Black horizontal lines in pdf viewer

[yokos]

I have a lot of djvu files, I converted one by printing it to pdf. Viewing this file on iLiad it badly disappointed: ugly black horizontal lines are visible are all-over. Have a look at attached pdf-file; I will post a picture tomorrow.

I found out: the pages in pdf file are split in several horizontal image parts. The viewer of iLiad shows between a split a black line.

This is a great bug.

Now I have to find a converter which converts all pages of a djvu file to an image format at once to get a clean pdf file.

[haraldb]

I experienced a similar problem. When viewing a from djvu converted pdf with acrobat 6.0, those black lines were present, but when viewing it with acrobat 7.0, they were gone. Probably the pdf viewer on the iLiad is still in the "state" of acrobat 6... Which version of acrobat did you use to generate the pdf?

[b_k]

Originally Posted by yokos

I have a lot of djvu files, I converted one by printing it to pdf. Viewing this file on iLiad it badly disappointed: ugly black horizontal lines are visible are all-over. Have a look at attached pdf-file; I will post a picture tomorrow.
...
Now I have to find a converter which converts all pages of a djvu file to an image format at once to get a clean pdf file.

i would say this is rather a PDF-Bug then the iLiads Software. Evince on Ubuntu doesnt like it either, obviously.

[yokos]

Originally Posted by haraldb

I experienced a similar problem. When viewing a from djvu converted pdf with acrobat 6.0, those black lines were present, but when viewing it with acrobat 7.0, they were gone. Probably the pdf viewer on the iLiad is still in the "state" of acrobat 6... Which version of acrobat did you use to generate the pdf?

Mmmh, I used Acrobat 7 for printing in Lizardtech's djvu viewer. yepp, in Acrobat 7 this splits are invisible, I haven't tried it to watch it in GSView yet.
In Acrobat you can use the Touch-up Tool to move the different image splits.
I just don't know: Does the djvu-viewer split the images or the pdf encoding process?

Exporting djvu pages to bmp [256 colours, stupid for b&w images ] in djvu-viewer & decreasing colour detph to 2 & converting them to pdf [images encoded as old fax standard] works.

[yokos]

This is how it looks like:

[Antartica]

Originally Posted by yokos

I have a lot of djvu files, I converted one by printing it to pdf. Viewing this file on iLiad it badly disappointed: ugly black horizontal lines are visible are all-over. Have a look at attached pdf-file; I will post a picture tomorrow.

I found out: the pages in pdf file are split in several horizontal image parts. The viewer of iLiad shows between a split a black line.

This is a great bug.

The problem is that you have created a "version 1.6 pdf", and xpdf, that is the program the iliad uses for displaying pdfs, imlements only up to version 1.5. b_k uses evince that is based around poppler, and poppler is xpdf converted into a library, so it has the same limitations.

If you are able to get a bunch of image files (one per page), using ImageMagick convert utility you can get a nice pdf (perhaps with a little of fidling to get the right scale factor) from those files. It's as simple as in (tested on Linux):
prompt> convert '*.jpg' result.pdf

If you have to scale the images:

prompt> convert -geometry 200% '*.jpg' result.pdf

NOTE: In the tests i've done, it doesn't seems to compress much the images, so watch out the resulting file size.

[b_k]

wouldn't a better option be to simply set the Compatibility in Adobe Acrobat (or whatever software yokos used to generate the PDF) to PDF Version 1.5?

[yokos]

Thanks, Antartica. So I will try first [on my to-do list on top] to create pdf files in version 1.5 [status quo of Acrobat 6]. Then I will see.

Yes I have known ImageMagick, but it doesn't support djvu as native format, as you already said.

@ b_k: Exactly this will I do!

Other idea: Perhaps the iLiads pdf viewer can't handle tifs encoded in 1 bit CCITT Group 4 correctly.

This evening I will be wiser.

[yokos]

Setting compatibility to 1.3 doesn't help: what I get is a odd look - one half of page is free of black lines, the other not. This is strange!

I do it now this way:
# printing as pdf-file [images: tif as b&w bitmap fax encoding].
# exporting pdf pages as tif [one image per page]
# reimporting tif files as a new pdf file.
This a very odd method, but it's working.

[Constantine]

A bit late comment. Also having the same problem with black lines, with a little search i found that there is nothing wrong with acrobat but with djvu viewer.
So i tried windjview and irfanview and both produce clean output without black lines.
cheers

[pragya105]

I am having these lines in the horizontal view of my new kindle 3 , is there a way to correct this?

[Mackx]

Originally Posted by pragya105

I am having these lines in the horizontal view of my new kindle 3 , is there a way to correct this?

Hi pragya105,

You, posted your message in the iRex-part of the forum, although the effect on the screen looks simular, I think you will get more response when posting in the Kindle-part of the forum.

Good luck with fixing your problem.

[pragya105]

Yes I am sorry for that ......only the problem seemed so similar to mine that i posted it here...