Mysterious Invisible Images

I posted this in another forum and am moving it here

Some/many pdf ebooks are created with tiff images, which the eDGe cannot read. I would like to see support for this.

Originally Posted by NiaTrue

Really? I thought that when PDFs are created, TIFFs get flattened fom vector files--and that assumes they're being exported from something like Quark or InDesign. Not all DPFs are created that way.

Well, I think you're likely right. My head started going where it went because I was playing with some pdf files that the images (tifs) were not rendering in. I rebuilt a few pages changing the image files to jpg, and the problem was gone. So I made an assumption without going further. Your question got me to do some more tests, and indeed, every tif I used worked fine, and I even did some with jpg and zip compressions, and the edge rendered them all. So now I'm really curious as to what is going on. I looked at the metadata in a couple of the books that the images didn't work in, and that was no help either. One PDF was authored in Acrobat 7 and another generated from Ghostscript, so I really have to wonder what is going on.

Pllease, send your PDF to techsupport. I have the same problem (images in PDF not displayed), but I can't send my PDF due very strict "non disclosure agreement"

I have found several pdf with images that don't work. Google pdfs don't show the images, but do show the text. In Internet Archive, none of the ones that look like blank rectangles or say something about metafiles seem to show up at all. Others are kind of random, I check each file to see if it works.

enTourage is working with Adobe to fix the Google problem, and perhaps it will help other pdfs, too.

I've been looking into this some more. I have taken 3 books:

1) the one Rakista put up (http://www.archive.org/details/originsoftotalit00aren) which is an image scan with hidden text. This one rendered completely blank pages on the EE.

2) one with set text (fonts), images and no hidden text layer. This one rendered the text on the EE but not the images.

3) This one was the most complex. It had set text (fonts) with embedded inline images (ie. math symbols and equations) as well as a hidden text layer and images. The text and imbedded images rendered on the EE but the images did not.

All of these pdf files were PDF v1.6 Acrobat 7.x created by various and different applications — Internet Archive/Luradocument PDF v2.28; PDF Creator v9/AFPL Ghostscript v8.5.3; Acrobat 7/Acrobat 7 Paper Capture.


All of these files were created as PDF v1.6 (Acrobat v7), which according to Adobe is backward compatible to Acrobat and Adobe Reader 5.0.


So, my procedure was this — I opened each book in Acrobat Pro 8 (mac) and reprocessed them through Preflight to create three different versions of each — v6, v5 and v4 — and then moved them to the EE. The results were this.


1) Acrobat v6 yielded exactly the same results for all of the books as the original v7 formats (blank pages, missing images).


2) Acrobat v5 worked for all three. Although with Rakista's book on the EE, I was not able to select just one word of text, it kept selecting the whole line?? This whole book was scanned in color, so the contrast isn't that great, but I can't really see how that could affect text selection??


3) Acrobat v4 worked for Books 2 and 3, but for Book 1, it stripped the hidden text layer.


I also looked at two other files. One that has always rendered correctly on the EE, was created as Acrobat 7.x with Gsview/AFPL Ghostscript v8.5.4. This one has a fairly complex layout — text in various sizes and column widths with images. I think it would have had to have been scanned (with ocr), layered, merged and flattened. There were only two pages with hidden layers (with basically nothing on them) that I think just got missed when the hidden layer was being stripped.


The other was one I created myself, which is an image layer with a hidden text layer, but it has a font extraction/corruption issue happening with it. It works fine in Acrobat but doesn't render on the EE, no matter what I do with it, so I am assuming it is the font issue that is causing the problem with this one.


So, all of this is suggesting that Acrobat v7.x is NOT ALWAYS backward compatible to v5. I seems to have something to do with how the layers are being handled.


At any rate, the workaround seems to be to reprocess them to Acrobat v5.

Originally Posted by borisb

That's some terrific research!

I checked my Adobe Acrobat Standard 8.0, and I couldn't find a way to save an Acrobat v7.x PDF as Acrobat v5.x. Any suggestions?

I'm using Acrobat 8 Pro for mac. I'm not sure what the Standard versions can do, but this was the procedure I followed.

First I did a Save As using a different filename to protect my original file and then,

Under Advanced (in the menu bar) > Preflight > select 'compatible with Acrobat 5' > Execute. (leave the 'run without applying fixups' unchecked)

And I just used the Acrobat default settings. There is another place that you can define custom settings, but I didn't do that.

I'm not sure if the Standard editions have the preflight feature.

Originally Posted by borisb

Ah - the Standard edition doesn't seem to have "Preflight" or a way to set the version when doing a "Save As" (there's a "Settings" button there, but not enabled).

The Save As is just a means to keep your original file intact in case something goes wrong. It doesn't allow you to set the Acrobat version. The only place I could find to do that was through the Preflight feature.

Too bad. I thought the Standard version might have it. I wonder if any of the open source pdf software has a means of changing the version? Some of them are getting fairly robust these days.

Boris,

Does Acrobat standard have a pdf optimizer? Advanced > pdf optimizer

Boy, I hope Adobe updates their eReader software, so all we need to do is open the pdf. The sooner, the better.

Originally Posted by dcubed2

Boy, I hope Adobe updates their eReader software, so all we need to do is open the pdf. The sooner, the better.

Yeah. Or, they need to fix their backward compatability issues. When working in InDesign CS3 and exporting to pdf, this is the Adobe dialogue for exporting (high quality print) to Acrobat 8

Use these settings to create Adobe PDF documents for quality printing on desktop printers and proofers. Created PDF documents can be opened with Acrobat and Adobe Reader 5.0 and later.

Gotta love those Adobe guys

I also tried the PDF Optimizer. Somewhat more cumbersome. I set up a custom setting for the EE so I wouldn't lose the hidden layers, etc. This worked as well. Again, setting the compatibility to Acrobat 5.

And last but not least, I use an Open Source office suite called Neo Office. I opened the pdf (it takes a long time as it opens it in a drawing program) and exported that to a pdf, and, that worked. But, bear in mind, that this was a file without layers. So, I tried Rakista's with the hidden text layer, and it was a bit of a disaster. But, because it worked for the one without layers, some of the open source pdf viewers/editors may well be able to do this, and do it better.

Originally Posted by borisb

aidren - no, it's not there. I checked the Adobe Acrobat Feature Matrix and "preflight" is only listed for Pro and Extended.

I was asking about "PDF Optimizer", actually?

Another bit of info to this ongoing saga. The Adobe Reader software uses a PDF/a file structure. I discovered in Acrobat 8 Pro there is simple means of converting the file .... Comments>Enable for commenting in Adobe Reader... (You have to have a document open to view this) — perhaps someone can check to see if this option is available in Acrobat Standard?

This opens a dialogue warning that some functions will be lost (you lose the ability to create bookmarks/toc) but converts the document to pdf/a requirements. The end result is you can now see the missing images and also any hilites and comment symbols (although they are not interactive on the ereader). If you want to be able to view the contents of a note (made in acrobat) use the "rectangle with text" tool and it will be visible in the ereader.

If you want to to add notes again in acrobat, use the "keyboard shortcut" for creating a bookmark (as this operation is not available in any menus now) and a dialogue appears allowing you to convert back to the fully functional pdf file type.

Thanks for looking, Boris... but that's too bad.