Caught on camera ... this panda porn movies encounter was apparently unsuccessful.

BANGKOK, Thailand (CNN) -- After Thailand's most popular animal couple failed to mate, zoo officials are gearing up for plan B -- a DVD they hope will get Chuang Chuang and Lin Hui in the mood for love.

The pandas' first mating season -- a three-day window -- came last week. Despite a widely-publicized encounter between Chuang Chuang, a 6-year-old male, and 5-year-old Lin Hui, the mating apparently was unsuccessful.

Zoo administrator Prasertsak Puttrakul, who leads a team taking care of the pandas, noted they tend to live in isolation in the wild, and do not witness other pandas mating. "That's why they are bound to extinction should there be no help," he said.

Recent panda reproduction in the United States and Japan stemmed from artificial breeding, he said.

Because of that, Prasertsak has prepared a DVD of pandas having sexual intercourse to show the couple, hoping the demonstration -- call it panda porn -- will inspire them to make a love connection.

The pandas are on a 10-year loan from China to Thailand's Chieng Mai Zoo, about 700 kilometers (435 miles) north of Bangkok.

They have proved enormously popular -- in the past two years, the number of visitors to the zoo has doubled from 600,000 to 1.2 million people. Of those, three-fourths come to see the panda couple, paying an extra 50 baht ($1.50) on top of the zoo entrance fee.

The Thai government pays $250,000 a year to Wulong Panda Research Institute in China to rent Chuang Chuang -- whose name means "clever" -- and Lin Hui, whose name means "beautiful forest."