aware(5) aware(5) NAME aware, AwareIntro - Aware(R), Inc. scalable audio compression software engines Aware Compression Aware has implemented audio compression software engines enabling users of Silicon Graphics(R) workstations to reduce the storage size and transmission bandwidth required for audio data. The products are compatible with third-party applications which incorporate audio in the Silicon Graphics computing environment. Scalable operation provides the ability to control processor loading for audio playback concurrent with other computational tasks. MPEG Audio Compression Engine Aware scalable MPEG (Motion Pictures Experts Group) compression software provides advanced psychoacoustic processing for compression of high quality audio (up to 48 kHz sampling rate) in authoring, publishing, and large audio database applications. Real-time operation encodes audio while recording and provides moderate compression ratios. Non-real-time operation invokes advanced psychoacoustic modeling for high compression ratios. Encoding bit-rates range from 32 kbits/second to 448 kbits per second (corresponding to compression ratios as high as 48:1). The software MPEG decompression engine is included as a standard feature of the IRIS Digital Media Execution Environment (dmedia_eoe). Standard tools like soundplayer(1) and movieplayer(1) use this software to play back MPEG audio tracks. The software MPEG compression engine is also included with the IRIS Digital Media Execution Environment (dmedia_eoe). Standard tools like soundeditor(1) and soundtrack(1) use this software to record MPEG audio tracks. Aware MultiRate (TM) Compression Engine Aware MultiRate compression provides a compression solution for studio and audio production applications requiring lossless (perfectly invertible) and near-lossless coding and using low processor loading. Lossless mode typically reduces storage requirements by 2:1 to 3:1. Near-lossless operation achieves even greater storage savings while retaining a 90 dB signal to noise ratio. Real-time encoding of audio at 8, 11, 16, 22, and 44.1 kHz sampling rates is supported. Scalable encoding and decoding operation provides control of processor loading during playback. Installation of AudioProducer includes Aware's AudioPlayback software. The MultiRate decoder runs in real-time at sampling rates up to 48 kHz. Installation of the decoder enables real-time playback of compressed audio which was encoded with the Aware AudioPublisher or the Aware AudioProducer. Scalable decoding operation provides the ability to control processor loading used for playback, and enables special functions such as fast playback to speed search through compressed audio libraries. The software necessary to perform Aware MultiRate audio compression or decompression is included with the standard IRIS Digital Media Execution Environment (dmedia_eoe). However, both of these engines are locked by default. You must obtain a license from Aware in order to unlock the compression or decompression engines. Please note that as of Irix 6.x, Aware no longer sells licenses for the MultiRate audio codec. SGI still provides the libraries for backwards compatibility, and as a convenience to users who have previously purchased MultiRate audio codec licenses from Aware. MPEG Audio Compression Specifications Algorithm: ISO/MPEG Layer I and II low bitrate psychoacoustic compression Developer Support: Audio File Library (AFaware(3dm)) Compression Library (CLintro(3dm)) Encoder Input: Format 16 bit linear audio samples, mono or stereo Sample Rates 48, 44.1, 32 kHz Decoder Output: Format 16 bit linear audio samples, mono or stereo Sample Rates 48, 44.1, 32, 24, 22.05, 16, 11.025 Compression Ratios: 2.2:1 to 48:1, selectable via bitrate parameter Bitrates (kbits/sec): Layer I: 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448 Layer II: 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384 Channel Processing: mono, stereo, joint stereo, dual channel Scalable Processing: Controlled reduction of CPU usage by parametric control of frequency response, signal to noise ratio, and mono decoding of stereo. Aware MultiRate Compression Specifications Algorithm: Aware MultiRate I high resolution audio compression Developer Support: Audio File Library (AFaware(3dm)) Compression Library (CLintro(3dm)) Encoder Input: Format 16 bit linear audio samples, mono or stereo Sample Rates 48, 44.1, 32, 22.05, 16, 11.025, 8 kHz Decoder Output: Format 16 bit linear audio samples, mono or stereo Sample Rates 48, 44.1, 32, 24, 22.05, 16, 11.025, 8 kHz Compression Ratios: MultiRate lossless (perfectly invertible mode): 2:1 to 3:1 typical MultiRate near lossless (90+dB SNR) mode: 2.5:1 to 4:1 typical Channel Processing: mono, stereo, dual channel Scalable Processing: Controlled reduction of CPU usage by parametric control of frequency response, signal to noise ratio, and mono decoding of stereo. SEE ALSO MPEG(4) soundplayer(1), movieplayer(1), moviemaster(1), AFintro(3dm), AFaware(3dm), CLintro(3dm), CLaware(3dm), Page 4