POST-ENCODING BITRATE REDUCTION OF MULTIPLE OBJECT AUDIO

A post-encoding bitrate reduction method for generating one more scaled compressed bitstreams from a single encoded plenary file. The plenary file contains multiple audio object files that were encoded separately using a scalable encoding process having fine-grained scalability that ranks bits in each data frame of the encoded audio object files in an order of psychoacoustic importance to human hearing. The plenary file is generated at the plenary bitrate by combining the plurality of independently encoded audio object files and corresponding hierarchical metadata. A first scaled compressed bitstream is constructed at a first target bitrate from the plenary file, and a second scaled compressed bitstream is constructed at a second target bitrate from the plenary file such that multiple scaled bitstreams at different target bitrates are obtained from the single plenary file without any re-encoding of the plurality of encoded audio object files. The first target bitrate and the second target bitrate are different from each other and are both less than the plenary bitrate.