People appearance with pics/vids always change for me.

Hello, this is my first post here.
I really require help as this obsession has caused me a lot of stress which eventually made me feel down and even depressed at times.

My problem: I sometimes look at people's pictures or videos and for some reason my mind can't make out on what they really would look like.
For example, someone sends me a picture and i look at it and its fine, but then they send another picture and i think "They look different" and i start to stress over it.
I begin to put both pictures next to eachother and compare them, to see what is exactly different and why.

I have it with videos too, if someone sends me a video of themselves like certain activities or a video of them talking about something, i always compare all the videos i have of them like i do with pictures.
I compare it, looking on what is different and why its different.

Sometimes i even put pictures next to the video to see if they look like those pictures, but sometimes i cant make out which picture is more closer to the video.
I would put picture 1 on video 1, then picture 2 on video 1, and then picture 1 on video 2... to see which is easier to compare to eachother.

I can see resemblenses but sometimes my mind just can't find peace with this.
For some reason i cant visualize people in my mind, they always look different from the video or pictures which increases my fear(?) or paranoia(?) not sure which it is.

I've had this for 10 years and have been struggling with it heavily.
I am out of options, i have no idea what to do, i am stressed out at the moment and desperate.

Thanks.

This is a very unusual obsession, but certainly could be OCD. I'd encourage you to research and visit a reputable therapist in your area and see if you can get an official diagnosis for whatever might be going on if you haven't already.