Error converting EPUB to MOBI

[picardo]

Hi there,

When I try to convert EPUB files into MOBI files before sending them to my Kindle DX, it takes an unusually long time on Calibre, and at the end it fails with this error message:

Python function terminated unexpectedly
string index out of range (Error Code: 1)
Traceback (most recent call last):
File "site.py", line 103, in main
File "site.py", line 85, in run_entry_point
File "site-packages\calibre\utils\ipc\worker.py", line 99, in main
File "site-packages\calibre\gui2\convert\gui_conversion.py", line 24, in gui_convert
File "site-packages\calibre\ebooks\conversion\plumber.py", line 898, in run
File "site-packages\calibre\ebooks\mobi\output.py", line 182, in convert
File "site-packages\calibre\ebooks\mobi\writer.py", line 367, in __call__
File "site-packages\calibre\ebooks\mobi\writer.py", line 380, in _dump_stream
File "site-packages\calibre\ebooks\mobi\writer.py", line 395, in _generate_content
File "site-packages\calibre\ebooks\mobi\writer.py", line 1336, in _generate_images
File "site-packages\calibre\ebooks\mobi\writer.py", line 123, in rescale_image
File "site-packages\PIL\Image.py", line 653, in convert
File "site-packages\PIL\ImageFile.py", line 189, in load
File "site-packages\PIL\PngImagePlugin.py", line 349, in load_read
File "site-packages\PIL\PngImagePlugin.py", line 92, in read
File "site-packages\PIL\PngImagePlugin.py", line 40, in i32
IndexError: string index out of range

[kovidgoyal]

is this with all epub files?

[picardo]

Just the ones I converted from HTML using Calibre.

[picardo]

Btw, when I try converting them using Mobipocket Reader, it also fails.

[picardo]

Oh, I forgot to mention. When I convert directly from HTML into MOBI--as in when I plug in the device before hitting send to device, which takes them directly from HTML to MOBI--the file that gets sent is full of problems, like you can't go to the next page on some pages and there are many completely blank pages. Things like that. That was my initial reason for converting into EPUB before sending them to the device.

[picardo]

One last update: I kept it running to see if it could work eventually. After 10 minutes, it finally sent the book to the device. Maybe the size of the book (10MB) has something to do with the long delay, but it had failed the last time I tried this. Ther are still problems with the output, as I mentioned above, "next page" button is not working at some places, etc.

[picardo]

I think it's the size or the number of the images in this file causing the issue. I cropped out a number of images and it went through eventually.

[kovidgoyal]

Yes, the error indicates aproblem with one of the PNG files in your book.

[picardo]

Originally Posted by kovidgoyal

Yes, the error indicates aproblem with one of the PNG files in your book.

You know what? I think one of the images has the wrong extension. I started opening all the images after reading your reply, and IrfanView told me one of the JPGs was supposed to be a PNG.