Set local image as a splash screen

Question

How to set a local image as splash screen for Ubuntu 18.04?

Every resource I find is about how to set one of the Plymouth themes as a splash screen but none of them explains how to set a local image as a splash screen.

Answer 1

• Download some image with appropriate resolution (I've downloaded this one)

• Copy it into appropriate place: sudo cp ~/Pictures/wallpapers/forest-wallpapers-1366x768-0000.jpg /boot/grub/nsplash.jpg

• Run sudo update-grub

• Reboot

The next could be helpful if previous method did not work:

• Edit /etc/default/grub file and put there the next:

  GRUB_BACKGROUND="/boot/grub/nsplash.jpg"
  

  You could specify a different path to image.

• Run sudo update-grub

• Reboot

Choosing a GRUB 2 Background Image
GRUB 2 can use PNG, JPG/JPEG and TGA images for the background. The image must meet the following specifications:

JPG/JPEG images must be 8-bit (256 color). Else you will get errors saying "Too many Huffman tables". Since most of the time you will not want to limit yourself to 256 colors (which is totally yesteryear) you will probably find PNG much preferable.
Images should be non-indexed, RGB.
The GIMP image editor is one application which can edit images to conform to the GRUB 2 standards. Use the Image > Mode menu options to set the properties to RGB and ensure the mode is not set to Indexed.

Sample GRUB 2 splash images are contained in the grub2-splashimages package in the Universe repository. The package can be installed in several ways:

Synaptic (if installed). Select and install grub2-splashimages.

Ubuntu Software Center. Search for grub2-splashimages and click the Install button.

Terminal:

sudo apt-get install grub2-splashimages

Once installed, the images are located in the /usr/share/images/grub folder.

In my case I was observing this picture as a splash image in grub menu, however, it does not meet all those specifications:

It could mean those specifications have been written for older grub versions.

Reference