基于DRA和AAC的MDCT/IMDCT预回声抑制比较  

Compare Pre-echo Elimination Based on MDCT/IMDCT of DRA and AAC

作　　者：吴凤燕[1] 刘守训[1] 王翾[1] 

机构地区：[1]中国传媒大学信息工程学院,北京100024

出　　处：《电声技术》2010年第7期65-68,共4页Audio Engineering

摘　　要：预回声是音频编解码中的重要问题,它是因时间分辨率不足造成量化噪声的时域扩散而引起的,将严重影响声音质量,特别是在瞬态信号中。就基于DRA和AAC的MDCT/IMDCT,从理论和试验上比较和分析了长窗、短窗、暂态窗抑制预回声的有效性。在相同的条件下,暂态窗和短窗预回声的抑制效果远远好于长窗,而暂态窗又好于短窗。Due to spread of quantization noise in time domain from low time resolution, pre-echo, being an important problem, would deteriorate the sound quality, especially the transient signals. Based on the MDCT/IMDCT of DRA and AAC, the effect of long window, short window and brief window on eliminating pre-eeho on the basis of theory and simulation tests are discussed and analyzed. Simulation tests demonstrate a much better performance by the brief window and the short window in eliminating the pre-echo on condition that the other variables stay the same, than by long window. In addition, tests by the brief window better than that by the short one.

关 键 词：DRA AAC MDCT/IMDCT 预回声 暂态窗 短窗 长窗 

分 类 号：TN912[电子电信—通信与信息系统]