Don’t fancy digiKam’s default splash screen? No problem, you can easily replace it with your own photo. First off, you need to prepare a photo for the splash screen. To do this, use an image editing application like GIMP to resize the photo you want to 500×307 pixels. Save the resized image in the PNG format. Next, grab the splash-digikam.svgz file from digiKam’s source code repository and open the downloaded file in the Inkscape vector graphics editor. Remove the existing background image and use the File | Import command to insert the image you’ve just created. Position it correctly and lower it to the bottom using the End key (or the Object | Lower to Bottom command). Use then the File | Export Bitmap command to save the created splash screen as splash-digikam.png. Next, you have to find the exact location of the splash-digikam.png file. On Linux, you can do this by running the find / -name splash-digikam.png command in the terminal. Alternatively, you can use the searching capabilities of your preferred file manager. Once you’ve located the file, replace it with your own splash screen, launch digiKam, and behold your masterpiece.
For your convenience, I’ve made a sample splash screen and all the required files available as one neat package. And if you want to share your own splash screen with other digiKam users, you are welcome to post it on the digiKam Users Flickr group.