How can I Stretch an image in a LibreOffice Impress presentation to fill the page?

Question

After adding an image in a LibreOffice Impress presentation, you can manually move it around and scale it (either proportionally or each dimension independently).

Is it possible to automatically make an image fill the entire page, preferably keeping its proportions and centering the image? I mean to have a page-filling background image.

So if the page and image aspect ratios are not the same, a left and right column or top and bottom row of the image will fall outside the page, but the page is fully covered.

Answer 1

1. Right click on the page and choose Page Setup.... Note the width and height of the Paper Format, then close the window.
2. Right click the image and choose Position and Size...
3. Under Size, choose the center Base Point and check Keep Ratio
4. If the image is taller than the Paper Format, set the image width to match the Paper Format width.
5. If the image is wider than the Paper Format, set the image height to match the Paper Format height.
6. Right click on the image and choose Alignment/Center
7. Right click on the image and choose Alignment/Centered

Answer 2

Usually to get an image to scale proportionally you simply need to hold down the [shift] key while dragging it larger.

Simply do this and drag it as big as it will go.

Answer 3

Make sure you're in 'Normal' view mode (not notes).

1. Right click -> "Set background image"
2. Paste image, or use file manager to select the image
3. Background setting for all pages? ("NO" if you just want it on the current page)

Unfortunately this process does not actually maintain aspect ratio. It may be good enough depending on the shape and content of your original. If not, you'll have to paste the image into the slide itself (not background); then Ctrl+click+drag a corner handle to make it "fit". Then right-click->cut THAT and Paste in step 2 above.

Answer 4

The accepted answer nails this one and is exactly how I do precise positioning on a single or couple images.
However I had several dozen to do and wanted as little interaction with pointing and clicking in that dialog as possible. My solution was to customize the keyboard to add alignment shortcuts (in my case I wanted Top and Centered) then used the side panel to set the size. Select image, two keyboard shortcuts, and type one number. For me it eliminated the most frustrating part of the Size/Position dialog which was selecting the anchor points.