How to detect if video had been sized up (Scaled up) in resolution? On Internet, I can see many videos/movies claim to have FHD (1920x1080) resolution, but on watching they seem to be shot in lower resolution and resized/scaled up using encoder or transcoding tool to 1080p resolution.
My question: is there any tool to detect such scaling up?
If possible, I prefer ffmpeg tool, or knowledge base of such detection.
Thanks,
May i rephrase your question as

How natural does an image look?

If so, you are finding Naturalness Image Quality Evaluator (NIQE). Plz take a look of Naturalness Image Quality Evaluator (NIQE) no-reference image quality score. Then you may find some information from Laboratory for Image &amp; Video Engineering and then you will get some tools like

scikit-video
Video Quality Indicators

Good Luck!