

Tweaking ePubs: It's just a ZIP file!

Did you know that any eBook in the EPUB format is just a ZIP file but with the .epub file extension? EPUBs normally contain multiple files in different formats: XHTML, XML, JPG, etc. If you rename any .epub file to .zip, you can open it in any file compression software.

Since Atlantis automatically generates all the required EPUB components, and puts them into a ZIP file in the proper order, you do not necessarily need to know what's inside your EPUB books generated by Atlantis. But if you are familiar with the EPUB specification, at times you might need to make minor adjustments to your EPUBs not possible directly through the GUI of Atlantis.

So how to modify individual files within the EPUB package?

Since EPUBs are actually ordinary ZIP files, you can change their file extension to .zip, and open in your ZIP software. Then extract files of interest, modify them in a text editor, and put back in the ZIP file. File extension has to be changed back to .epub.

But there is one important detail to remember when you modify an EPUB file in a ZIP software. The first file in any proper EPUB package must be "mimetype". It is always a 20-byte ASCII file containing this string of text:

application/epub+zip

Even more, this file must be always stored within the EPUB package in uncompressed form.

So before tweaking your EPUB files with a ZIP software, you should be sure that it will preserve the original order of files, and leave the "mimetype" file uncompressed. Not every ZIP software will allow such "delicate" changes to a ZIP file.

But we can suggest an alternative solution to EPUB tweaking. The tweak_epub utility will allow you to adjust any text file from an EPUB package in a quite convenient way. You can download this utility from our site. Just click the following link:

http://www.AtlantisWordProcessor.com/download/tweak_epub.exe

and download a small file "tweak_epub.exe" (~100 KB) to any folder on your hard disk.

This utility does not require installation. Just run this "tweak_epub.exe" whenever you need to tweak an EPUB file.

It will display the "Open EPUB" window:



Direct it to the EPUB file of interest, and click "Open".



It will display another window with a complete list of files contained within your EPUB:



Click a file that you would like to modify (on the below screen capture – a file with CSS styles), then the "Edit File..." button:



The selected file will be opened in Notepad:



When you are done with editing this file, click the cross button in the title bar of Notepad, or press Alt+F4. You will get a confirmation message from Notepad:



Click "Yes" if you want to save changes.

The "Save Changes" button of the "tweak_epub" utility will become enabled:



You can click this button to complete editing the EPUB file, and save all the modified text files back to the EPUB package. Of course, you can always click the "Cancel Changes" button if you do not want to save changes to the EPUB file.

By the way, it is recommended to make a copy of the original EPUB file before tweaking it. Just in case you make an editing mistake.