Copyright Registration
Copyright exists as soon as an image is created and this copyright belongs to the author, either the photographer or the designer of the image.
The copyright owner can enforce their rights against anyone infringing their copyright but they are often unable to claim statutory damages in jurisdictions that allow such damages to be claimed unless they have previously registered the image with the Copyright Office.
For instance in the US the Act allows for damages to be awarded for copyright infringement for images that have been registered of between $750 and $150,000 plus costs and attorney fees for each infringement depending on the circumstances whilst the copyright registration of an image is prima facie evidence of the ownership of the copyright.