An image enhancement sequence was a feature devised by Chief Miles O'Brien and Neela for Deep Space 9's Cardassian viewscreen. It was used to clarify a distorted image on a photograph.
In 2369, the Bajoran Archives provided Deep Space 9 with the only photograph known to exist of Aamin Marritza at the Gallitep labor camp on Bajor from 2357. Jadzia Dax utilized the image enhancement sequence on a distorted Cardassian and upon viewing the photograph, Kira Nerys found that Marritza bore no resemblance to the Cardassian claiming to be him who was locked away in a holding cell on the station. Dax performed another enhancement sequence on a second Cardassian in the photo at Benjamin Sisko's request and it was shown that Marritza had a striking resemblance to Gul Darhe'el - the butcher at Gallitep. (DS9: "Duet")
In 2373, Captain Sisko used the image enhancement sequence on a wall monitor in his office to examine symbols on a spire seen in a painting of the lost Bajoran city of B'hala. (DS9: "Rapture")