SmartJukebox: An Efficient and High-Quality MPEG-2 AAC Encoder

*Multimedia Research Laboratories This paper describes high-quality and processor-efficient software implementation of an MPEG-2 AAC LC Profile encoder utilized in “SmartJukebox,” music jukebox software. MDCT and quantization processing are accelerated by 21.3% and 19.0%, respectively, through the use of SIMD instructions. In addition, psycho-acoustic analysis in the MDCT domain makes the use of FFTs unnecessary and reduces the computational cost of the analysis by 56.0%. The results of subjective quality tests show that better sound quality is provided by greater efficiency in quantization processing and Huffman coding. All of this results in high-quality and processor-efficient software implementation of an MPEG-2 AAC encoder. Subjective test results show that the sound quality achieved at 96kbps/stereo is equivalent to that of MP3 at 128kbps/stereo. The encoder works 13 times faster than real time for stereo encoding on an 800MHz Pentium III processor.