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Specialists in Speech and Audio Software Development

MP3 Audio Decoder

ISO/IEC 11172-3 (MPEG 1) defines methods for compression/decompression of up to two channels of audio data sampled at 32, 44.1 or 48kHz at bit-rates from 32 to 384kbit/s. Three related methods are described referred to as Layer I, II and III. Layer III offers the highest compression for a given audio fidelity but requires the highest complexity. ISO/IEC 13818-3 (MPEG 2) extends the two channel scheme to include sample rates of 16, 22.05 and 24kHz (low sample frequency (LSF) extension) and further defines methods to compress/decompress up to 12 channels of audio data.

The ESPICO implementations support Layers I, II and III as well as the low sample frequency extension decoder. Low memory and MHz requirements allow low power applications to be realised. Extensive testing has been carried out with compliant and non-compliant streams.

Features

• Decodes MPEG1 (ISO/IEC 11172-3) and MPEG2 (ISO/IEC 13818-3) audio bitstreams
• Decodes non-ISO MPEG 2.5 low sample frequency (LSF) extension
• Conforms to ISO/IEC 11172-4:1995 and ISO/IEC 13818-4:2004 standards
• Layers I, II and III are all supported
• Compile time customization options for reduced memory footprint:

 - Sixteen Bit Output

 - Layer I Enable/Disable

 - Layer II Enable/Disable

 - CRC Enable/Disable

• Includes mono, stereo, joint stereo, and dual channel modes

Availability

ESPICO’s optimised solution can be ported to any platform. Platforms supported include:

• ZSP Cores including ZSP400, ZSP500, ZSP800 families
• ARM including Cortex and NeonTM
• MIPS32 74KTM
• Ceva DSP Cores

Applications

MP3 Audio Decoder has numerous applications and is widely used in many products, such as Portable Audio Systems, Wireless, Mobile, Car Audio, Set Top Boxes, Internet Appliances and PDAs.