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发表于 2016-12-31 17:32:27
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https://www.helixcommunity.org/projects/datatype/mp3dec
The Helix MP3 Decoder
The Helix MP3 decoder provides MPEG-compliant decoding of MP3 content. Both floating-point and fixed-point decoder implementations are available. The fixed-point decoder is optimized especially for ARM processors but can run on any 32-bit fixed-point processor which can perform a long multiply operation (two 32-bit inputs generating a 64-bit result) and long multiply-accumulate (long multiply with 64-bit accumulator).
Key Features
[li]Pure 32-bit fixed-point implementation[/li][li]High-quality C reference code for porting to new platforms[/li][li]Optimized for ARM processors[/li][li]Fully reentrant and statically linkable[/li][li]Optional C++ API for compatibility with Helix clients[/li][li]Designed for high performance and low power consumption in handheld and mobile devices[/li][li]Full layer 3 support forMPEG1 layer 3 - sampling frequencies: 48 KHz, 44.1 KHz, 32 KHz[/li][li]MPEG2 layer 3 - sampling frequencies: 24 KHz, 22.05 KHz, 16 KHz[/li][li]MPEG2.5 layer 3 - sampling frequencies: 12 KHz, 11.025 KHz, 8 KHz[/li] Supports constant bitrate, variable bitrate, and free bitrate modesSupports mono and all stereo modes (normal stereo, joint stereo, dual-mono)Option to use Intel® IPP performance libraries (if available)[li]Easy to link in either IPP libraries or Helix code[/li]
Technical Specifications
Average CPU Usage
Sample Rate | Channels | Bit Rate | Processor Model [sup](1)[/sup] | ARM7TDMI | ARM9TDMI-REV2 | ARM920T | ARM9E | StrongARM1 | XScale | 48.0 KHz | 2 | 320 Kbps | 30 MHz | 24 MHz | 27 MHz | 20 MHz | 20 MHz | 20 MHz | 44.1 KHz | 2 | 128 Kbps | 26 MHz | 21 MHz | 24 MHz | 17 MHz | 17 MHz | 17 MHz |
(1) Tested with ARMulator, simulated zero-wait-state memory
Memory Usage
[li]ROM = 13446 Bytes (const globals)[/li][li]RAM = 23816 Bytes (heap)Total Data Memory = 37262 Bytes[/li] Code Size = 21000 Bytes (approximately - depends on compiler)
Frequently Asked Questions
Where is the code in CVS?
Where does the build system put the code in my local source tree?
[li]datatype/mp3/codec/fixpt[/li]
How does the build system decide whether to build the fixed-point or floating-point MP3 decoder?
[li]If HELIX_CONFIG_FIXEDPOINT is defined in your profile, it will build the fixed-point decoder. Otherwise it will buil[/li] |
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发表于 2016-2-3 13:28:21
发表于 2019-7-14 14:33:10
