If you want to spruce up your family's archival photos, Remini is a good option. This AI-based service is designed to convert low-resolution photos and videos into high-resolution images. It has options for face smoothing, color balancing, noise reduction and background detail restoration, making it good for improving old, yellowed or otherwise degraded photos. Remini is available as a simple API and works on phones, so it's easy to use and incorporate into other apps.
Another good option is Nostalgia Photos. This service is geared more toward removing artifacts and other problems that plagued photos in the past while preserving the original details. It employs a modern algorithm to produce natural-looking, high-resolution results. Each photo can be restored with up to three different options, and the service protects privacy by deleting processed photos from its servers after 24 hours.
If you want a suite of photo restoration and enhancement tools, check out ImageColorizer. This cloud-based service uses machine learning technology to restore and enhance old photos. It can colorize black and white photos, upscale faces and details, remove blur and remove scratches. With a free plan and several paid options, it's available for a range of needs and budgets.
Last, Let's Enhance offers AI-based image enhancement and generation. It can upscale and enhance photos to 4K and higher resolution, remove backgrounds and apply HDR filters. It's geared for creative professionals, eCommerce and real estate, but you can try it for free and pay with credit-based pricing models.