Acrobat deleting images during optimization

[vitro_DHG]

Hi All,

I am optimizing a PDF with Acrobat .. and it is deleting images on 3 pages .. images I need.

I've tried to insure they are on the top layer .. but they are there in the uncompressed version .. gone in the compressed version.

Any ideas?

Thanks, David

[Dov Isaacs]

It would help tremendously if you provided more information such as Acrobat version, OS, and all the optimization settings you are using. Furthermore without posting a sample file (with before and after versions), it is virtually impossible for any of us to assist you here.

          - Dov

[vitro_DHG]

Thanks Dov,

Before: Dropbox - •• 2018-10-09 Vitro Innostars Chinese SEMIFINAL.pdf

After: Dropbox - ••• 2018-10-09 Vitro Innostars Chinese SEMIFINAL.pdf

Acrobat Pro DC 2019.008.20074

Macbook Pro - High Sierra 10.13.6

[Dov Isaacs]

OK, got the files, thank you.

However, you did not send me the settings you used for optimization.

Regardless, on my system running the latest copy of Acrobat Pro DC with all updates, I see no visual difference between the files. In comparing the files, I don't see any images missing. On exactly what pages do you think images are missing? All the images of the larger file appear in the smaller file. The only significant difference I see between the files is that in the optimized file, images are downsampled to 150 dpi (as opposed to 300 dpi in the original file).

     - Dov

[vitro_DHG]

Hi Dov,

Images are missing on Pages 4, 5 and 11.

On pages 4 and 5 the Microchip logo is missing.

On page 11 the 3 patent filing images are missing.

I used standard settings for Mobile compression.

Thanks

[Dov Isaacs · Accepted solution]

You are probably not going to believe this, but all the images you are missing on the optimized version show up when I view the optimized version on three separate systems. The problem isn't the resultant PDF file. Something else is going on. And FWIW, not only do they show up on Acrobat DC Pro on my Windows system, but also on the Adobe Acrobat Reader for iOS.

Something is wrong with your configuration, possibly a video driver or maybe even Acrobat preferences. If you have the Use 2D graphics acceleration option enabled under Preferences=>Page Display, try disabling it and see if that makes a difference.

          - Dov

[Dov Isaacs]

Have you tried my suggestions yet? Would like to confirm what is going on.

Thanks.

          - Dov

[morpholux]

Hi. I got the same problem. But I confirm that it is something that has to do with graphic card used by some apps, even from Acrobat or mac OS Viewer. If you drop the PDF file where images are not showing in a browser like Chrome, the missing images are suddenly revealed.

[Ari353619529sr7]

I have the same issue as well.

Images from Compressed PDFs show up in Acrobat Reader, but appear missing in the OS X Preview application, OS X v14.2.1.

Seems the compressed PDFs work fine in Acrobat products, but images are not supported in compressed PDFs made with Acrobat in other readers, which is a big problem for distributing digitally 

[Peter Villevoye]

Same here, since this week ! Also, on a Mac.

Used Optimizing before on numerous files – no problem. But now they simply don't appear.

Images do show up in Acrobat and in Chrome, but not in Preview or Safari (probably due to their common engine). De- and re-installed Acrobat, but no improvement.

Then I thought: I created the original file with Google Docs. How about a plain vanilla PDF from InDesign ? And this turns out to retain its images after optimization ! So there might a some conflict with Google's compression scheme, not correctly being decoded and encoded again for Mac OS by Acrobat ?

[Peter Villevoye]

I tested some more, using Save as Smaller File and Save Optimized with an optimisation setting without the options for imagery checked. But the images are still disappearing and not re-appearing in Preview. (Mac OS 12.6.2, Acrobat 23.8.20533.0). 

As a temporary work-around, I converted the PDF into a PDFa, and this at least brings the file size down quite a lot and still shows up correctly in Preview.

For anyone interested, I enclosed some files to test and tweak.

Note: the "original" PDF was too large to send. So I deleted the majority of pages with Preview. Nevertheless, the larger original and this smaller one misbehave in exactly the same way.

The larger PDF has the following Document Properties, revealing Skia/PDF m123 Google Docs Renderer as the PDF Producer: 

 

[Peter Villevoye]

Well, my specific problem has vanished...

Having time to re-visit this problem and the offered insights, I tried to reproduce the erratic workflow, but it seems that it must have been some strange glitch. Images in newly created PDFs show up correctly now in the earlier mentioned misbehaving PDF viewers. I also noticed that the PDF producer version of Google Docs went up two notches, so maybe that killed the bug ?

Edit: I also tested to re-optimize the older files, and they still missed the images in certain viewers. So there probably has been a bug at the initial creation of those PDFs...

[justinbb]

This problem can be solved by setting the PDF compatibility version to 5.0 or below at the beginning of the save-with-reduced-size process. Saving as PDF/A has a similar effect, as it sets the compatibility version very low.

The Mac built-in PDF engine has various incompatibilities, especially with more recent PDF versions (no idea why Apple can't stay up to date with the standard).

[justinbb]

In particular: an optimized PDF with Acrobat 6 (PDF 1.5) compatibility may use the JPXDecode filter, which is how PDF specifies JPEG-2000 compression. Other parts of the Apple system software can handle JPEG-2000, but the support for the format in PDF isn't there. So these images are omitted when the PDF is displayed in Mac Preview.

[Peter Villevoye]

Thanks for the tip ! But the problematic files were both produced and optimized in the super-compatible version 1.4, so this should rule out any higher intelligence in content formats and codecs.