DjVu Reader for iPad and iPhone

(last updated: 28.07.2014)
current version: 2.0.10
dev version: 2.0.11

Content

Capabilities

DjVu Reader is a simple application for iPad that allows to display mainly DjVu documents. It is aimed at being practical and at browsing easily through the documents. With time, its goal has increased and now DjVu Reader can read the following file formats It has many features

The interface

Appearence

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Browsing a document

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Searching for a document

You can search for a document in your directory structure. The search toolbar is normally hidden at the top of the document table. Tapping once on the statusbar or pulling the documents table down will reveal the search toolbar. Just insert a string for the document filename you are looking for and hit Search. All files containing that string in their filename will show in the table. Only files in the directory structure under the current directory will be looked at. Hitting the Cancel button will display the current folder content again. You can delete the files directly from the Search Result displayed.

if Many strings are looked for, only files which filename contains all those strings are displayed.

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The Documents Menu

In the Documents Menu you can see all your files.

You can manage the directory structure through the Documents Menu.

The name of the current folder is written in large characters at the center of the navigation bar of the document menu. The upper folder name is written in the left button of the navigation bar. Clicking on that button changes the current directory to the upper one. Selecting the Edit mode, you can

The tools are, in order, cut, copy, paste, new folder, rename, delete, refresh content.

When selecting New Folder, or Rename, a dialog appears in which you can type in the new name.

In the New folder dialog, the name of the current folder in which the new folder will be created is written above the input line.

In the Rename Dialog, the current name of the file is written above the input line, and also into the input line to ease the modification of a current name.
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The Outline Menu

If the opened document contains an Outline, the outline is loaded and the icon turns blue . On first opening the outline, the icon turns black again, but the outline will still be available.

You can edit the outline or create a new one. Just go tho the page you want reference. Click the Edit button and select the add button (plus). That will create a new item that contains the new reference with the page number displayed. An edit dialog will show in which you can change the name of the reference. Do not leave the item with an empty name, that will give a corrupt outline and may crash the application.

You can copy a complete outline from one file to another. Select and open the file you want to copy the outline from. Scroll down the outline, select Edit and then copy. Open the destination file. The previous outline is still in memory and the outline of the current file is not loaded. Now select the outline menu and push the save button. That will save the current outline (the one from the previous file) into the current file (the old outline will be completely replaced).
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The Bookmarks Menu

You can store bookmarks for PDF and DjVu documents. Bookmarks are not stored into the document. They will be available, though, into DjVu Reader. You can create bookmarks for PDF documents that do not have outline informations, for example. Or you can simply use the bookmark feature to record...bookmarks, for interesting pages. Just give the bookmark a name that is representative enough. Bookmarks are stored as soon as they are created or modified.
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In Document Search Menu

You can search for words in DjVu documents. Open a DjVu document and press the looking glass button. It will open a popover table view, with a search controller. Type in the word you are looking for. All pages with occurences of that word will show in the table, with the number of occurences on the page. That feature depends highly on the quality of the OCR layer stored in the document. Also the recognition of the position of the word on the page is also given by the document itself. So if some occurences are not found or if the colored boxe showing the occurences are misplaced, that is because it is not stored correctly into the document. Later revision will allow to search for strings. That feature is not yet available for PDF documents.
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EPUB Support

EPUB documents are now supported by DjVu Reader. They can be read directly by selecting a document, though the prefered method is to put all your EPUB document in the same temporary folder (say "temp") and THEN rename it "ePub" (case is not important). Once this is done you will benefit from a complete environment that deals with your EPUB library, where you can modify the author, title fields and save them back to the original epub files. The best method to create the "ePub" is still using the FTP server of DjVu Reader. From an FTP client on your desktop you can create an "ePub" folder and copy there all your EPUB files. Once in the "ePub" folder, you don't see anymore your EPUB files (unless you change the name of the folder to omething else that EPUB). When you click the "ePub" folder you enter directly into the EPUB mode. Where a friendly interface allow you to browse through your library. If you make any change to an epub document while in the library, that change will be stored back into the original file. So if you move that file to another app, the changes will appear in the new app too. That allow to correct badly formatted author informations or title, add language informations and so on.

Files transfer with FTP

Provided you are in a WiFi environment, the prefered way to upload document to your iPad is to use the integrated FTP (File transfer protocol) server which is very efficient and maintain the directory (folder) structure you may have on your desktop computer. To do so, start the FTP server using the "FTP" button. The address and port of the iPad FTP server is displayed. You can then use whatever FTP client on your desktop to upload/synchronize your hard drive DjVu folder into your iPad. Many free FTP client are available and include Cyberduck©, FileZilla©, SmartFTP©, BitKinex©, and so on.
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Using DropBox

You can use your DropBox account to store, download or upload your files from DjVu Reader. Click the DB icon in the documents menu to link to your account. Once linked you can interact with it as if it was a local folder, with the exception that you cannot read a file directly from your DropBox account. You need to download your file to your local folder first using the copy/paste mechanism. You can download many files at a time (be aware though that it can take a bit of time to download large files depending on your connection quality). You can delete/create folders into your DropBox, as you would with a local folder.

