ZLIB library in PDF engine of Illustrator 2024

[MICHAEL36018258rd0l]

Dear Adobe-Community,

we have noticed that the PDFs created in Illustrator 2022 differ from those created in Illustrator 2024. The difference seems to lie in the use of the ZLIB library. Our subsequent applications now have difficulties processing the PDF files. It usually fails when decompressing the PDF data: "inflate failed, ZLIB error -5: (null)". We suspect that Illustrator 2024 uses a newer PDF engine that uses a newer version of the ZLIB library. Is there any further information on this?

Many thanks in advance.
Best regards
Michael

[Anubhav M]

Hello @MICHAEL36018258rd0l,

Thanks for reaching out. I have checked this with the team, and they confirmed that there have been no major changes to Flate/ZLIB. Would you mind sharing more details about the PDF library you are using so I can check it with them?

Thanks,
Anubhav

[MICHAEL36018258rd0l]

Hi Anubhav,

we're using the "pdfresolve"-library from HELIOS to manipulate the PDF files afterwards.

Also I can provide PDFs which work and same PDF which doesn't work.

I even compared the PDF files on low-level, but i didn't find any problems within.

The only way I can explain it is that compression is the cause.

Michael

[Anshul_Saini]

Hi @MICHAEL36018258rd0l,

Thank you for the detailed explanation. I understand how frustrating this issue can be.

Could you please provide a sample PDF file that works and one that doesn’t? It would be helpful to know the exact versions of Illustrator 2022 and Illustrator 2024 you are using, along with a screenshot of the error message you’re encountering.

Also, has there been any update or change from HELIOS since Illustrator 2022? It might be worth checking if there have been any modifications on their end that could be affecting the PDF handling.

Looking forward to your response!

Best regards,
Anshul Saini

[MICHAEL36018258rd0l]

Hi Anshul,

can I send the files to you directly? I don't want them to be publish here in the public community.

Michael

[Anubhav M]

Hello @MICHAEL36018258rd0l,

Kindly share a public link to a sample file after uploading it to Dropbox/Google Drive/etc., the exact version of Illustrator 2022/2024 installed, and screenshots / a screen recording of the problem (https://adobe.ly/3Ak2MLk), via DM to Anshul or me, so we can investigate this further.

Looking forward to hearing from you.

Thanks,

Anubhav