Not digitally embedded as EXIF since it was uploaded to Imgur which AFAIK strip those out, but more like lens scratches and sensor noise, similar to [0]. [0]:

Not digitally embedded as EXIF since it was uploaded to Imgur which AFAIK strip those out, but more like lens scratches and sensor noise, similar to [0]. [0]: https://ieeexplore.ieee.org/document/1634362 https://ieeexplore.ieee.org/document/1634362