Allow different PDF image compressions

[ronnyb]

So I recently finished a 48 pg children's book with full page illustrations spanning every spread. Some strange discrepancies in file sizes I wanted to ask for clarity on:

 

1. The original illustrations placed were UNCOMPRESSED RGB TIFFs @ 300 dpi. Size of the folder containing the TIFFs = 817 MB. Exported PDFs without JPG compression. Size of the folder containing all exported PDFs = 820 MB.

2. I saved all TIFFs with ZIP compression @ 300 dpi. Size of folder containing compressed TIFFs = 487 MB. Exported PDFs without JPG compression. Size of folder containing all exported PDFs = 802 MB.

 

This was a YUGE surprise. What's going on? I had to compress with JPG which I wanted to avoid in order to get PixartPrinting.com to accept the files. I don't want to print JPGs.

[MikeW]

Images are decompressed when placed/embedded. Compression really only exists on disk and for some application, with original or proxy images in RAM. Because you are using tiffs, when creating the PDFs you are using a first-generation compression when making the PDFs. Unlike some software, Serif's Affinity line don't allow one to choose the compression types and levels for the main 3 types of images. It's JPEG or nothing on all image types. But like I wrote, it should make a difference in quality for anything short of a high-end coffee table book printed traditionally via offset printing at a high LPI.

 

It would be nice, and it will likely be necessary, for APub to offer compression types and levels for the 3 image types. And if so, I would imagine it would end up in AD as well.

 

Mike