إخفاء النصوص في الصور (ستيغانوغرافيا).

Hidden, not encrypted: encrypt sensitive text first. JPEG compression, resizing and social-media uploads destroy the message. Images up to 40 MB. Everything is calculated in your browser; nothing you type is uploaded.

Each bit of the message (with a small header) replaces the lowest bit of a red, green or blue value, changing colours by at most 1 out of 255.

A 30-character message hidden in a photo leaves it looking identical; reading the downloaded PNG gives the message back.