Title :
A Time-Frequency Hybrid Downmixing Method for AC-3 Decoding
Author :
Hui Li ; Yiwen Wang ; Ping Li
Author_Institution :
State Key Lab. of Electron. Thin Films & Integrated Devices, Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
In this letter, a time-frequency hybrid downmixing method is proposed for AC-3 decoding. The proposed method consists of downmixing frequency coefficients of long blocks and short blocks respectively, computing long and short inverse modified discrete cosine transforms (IMDCTs), and adding operation. Compared with one reported fast frequency-domain downmixing method, the proposed method does not need frequency coefficients conversion between long and short blocks, and has approximately 26% and 32% reduction in numbers of additions and multiplications, respectively.
Keywords :
audio coding; decoding; discrete cosine transforms; inverse transforms; time-frequency analysis; AC-3 decoding; IMDCT; adding operation; audio encoding; audio standards; downmixing frequency coefficients; fast frequency-domain downmixing; frequency coefficients conversion; inverse modified discrete cosine transforms; time-frequency hybrid downmixing method; Decoding; Equations; Frequency conversion; Time-domain analysis; Time-frequency analysis; Transforms; AC-3; decoding; downmixing; inverse modified discrete cosine transform (IMDCT); type-IV discrete cosine transform (DCT-IV);
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2014.2321061
