SEOUL, South Korea — Soon after the ferry began to tilt, there was nervous laughter, jokes about the Titanic and talk of selfies and Facebook posts from the doomed high school students huddled below deck.But the lighthearted atmosphere soon turned serious as the listing worsened. Fear began building, and one student asked, “Am I really going to die?”The shaky video — at times poignant and heartbreaking as the teens said last words to their loved ones — was found on the cellphone belonging to 17-year-old Park Su-hyeon when his body was recovered after the disaster on the morning of April 16 off South Korea.The boy’s father, Park Jong-dae, provided it Thursday to The Associated Press, saying he wanted to show the world the conditions aboard the Sewol as it sank. He earlier released it to select South Korean media.More than 300 people are dead or missing in the disaster, which has plunged South Korea into mourning and touched off anger and shame. About 220 bodies, mostly from inside the submerged vessel, have been recovered. More than 80 percent of the victims were students from a high school in Ansan, south of Seoul, on their way to the tourist island of Jeju for a school trip.