Hello,
I'm not really able to identify or see the issue via the pictures you uploaded. Hopefully other people within the community can see something i'm not able to identify.
However I wanted to still provide some guidance so you can narrow this down.
Update iOS: If you haven't already. Update to the latest version of iOS that is available for your iPhone model. I always advise this in the event an updated version was released prior or after you posted for help. The latest version should be: 13.3
Test Camera: Make sure you test the front & back camera for photos. See if the issue persists. I also advise recording a video with the front & back camera to see if any issues occur when reviewing your video. If you haven't done so already, i'd also test other camera apps to see if the issue is isolated to the app you're using. This better narrows down the issue to camera specific and app specific behavior vs. system wide.
Document your results and I would contact Apple Support and have them run a hardware diagnostic test. I believe this also scans for camera hardware issues. They can also of course escalate this to Engineering with the photo samples / video samples to see if any other reports have come in with this behavior and they of course will give a final call if this is hardware issue or not. That way you're only having to service the iPhone as a last resort.