The USA international joined the Black Cats for around £7m from AZ Alkmaar last summer, but he only managed one goal in 31 games during his debut campaign in England.
However, the 24-year-old forward is confident that he can make a bigger impact on the team this term.
"Coming to Sunderland as a whole was different, but this is where you have to adapt," he told the Sunderland Echo. "It was a tough year for me last year. I struggled, everybody struggled.
"When things don't go well, you analyse what you can do better. I've done that and hopefully this season I can start out on the right foot."
Altidore is currently back in training after suffering a hamstring injury while playing for the USA at the World Cup.