Encoder buffer having an effective size which varies automatically with the channel bit-rate
March 17, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesDPCM system with rate-of-fill control of buffer occupancy Code converting system and method for band compression of digital signals Adaptive buffer/quantizer control for transform video coders Buffer control for variable bit-rate channel Preamble length adjustment method in communication network and independent synchronization type serial data communication device Buffer fullness indicator Patent #: 5365552 InventorApplicationNo. 214910 filed on 03/17/1994US Classes:375/240, BANDWIDTH REDUCTION OR EXPANSION370/468, Assignment of variable bandwidth or time period for transmission or reception375/240.05, Feed back375/242PULSE CODE MODULATIONExaminersPrimary: Chin, StephenAssistant: Ghebretinsae, T. Attorney, Agent or FirmInternational ClassH04B 001/66AbstractThe effective (or logical) size of the encoder buffer in a video transmission system is varied with the transmission bit-rate. Also, a minimum fill level is maintained in the encoder buffer whenever the transmission rate is too high to assure otherwise that the decoder buffer will not overflow or underflow. The encoding rate is varied so as to maintain a fill level in the encoder buffer within limits. In the preferred embodiment, the logical encoder buffer has a size which is maintained at RƊT(1-m1)-M, where R is the average transmission bit-rate, which may vary, ƊT is the fixed delay between the encoding and decoding processes for a transmitted video signal, R(1-mm) is the minimum instantaneous transmission rate that the communication system achieves at average rate R, and M is the maximum total buffer storage in the communication system. When the decoder buffer has a size less than RƊT(1+m2), where R(1+m2) is the maximum instantaneous transmission rate at average rate R, the encoder buffer fill level is maintained above a minimum level that is equal to the amount by which the decoder buffer is less than RƊT(1+m2).Other References
| |
