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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),




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