How Does Impress Save Images?

[Ninpodeshi]

I just created a collection of music symbol vector images (about 200 total). I’m in the process of donating these to a public domain vector website to make them available for others to use too. (I’m considering packaging the basic images into a gallery for LO.)

The site admin and I also want a way for people to download all the images in the collection at once. I inserted all the images into an Impress file so I can access them more easily, and offered to give the admin that file to offer on his site. I was about to send them when I noticed a problem. The actual vector images are 121 Mb in total size, but the Impress doc is only 92 Mb. Why is there a loss of size? Are some of the images being saved as non-svg images? Do I need to change what I’m doing?

I copied the images from Widows file explorer and pasted into Impress. Using Win10 & LO 7.1

(Sample of a slide of the music vectors above.)

[mikekaganski]

SVGs are plain-text (XML) files. When you put them to an ODG, they are packed into a ZIP. Try to open the ODG as ZIP, and check if SVGs there have the size that you expect.

[Ninpodeshi]

Thank you Mike!

When I open the archive, there is a pictures file that shows 94 Mb packed with 129 Mb total size. Inside that folder there are also .png’s, which is probably why the size appears bigger when looking at the archive? Either way, at least I know that the files are intact.

I really appreciate your help.

[Ninpodeshi]

I don’t see an option to mark your comment as the answer?

[mikekaganski]

That’s because it was a comment. I’m reposting it as an answer, to allow closing it as answered.

[mikekaganski]

The SVGs (XML files) stored in ODG are compressed using ZIP compression. That results in a smaller overall size. The SVGs should be unmodified inside the ODG package.

One may inspect those, if one opens the ODG as a ZIP (which it in fact is), and inspects its contents.