Method and apparatus for streaming media content to client devices

An apparatus for switching a client device between encoded bitrates for a streamed media presentation, the apparatus comprising:

• an interface configured to receive requests from the client device and provide media segments to the client device, wherein each media segment comprises a group of pictures that begins with an instantaneous decoder refresh frame;
• and a processing unit configured to:
• provide, to the client device, a variant playlist file that identifies a plurality of variant streams each corresponding to a different encoding of a same media presentation;
• track a set of media segments, downloaded by the client device, identified in a first playlist file that corresponds to a first variant stream, from the plurality of variant streams, encoded at a first encoded bitrate;
• receive, from the client device, a request for a second playlist file that identifies a plurality of media segments from a second variant stream, from the plurality of variant streams, encoded at a second encoded bitrate;
• and
• responsive to the second encoded bitrate being higher than the first encoded bitrate:
• determine a number of media segments to include in a set of media segments from the second variant stream that correspond to the tracked set of media segments already downloaded by the client device, the number determined based on an amount of network bandwidth available for the client device;
• identify, for the second playlist file, the set of media segments from the second variant stream that correspond to the tracked set of media segments already downloaded by the client device, the set of media segments from the second variant stream amounting to the determined number;
• and
• provide, to the client device, the second playlist file that identifies the plurality of media segments from the second variant stream including the set of media segments from the second variant stream that correspond to the tracked set of media segments already downloaded by the client device.

A non-transitory computer readable storage medium for switching a client device between media segments corresponding to different encoded bitrates, comprising executable instructions that, when executed by a processor, facilitate performance of operations, comprising:

• providing, to the client device, a first playlist file identifying a first set of media segments from a first variant stream corresponding to a media presentation encoded at a first encoded bitrate, and a second playlist file identifying a second set of media segments from a second variant stream corresponding to the media presentation encoded at a second encoded bitrate, wherein each media segment comprises a group of pictures and is independently decodable without referencing another media segment, and wherein each media segment corresponds to a portion of the media presentation;
• tracking a set of media segments downloaded by the client device, wherein media segments of the tracked set of media segments are encoded at that first encoded bitrate and are identified in the first playlist file;
• receiving, from the client device, a request for the second playlist file;
• and
• responsive to the second encoded bitrate being higher than the first encoded bitrate:
• determining a number of media segments to include in a set of media segments from the second variant stream that correspond to the tracked set of media segments already downloaded by the client device, the number determined based on an amount of network bandwidth available for the client device;
• identifying, for the second playlist file, the set of media segments from the second variant stream that correspond to the tracked set of media segments already downloaded by the client device, the set of media segments from the second variant stream amounting to the determined number;
• and
• providing, to the client device, the second playlist file that identifies the second set of media segments from the second variant stream including the set of media segments from the second variant stream that correspond to the tracked set of media segments already downloaded by the client device.