It is not accurate to say that an AI algorithm can upscale a 1080p video to 4K resolution by capturing footage of a 4K TV screen using a 4K camera. While it is true that some TVs and other devices are capable of upscaling lower resolution content to fit the higher resolution of a 4K screen, this process does not actually create new information or details that were not present in the original source. Instead, it relies on interpolation and other techniques to fill in the gaps and create a more seamless, higher resolution image.
When it comes to upscaling video content, there are several factors that can affect the quality of the final result. One of the most important is the quality of the original source material. If the original 1080p video is of poor quality or has a lot of compression artifacts, it will be much more difficult to produce a high-quality 4K output. Additionally, the capabilities of the upscaling algorithm and the device being used to perform the upscaling can also play a role in determining the final result. In general, it is not possible to simply capture footage of a 4K TV screen using a 4K camera and produce a 4K version of a 1080p video with the same level of detail and quality as the original source.