The earliest example of that general technology would probably be the Leica camera, as this was the first time a negative had been designed for enlargement rath

The earliest example of that general technology would probably be the Leica camera, as this was the first time a negative had been designed for enlargement rather than contact printing (or at least, for high degrees of enlargement). This is only really physically reducing the size of the storage device though, not really compression. https://gmpphoto.blogspot.com/2018/04/ur-leica-most-influential-photographic.html https://gmpphoto.blogspot.com/2018/04/ur-leica-most-influent... In terms of compression as a whole, the first example would probably be military/commercial codebooks. A relatively modern example would be the q-code, where a predetermined sequence of words are encoded as a 3-letter sequence ("QRA" becomes "What is the name of your vessel/station") but I'm sure there are prior examples. https://en.wikipedia.org/wiki/Q_code https://en.wikipedia.org/wiki/Q_code