Creating DjVu documents

If you have a PDF document and have the djvulibre library installed with all its tools, you may have a working djvu conversion tool available for free. There is a script named "djvudigital" that can be used to convert PDF files to DjVu format. It uses a Ghostscript driver gsdjvu. You can then open a terminal window, go to your document folder and enter something like

djvudigital filename.pdf --dpi=300 --words --bg-slices=78+10+11+10

and, if all goes well, you should recover a djvu file named filename.djvu. Adding

--gsarg=-s

Uploading DjVu documents

For now you need to connect your iPad to your computer and upload your documents through iTunes. Once your iPad is connected to iTunes, select the iPad icon in the left pane. Then select the Apps tab in the main window. Scroll down the window and under the image showing the iPad screens you have list of Apps that can share files with iTunes. Select DjVu Reader and upload your documents by putting them there.

It is now possible to load a document into DjVu Reader from another app, using the Document Sharing possibility provided by the Apple API. For example you can load a document in Safari, or receive one in mail, and taping on its icon, you will open the document into DjVu Reader. The document will be placed into a folder named "Inbox" in the main Documents folder.
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Downloading Books with Safari

Many books can be found on the internet. Though many sites that provides books for reading as for example http://www.archive.org embbed their document in an applet. For example

http://ia600307.us.archive.org//load_djvu_applet.php?file=26/items/uncletomscabinor00stowiala/uncletomscabinor00stowiala.djvu

To recover the DjVu file you need to suppress the call to the applet in the address, that is the part "/load_djvu_applet.php?file=" sot that it reads

http://ia600307.us.archive.org/26/items/uncletomscabinor00stowiala/uncletomscabinor00stowiala.djvu

Then Safari can download the file and you can open it with DjVu Reader.
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Troubleshooting

If the application cannot start and crashes on launching, you can prevent the encriminated document to be open at startup. Go to the Preferences application and select the "DjVu Reader" item. Select the Reset switch. Next time you start the application, no document will be opened and a fresh session will start.

If a document make the app crash, try deleting the plist of that file in the document menu -> opened window.

If memory is low, it may happen that even if the outline is present it will not show up and a blank outline is shown. The situation will be corrected when enough memory will be available again.

DjVu documents are image based. Displaying images on the iPad can be very resource consuming. Apple suggest not to display images that are too large compared to the iPad display size. In a DjVu document, each displayed page is a true image that needs to be computed before to be displayed. This process can take some seconds to complete. It is a normal process when reading DjVu documents. Some documents are made with larger images than others. So various documents may take different amounts of time to be displayed. Some are displayed quite instantaneously some can take up to 3 seconds to display and even more.
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Wishlist

These are the requested and planed features at the moment (numbers indicates the priority of the planed features, no numbers indicate a possible implementation in a remote future, * indicates a probable implementation in a minor update).
I will try to implement the desired feature according to my possibilities and to the possibilities offered by the DjVu format.
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Bugs and Comments

DjVu Reader can read most DjVu documents. Lately a new DjVu format appeared, aka Secure-DjVu, which encapsulate a crypto-code to protect the document from being read by unothaurized persons. That kind of document cannot be read by DjVu Reader. This is not a bug (neither a feature ;-) : mainly a lack of feature).

When downloading many files from Dropbox, some files seem to be stuck and not downloading. If that happens ignore them and download those files again. they will download fine.

Outlines in PDF documents can be lengthy to load (though it is a background process, so you can browse through the document at once, even if the outlines are not available) due to some outlines formatting that use somewhat indirect references. At the moment this is the way it is, though some improvements may appear in a later release with, ideally, some editing features.

Address any comment or bug report to: info(at)pasacreation.com.
Please do report bugs or comments to the above address. Care is taken to answer all e-mails. Even if corrections or modifications cannot be done at once, I try to take care of all requests. Understand though that this is a part time project, so I will do my best to satisfy all requests but be patient. Thanks in advance.

Known bugs

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Changelogs

Current release: 2.0.10 (13.07.2014) 2.0.9 (03.02.2014) 2.0.8 (27.01.2014) 2.0.7 (30.12.2013) 2.0.6 (26.11.2013) 2.0.5 (20.11.2013) 2.0.4 (20.11.2013) 2.0.3 (15.11.2013) 2.0.2 (09.11.13) 2.0.1 (02.11.13) 2.0.0 1.5.2 (est.:25.06.2012) 1.5.1 (est.:03.03.2012) 1.5.0 (est.:26.02.2012) 1.4.0 (10.10.2012) 1.3.3 (10.09.2012) 1.3.2 (01.08.2012) 1.3.1 (25.06.2012) 1.3.0 (10.05.2012) 1.2.7 (01.04.2012) 1.2.6 (31.03.2012) 1.2.5 (26.02.2012) 1.2.4 (20.02.2012) 1.2.3 (12.07.2011) 1.1.5 (04.07.2011) 1.1.4 (17.06.2011) 1.1.3 (31.05.2011) 1.1.2 (05.05.2011)
1.1.1(25.03.2011)
1.1.0 (05.03.2011)
1.0.2 (21.02.2011)
1.0.1 (17.02.2011)
1.0.0 (15.02.2011) To top of page