Video-based measurement of round-trip latency from user input event to corresponding video output

A method comprising:

• detecting an input event in a client device;
• storing in a memory of the client device a local time associated with the input event;
• transmitting information characterizing the input event from the client device to a remote system over a network;
• and
• receiving in the client device from the remote system a video signal comprising an event index of the input event;
• wherein the event index is extracted from the video signal;
• wherein a round-trip latency between the input event and a corresponding video output of the client device is computed based at least in part on a local time associated with the extracted event index and the stored local time associated with the input event;
• and
• wherein the detecting, storing, transmitting and receiving are performed by at least one processor of the client device.

An apparatus comprising:

• a remote system configured to communicate with a client device over a network;
• the remote system comprising one or more processing devices each comprising a processor coupled to a memory;
• wherein the remote system is further configured:
• to receive from the client device over the network information characterizing an input event detected in the client device and for which the client device stores in a memory thereof a local time associated with the input event;
• to generate an event index based at least in part on the received information;
• to insert the event index into a video signal;
• and
• to transmit the video signal comprising the inserted event index to the client device over the network;
• wherein the event index when extracted from the video signal is utilized to compute a round-trip latency between the input event and a corresponding video output of the client device based at least in part on a local time associated with the extracted event index and the stored local time associated with the input event.

A method comprising:

• receiving in a remote system from a client device over a network information characterizing an input event detected in the client device and for which the client device stores a local time associated with the input event;
• generating an event index based at least in part on the received information;
• inserting the event index into a video signal;
• and
• transmitting the video signal comprising the inserted event index to the client device over the network;
• wherein the event index when extracted from the video signal is utilized to compute a round-trip latency between the input event and a corresponding video output of the client device based at least in part on a local time associated with the extracted event index and the stored local time associated with the input event;
• and
• wherein the receiving, generating, inserting and transmitting are performed by at least one processor of the remote system.