Quite often you can face electronicbooks saved in DjVu format - it is often used to store scanned documents. That's just not all electronic "readers" correctly open this format, unlike the same FB2. Is there a way to convert DjVu in FB2?
Unfortunately, a program that is capable of oneclick to translate DjVu to FB2, does not exist. This is due to the fact that the FB2 format contains information in text form. And DjVu is a graphic format, in fact, a set of pictures combined in one file for greater convenience. "Extract" from the picture text is much more difficult than to make a picture from the text. therefore convert DjVu to FB2 in a few steps.
It will be the easiest way to do this, if the DjVu file has a text (OCR) layer. How can I check this? Open the e-book with any suitable program for reading DjVu and check whether it is possible to perform full-text search on the file (of course, the program should initially support the option of full-text search).
If the OCR layer is present, you need to copytext file to the clipboard, paste it into any text editor, edit it if necessary and save it as a text document (DOC, RTF, TXT, ODT, etc.), and already convert a text document to FB2 using any suitable program.
If the DjVu document consists of "clean" images, without a text layer, the process of converting DjVu to FB2 will consist of several stages. To extract text from the DjVu file, you will need to use the program for optical character recognition - for example, Fine Reader or any other more affordable alternative.
But programs for text recognition are rarely able to directly work with the DjVu format. therefore to start you will need to convert the DjVu file to PDF or TIFF format. To convert to PDF, for example, you canuse a bunch of two programs - WinDjView and PDFCreator. Instead of WinDjView, you can use any other program to read this format (if only there was a print option), and instead of PDFCreator - any other virtual printer.
After opening the DjVu file in the reader, call(Ctrl + P), select the virtual PDF printer from the drop-down list and click OK. The program will take some time to prepare the document pages for conversion. When the save file window appears, enter the name of the book and click OK. Please note that Conversion can take a lot of time and computer resources.
You can also use programs for converting DjVu to other graphic formats (for example, DjVuOCR). The main thing is that in the end you get a document that can be recognized with the help of Fine Reader or another similar program. The recognized text is exported to a text editor, where it can be edited, if necessary, and then the text file is converted into FB2.
So, there is two basic schemes for converting the DjVu format to FB2. If there is a text layer in the book, you need tojust copy it to a text document, and already convert it to FB2. If there is no text layer, the chain will look like this: DjVu to PDF conversion or graphic format → recognition of the resulting file in the OCR program → saving the recognized text to a text file → converting the text file to FB2.
At all, converting DjVu to FB2 is a long and time consuming process. So if you have the opportunity to do without conversion, it is better to leave the book in DjVu format.