應科院ARM9E
MPEG-4 BSAC 音頻解碼器(暫時只提供英文版本) |
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Processor
ARM ARM9E family and above with DSP extensions
Background
MPEG-4 BSAC (Bit Sliced Arithmetic Coding) is one of the
audio coding tools specified in MPEG ISO/IEC 14496-3, Part3
Audio. The BSAC technique is used instead of the Huffman
coding in the AAC audio coder to provide scalable bitrate
coding during transportation.
Audio source can be encoded at the full bitrate and that
can be subsequently reduced along the transportation chain
according to channel capacity.
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Supported
sampling frequencies (Hz): 48K, 44.1K, 32K, 24K, 22.05K,
16K, 12K, 11.025K, 8K |
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Bitrate
scalability per channel: from 16kbps to 64kbps with
1kbps step size |
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Provides
mono and stereo decoding |
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| ASTRI
Specific Features |
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Provides
three operating options to suit different processing
loading requirements:
– HQ (High Quality, full processing loading)
– LP (Low Power, 0.8 full processing loading
)
– VLP (Very Low Power, 0.6 full processing loading) |
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Provides
information on bitrate, sampling rate and number of
channels after each successful decoding frame |
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Provides
API for streaming application |
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Accepts
raw BSAC stream from MPEG-4 audio container |
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OS
compatibility: Embedded Linux (Monta Vista, Candenux),
Non-OS, ARM RealView |
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Memory
requirements: 165KByte (Program and Data) |
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| Performance |
| ASTRI
ARM9E MPEG-4 BSAC decoder is optimized for the ARM9E architecture.
The performance is depended on several factors of the target
ARM9E platform: |
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I-Cache
size |
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D-Cache
size |
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SDRAM
speed |
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Availability of TCM |
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| Please
make enquires on the performance for a specific ARM9E platform. |
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