Content reproduction program and content reproduction device

A computer-readable non-transitory recording medium comprising a content reproduction program for causing a computer to implement:

• a sound detection unit that detects sound of first content reproduced outside the computer by using a microphone, the sound being watermark data embedded in the first content;
• a time axis determination unit that determines, on the basis of the detected sound, a time axis of second content reproduced subsequent to the first content outside the computer by associating reproduction timing of the second content with time;
• and
• a content reproduction unit that reproduces third content corresponding to the second content in synchronization with reproduction of the second content on the basis of the determined time axis,
• wherein the watermark data contains first data for determining the time axis,
• wherein the sound detection unit further detects a feature amount of sound of the second content reproduced outside the computer, and
• wherein the time axis determination unit further determines the time axis of the second content by comparing the feature amount of the sound of the second content with reference data, the reference data being data in which the feature amount is associated with the reproduction timing of the second content.