摘要 |
Forward error correction is implemented in a facsimile transmission using adaptive redundancy. The depth of redundancy can change based on a number of factors, including lost packet counts, transport type, facsimile modulation type, call history or facsimile engine state changes. Separate redundancy depths can be implemented for image and for control phases of the facsimile call. Redundancy depth can be increased or decreased during a facsimile call, and may be maintained at an increased level once encountered transmission impediments are overcome. Variable redundancy can be provided for specific portions of the call, such as temporarily increased redundancy during control phases. Adaptive redundancy may be implemented at one or more endpoints or nodes in a packet-switched communication network through which the facsimile call passes. The adaptive redundancy contributes to improving successful facsimile call completion in communication networks that may be prone to error losses. |