mORMot Open Source

ab

Administrator

From: France

Registered: 2010-06-21

Posts: 14,659

Website

Highly reduced generated PDF file size

We have reduced PDF generated file size for all version of the PDF format, by trimming any uneeded space in the generated content.
See http://synopse.info/fossil/info/a6622c2901

We introduced a new optional PDFGeneratePDF15File property for even better compression, using advanced features (Object Streams and Cross-Reference Streams) of the PDF 1.5 format.
This PDF 1.5 format needs Acrobot 6.0 and up to open them. Which should be the case on your computer.
Can be up to 70% smaller for a pdf with a lot of pages with simple context.

I suspect our library is able to generate the smallest file size possible, even in respect for other alternative libraries.

We still have an issue which disallow to enable the full benefit of PDFGeneratePDF15File=true when encryption is set.
But even if the files may be a bit bigger, the generated content is still perfectly valid.
If you have an idea about the problem cause, your feedback is welcome!

See http://blog.synopse.info/post/2013/06/2 … -file-size

blewis

Member

Registered: 2010-11-18

Posts: 3

Re: Highly reduced generated PDF file size

I did a comparison of file size between 1.17 and 1.18. On a 20 page file, generated from HTML (htmlviewer):

1.17: 365KB
1.18 pdf15=false: 498KB
1.18 pdf=true:   : 497KB

Using acrobat, I can reduce the file sie to 131KB.

Are there some settings I have missed?

ab

Administrator

From: France

Registered: 2010-06-21

Posts: 14,659

Website

Re: Highly reduced generated PDF file size

This is not with the same options or content.

blewis

Member

Registered: 2010-11-18

Posts: 3

Re: Highly reduced generated PDF file size

Yes, same content and settings.

The content does have images, but they are the same images.

I adjusted the image compression settings but it did not alter the difference between 1.17 and 1.18.