In this paper, we perform a fixed-point analysis for Dolby AC-3 audio decoding algorighm, and determine the suitable multiplier wordlength (say, N) satisfying the required sound quality. After that, based on the similar simulations, we try to reduce the accumulator wordlength from the usual (8+2N) to (g + N + r) where g is the wordlength for overflow guard bits and r is the wordlength for rounding with the condition r < N. To show that r bit rounding is enough, error signal waveforms are shown which are obtained by subtracting the floating-point simulation generated PCM samples from the r bit rounded fixed-point simulation generated PCM samples. In addition to them, frequency magnitude plots of the decoded PCM samples are shown, and compared with those of the floating-point decoded PCM samples.
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机译:在本文中,我们对杜比AC-3音频解码算法进行了一个定点分析,并确定满足所需音质的合适的乘法机字长(例如,n)。之后,基于类似的模拟,我们尝试将累加器WordLength从通常的(8 + 2n)到(g + n + r)减少,其中g是溢出保护位的字长,并且R是舍入的WordLength条件R 展开▼