Readium hangs when loading ePub

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I have a valid normal ePub3 file and which is displaying properly in iBooks but is not loading in Readium. It hangs after loading few files. Could you please help me to resolve this issue?


Does the import work if you unzip the EPUB and use the folder import option in Readium?

See the issue noted in the "Important notice for Readium users" here:



Yes, sometimes unpacking solves the extraction issue.

However, even when loading from unpacked directory, I get the following error: "ERROR: while writing to filesystem", especially for large EPUB 3 files (~150-200 MB) with hours of audio.

I went to the source code (extractBook.js) and that message seems to suggest that the extraction fails because FileSystemApi fails.

Going to the source file fileSystemApi.js, you will find a not really nice line:

var FILE_SYSTEM_SIZE = 1024 * 1024 * 80; // ~ 80 megaBytes

which seems to limit the size of the eBooks you can load into Readium...

Dear Readium developers, can you please remove this arbitrary limit?

Curioser, curioser: I have a ~500 MB EPUB 3 file, unpacked. It is loaded into the Readium library on Windows and Mac OS X, but my Debian box refuses to load it and throws the error mentioned above: "ERROR: while writing to filesystem".

Any (non-null) pointer will be appreciated, thanks in advance.

I am having a similar problem with a 216 MB file with MP4 videos (encoded using h.264). The ePub passes " Epubcheck Version 3.0.1 Validating against EPUB version 3.0
No errors or warnings detected".

Previously with Chrome version 39.0.2171 and Readium version 2.15.2 the ePub loaded OK using MAC OS 10.7.5. However 2 of the 21 videos did not play when I loaded the file from a local directory. (I was told by a developer that I was working with that the ePub loaded normally and the videos played on Windows and Linux when loaded from the local directory). If I unzipped the same ePub file, using ePub UnZip 1.0, and loaded the unzipped folder on the MAC using the Readium load "unpacked directory" option the file loaded and all the videos played. When I zipped the same directory using ePub Zip 1.0.3 and loaded it using the "local directory" option the file behaved the same as the original - it loaded but two of the videos didn't play.

With Chrome Version 40.0.2214.111 (64-bit) and Readium version 2.15.2 on the same MAC, using the same ePub file, when loaded from a local directly the Readium Library screen goes blank, to include the removal of a previously loaded small ePub that was in the Library. When I again unzip the large ePub file and load the unzipped folder using the "unpacked directory" option the file loads normally and all the videos play.

Some of my clients have tried loading the ePub from the local drive using Windows and the file seems to hang/not show in the Library.

I have sent an email to rkwright with a link to the problem ePub file.

Yes, this problem was real with some very large EPUBs with large and/or many audio/video assets. This bug has been fixed and is in release 2.18.1 (released 30 April 2015)

I think the problem has not entirely gone away. Attempting to load a 700 MB ePub3 with videos, the load hung on the last 8 files, the videos, it seems. Unpacking the ePub had Readium loading it very quickly and completely.

Videos play, but full-screen option is not available. Full-screen viewing doesn't work at all. If I follow a link, there is not an obvious way to step backwards to the page just left. This makes it tricky to take the reader to the Glossary, as they have to navigate back to the reading point.

Radium 2.18.2, Mac MBP 2013, 16 MB RAM, OSX 10.11 (El Capitan)

Can you post the offending EPUB somewhere (like DropBox) so we can take a look?

Thanks, Ric Wright

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