Video playback buffer control

A device for controlling a video playback buffer, the device comprising:

• a memory;
• and
• a processor coupled to the memory, wherein the device is configured to:
• determine a buffer status metric specifying a current number of video packets in a video playback buffer in a user device or a current amount of video data in the video playback buffer;
• trigger a buffer status action based on said buffer status metric that specifies the current amount of video packets in said video playback buffer or the current amount of video data in the video playback buffer and further based on at least a mobility metric representing a mobility pattern of said user device or a radio quality metric representing a signal strength of a radio channel carrying video packets towards said user device;
• and
• perform the triggered buffer status action, wherein the device is configured to perform the triggered buffer status action by performing a process that includes at least one of the following steps:
• during a given period of time, adding at least X video packets to the video playback buffer while not removing any video packets from the video playback buffer, thereby increasing the number of video packets in the playback buffer by at least X, where X is an integer;
• triggering a handover from a current radio access network to which the user device is currently connected to another radio access network;
• increasing a maximum size of the video playback buffer;
• or
• reducing a playback bitrate of video data from the video playback buffer.

A method of controlling a video playback buffer in a user device, said method comprising:

• determining a buffer status metric specifying a current amount of video packets in said video playback buffer;
• and
• triggering a buffer status action based on said buffer status metric that specifies the current number of video packets in said video playback buffer and based on information indicating a number of handovers experienced by the user device within a measurement time window, wherein
• the information indicating a number of handovers experienced by the user device within a measurement time window comprises at least one:
• of i) a number of vertical handovers between radio access networks of different radio access technologies, ii) a number of horizontal handovers between radio access points of a same radio access technology, or iii) a number of changes in position of the user device.

A method of controlling a video playback buffer in a user device, said method comprising:

• determining a buffer status metric specifying a current amount of video packets in said video playback buffer;
• and
• triggering a buffer status action based on said buffer status metric that specifies the current number of video packets in said video playback buffer and based on information indicating a number of handovers experienced by the user device within a measurement time window, wherein
• wherein a handover comprises at least one of:
• i) a change in cellular identifier without a change in cellular IP address or a change in the cellular network type;
• ii) a change in WiFi access point name without a change in WiFi IP address;
• iii) a change in a cellular network type but no change in cellular IP address;
• or iv) a change between a cellular IP address and a WiFi IP address, and a change in network type.

A method of controlling a video playback buffer in a user device, the method comprising:

• determining a buffer status metric specifying a current amount of video packets in the video playback buffer;
• inputting into a buffer control model the buffer status metric together with a mobility metric and/or a radio quality metric, wherein the mobility metric represents a mobility pattern of the user device and the radio quality metric represents a signal strength of a radio channel carrying video packets towards the user device;
• as a result of inputting into the buffer control model the buffer status metric together with the mobility metric and/or the radio quality metric, receiving from the buffer control model candidate information indicating a set of M buffer status actions, wherein the set of M buffer status actions is selected by the buffer control model from a set of N available buffer status actions, where N>M and M>1, wherein the candidate information includes first candidate information indicating a first buffer status action and second candidate information indicating a second buffer status action, and each of the buffer status actions included in the set is predicted by the buffer control model to achieve a defined video playback buffer status result;
• selecting a buffer status action from the candidate set of buffer status actions;
• and
• performing the selected buffer status action.