| 摘要 |
A system includes a content creator (12), a transmitting source (14), and a receiver platform (16) for communicating enhancement data associated with audio/video content according to a protocol without layering capability. A receiver platform (16) detects for a first announcement and a second announcement (402), the first announcement being associated with non-layered enhancement data, and the second announcement being associated with layered enhancement data having a plurality of layers. Each layer includes one or mo re sources of trigger files or one or more sources of resource files. Alternatives presented in the second announcement are examined (408), the alternatives containing different collections of the layers of enhancement data. One of the alternatives in the second announcement is selected (410) based on the capacity of the second receiver platform. One or more layers containing respective trigger files and resource files associated with the selected alternative are received (412). The enhancement data may include enhancement data according to an Advanced Television Enhancement Forum Specification. |
