npub1u27r9h3j9pvrplaffsmpn698e8xhmuqhdgcxldv67ammql9pumnqha3qfq (npub1u27…3qfq) I think the short answer is "hashing". See, e.g.:
https://www.missingkids.org/ourwork/ncmecdata
https://www.thorn.org/reporting-child-sexual-abuse-content-shared-hash/
https://www.thorn.org/blog/hashing-detect-child-sex-abuse-imagery/
https://safety.google/stories/hash-matching-to-help-ncmec/
William Pietri
npub13u…rndnc
2023-08-04 22:12:35 UTC
in reply to nevent1q…wcyn
Author Public Key
npub13upkkmn8znwh048kvsl9cmhd3ucjk5wl0246xy5hmxp5wjlp5a4swrndncSeen on
wss://nos.lolPublished at
2023-08-04 22:12:35 UTCEvent JSON
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