Gen3 crashes while reading PDF

[David B]

Hi,

I just received my Gen3 a few days ago and already encoutered problems when reading several pdf files. When I reach a given page, the Gen3 would simply restart. This bug is reproductible.

Here is one of the pdf where I encountered the problem. Could another Gen3 owner try to read this file and see if he can read the second page?

Thanks.

[tompe]

I have reported a couple of these bugs to Bookeen and sent them the file that was problematic. You should probably report it so they have more test cases.

[David B]

I tested another bunch of PDF files and managed to reproduce the crash several times. It seems that the problem is due to huge embedded pictures. I Will report it to bookeen now.

[laborg]

I'm sufffering from the same problems. Lets hope on the next firmware realese...

[Snuffi]

The crashes when reading PDFs happen pretty regularly for me. Generally, I can say that the larger the file and the more graphics it includes the more likely it is to crash. There have been exceptions, though, I also had crashes with rather small files.
I have had some moderate success when converting PDFs to prc with Mobipocket creator but that solution has two big shortcomings:
1) Some PDFs I couldnt convert -> Creator would create an empty file even though no error occurred (reproducible)
2) All Graphics which contain text (like screenshots) are way too small after the conversion but as it is no longer a PDF there is no zooming or panning. This is not the fault of the software, of course, and the result was to be expected. Nonetheless it makes converted of PDFs in those cases practically unusable.

[mbovenka]

Originally Posted by Snuffi

The crashes when reading PDFs happen pretty regularly for me. Generally, I can say that the larger the file and the more graphics it includes the more likely it is to crash. There have been exceptions, though, I also had crashes with rather small files.
I have had some moderate success when converting PDFs to prc with Mobipocket creator but that solution has two big shortcomings:
1) Some PDFs I couldnt convert -> Creator would create an empty file even though no error occurred (reproducible)
2) All Graphics which contain text (like screenshots) are way too small after the conversion but as it is no longer a PDF there is no zooming or panning. This is not the fault of the software, of course, and the result was to be expected. Nonetheless it makes converted of PDFs in those cases practically unusable.

Mobipocket Creator does seem to have an issue with some PDFs; I get 'Import failed!' when I try to import them. I haven't as yet figured out what they have in common.

As far as the small pictures are concerned, you might want to try the 'Embed JPG' (or something like that; I'm not at my PC right now) option in Creator, or the '--jpeg' option of Mobigen. When you do that, it will use JPEG images in the built book, and not convert them to GIF first. As JPEG is (most of the time anyway) more compact than GIF, for a given picture file size the resolution can be higher.

Regards,

Marco.

[laborg]

This is the email I received concerning the pdf troubles on the cybook.

We are aware of such issues and are working on improving the software.
Nonetheless, please send us a couple of sample files so we can integrate
them into our test suite and make sure the issue is clearly identified.

For your information, we have scheduled to release at least 1 firmware
upgrade this quarter. Please note that we cannot ensure yet that your
specific issue will be solved by the very next update.

With our best regards,
Bookeen Support Team

[David B]

Good news. Thanks for the info.

[slayda]

Originally Posted by mbovenka

As JPEG is (most of the time anyway) more compact than GIF, for a given picture file size the resolution can be higher.

Regards,
Marco.

This is not exactly true. JPEGs are generally smaller than GIFs from the same original. GIF's are 8 bit and use a lossless compression. JPEGs can be 24 bit but, except at the highest quality which is not usually used, is a lossy compression. This can be seen if you start with a 24 bit, uncompressed TIFF and change it to JPEG and back to uncompressed TIFF and iterate on this several times. Each conversion to JPEG loses a little and it accumulates.

On the other hand, if the original is 24 bit then the first compression to GIF loses 16 bits of color resolution.

Bottom line - if you start with an 8 bit image then GIF is better and if you are iterating in the compression of a JPEG, it is bad. But for a single compression of a 24 bit original, JPEG can be better quality and usually results in a smaller output file.

Maybe more than you wanted to know about GIFs & JPEGs.

[slayda]

I have had problems with the text conversion from PDF to PRC using Mobipocket Creator. I use PDF Converter Assistant by Nuance. It converts PDF to RTF which I can then use Mobipocket Creator to convert to PRC. The results are much better (text wise) than just straight Mobipocket Creator. Cost is $49.99. I have the Professional version for $99.99 which includes PDF Converter Assistant and two other (almost never used) programs.

So far I haven't tried it with images in the PDF file.

[DaleDe]

Originally Posted by slayda

This is not exactly true. JPEGs are generally smaller than GIFs from the same original. GIF's are 8 bit and use a lossless compression. JPEGs can be 24 bit but, except at the highest quality which is not usually used, is a lossy compression. This can be seen if you start with a 24 bit, uncompressed TIFF and change it to JPEG and back to uncompressed TIFF and iterate on this several times. Each conversion to JPEG loses a little and it accumulates.

On the other hand, if the original is 24 bit then the first compression to GIF loses 16 bits of color resolution.

Bottom line - if you start with an 8 bit image then GIF is better and if you are iterating in the compression of a JPEG, it is bad. But for a single compression of a 24 bit original, JPEG can be better quality and usually results in a smaller output file.

Maybe more than you wanted to know about GIFs & JPEGs.

You do not lose 16 bits of color resolution in converting to Gif. What you lose is a limit to the maximum number of colors that can appear in the image which is limited to 256 different colors. The colors themselves are defined in a palette that is 12 bits I believe so it supports 4096 different colors.

Dale

[slayda]

Originally Posted by DaleDe

You do not lose 16 bits of color resolution in converting to Gif. What you lose is a limit to the maximum number of colors that can appear in the image which is limited to 256 different colors. The colors themselves are defined in a palette that is 12 bits I believe so it supports 4096 different colors.

Dale

Actually the color palette is 24 bits, equating to approximately 16 million colors. (The color map consist of up-to 256 sets of 24 bit colors - 8 each of RGB.) But as you stated you can only use 256 of them. This is perfectly adequate for cartoons and simple drawings but not for complex images such as a person's face or a rose arrangement. However that being said, your color resolution is 8 bits or 256 colors. And yes it is different from spacial resolution and is usually not stated as resolution. That's just the way I think of it.