Method, system, and client for streaming media service

A system for a streaming media service, the system comprising:

• a client and a server, wherein
• the client is configured to:
• obtain a media presentation description file, wherein the media presentation description file comprises a priority level of a coding representation group of media,
• select a coding representation group according to the priority level of the coding representation group and a current network bandwidth,
• select one coding representation from each selected coding representation group, and
• request, according to address information that is of the selected coding representation and is obtained by parsing the media presentation description file, a media segment of the coding representation from a server that is indicated by the address information;
• and
• the server is configured to:
• pre-store media segments of different representations.

A client, comprising:

• an obtaining unit, configured to obtain a media presentation description file, wherein the media presentation description file comprises a priority level of a coding representation group of media;
• a selecting unit, configured to select a coding representation group according to the priority level of the coding representation group and a current network bandwidth, wherein the priority level of the coding representation group is obtained by the obtaining unit;
• and select one coding representation from each selected coding representation group;
• and
• a requesting unit, configured to request, according to address information that is of the selected coding representation and is obtained by parsing the media presentation description file that is obtained by the obtaining unit, a media segment of the coding representation from a server that is indicated by the address information.