Method for Synchronizing the Playback of an Audio File with an Associated Video File

A method for synchronizing the playback of an audio file with an associated video file in a computer network comprising:

• an audio client player configured to playback the audio file,
• a video client player configured to playback the video file, and
• a server hosting a web application, the server comprising a data store;
• wherein the method comprises:
• periodically sending, by the video client player, a video playback position (VP) of the video file to the web application,
• storing, by the web application, the video playback position (VP) of the video file and a timestamp at reception (RTS) of the video playback position (VP) in the data store, requesting, by the audio client player, a video playback position (VP) to the web application,
• receiving, by the audio client player, the last stored video playback position (VP), the timestamp at reception (RTS) of the last stored video playback position (VP), and the current server timestamp (CTS) from the web application, and
• computing, by the audio client player, an audio playback position (AP) with the last stored video playback position (VP), the timestamp at reception (RTS) of the last stored video playback position (VP), and the current server timestamp (CTS);
• wherein the audio playback position is computed according to:
• audio playback position (AP)=last stored video playback position (VP)+k·(current server timestamp (CTS)−timestamp at reception (RTS) of the last stored video playback position (VP)), with k≥0.

A server in a system for synchronizing the playback of an audio file with an associated video file, the server being in a computer network comprising an audio client player configured to playback the audio file, and a video client player configured to playback the video file;

• wherein the server is arranged to host a web application and wherein the server comprises a data store;
• wherein the web application is arranged to:
• periodically receive, from the video client player, a video playback position (VP) of the video file,
• store the video playback position (VP) of the video file and a timestamp at reception (RTS) of the video playback position (VP) in the data store,
• receive a request from the audio client player for a video playback position (VP),
• send to the audio client player the last stored video playback position (VP), the timestamp at reception (RTS) of the last stored video playback position (VP), and the current server timestamp (CTS),
• wherein the last stored video playback position (VP), the timestamp at reception (RTS) of the last stored video playback position (VP), and the current server timestamp (CTS) enable the audio client player to compute the audio playback position according to:
• audio playback position (AP)=last stored video playback position (VP)+k·(current server timestamp (CTS)−timestamp at reception (RTS) of the last stored video playback position (VP)), with k≥0.

A method of determining an audio playback position for an audio device to set the reproduction of an audio file in the audio device such that output audio of the audio device is synchronized with video being reproduced in a separate video device,

• wherein the method comprises:
• periodically storing a video playback position (VP) and a timestamp at reception (RTS) of the video playback position (VP),
• after receipt of a request from the audio device, determining the audio playback position for the audio device by calculating:
• audio playback position (AP)=last stored video playback position (VP)+(current server timestamp (CTS)−timestamp at reception (RTS) of the last stored video playback position (VP)).

An audio client player in a system for synchronizing the playback of an audio file with an associated video file, the audio client player being configured to playback the audio file, and being in a computer network comprising a server, and a video client player configured to playback the video file;

• wherein audio client player is arranged to:
• send a request to the server for a video playback position (VP),
• receive from the server a last stored video playback position (VP) received from the video client player (100), the timestamp at reception (RTS) of the last stored video playback position (VP), and the current server timestamp (CTS),
• wherein the last stored video playback position (VP), the timestamp at reception (RTS) of the last stored video playback position (VP), and the current server timestamp (CTS) enable the audio client player (200) to compute the audio playback position according to:
• audio playback position (AP)=last stored video playback position (VP)+k·(current server timestamp (CTS)−timestamp at reception (RTS) of the last stored video playback position (VP)), with k≥0.