Freedom was in color. That was the indelible memory that Omar Rodríguez Saludes remembered the day he boarded an Iberia flight to Spain from Havana in 2010. Until then, his world was sketched in drab shades of gray, green and white. Those were the colors of his imprisonment: gray for his rags, white for the walls and green for the guards.

“To see any other color was rare,” Mr. Rodríguez Saludes said. “But in that plane, I saw colors. Everyone was dressed regularly. I saw colors I had not seen in a long time.”

Seven years, to be exact. Journalism was the reason for his imprisonment. Specifically, everyday shots of Havana life, far from the gleaming tourist hotels and beaches. His world showed a crumbling city with haggard faces, presided over, Oz-like, by billboards with revolutionary slogans.

He had been among some 20 independent journalists who were rounded up by the Cuban government during a sweep of 75 dissidents in March 2003, and given lengthy sentences after quick trials. They were said to be traitors and mercenaries in the service of the United States government, even though international human rights and journalists groups defended them as prisoners of conscience.