system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:How does a mirror of a video make it harder to takedown?

On places like putlocker and other streaming sites they have mirrors of videos where the video is reflected horizontally. How does that make it harder for copyright infringement?
gpt
These horizontally mirrored videos that you speak of are effective at evading many automatic detection systems that are designed to fingerprint copyright source material and automatically detect similar (potentially infringing) content that is posted to the site.

When the (audio) pitch is altered slightly and/or the video is mirrored horizontally, the 'fingerprint' of the original source material is no longer sufficient to identify the altered mirror video that is posted, thus these videos can remain on the site longer and evade detection until they are manually reported or discovered by one of the site's operators or content moderators.