WMA Decoder
Introduction
Windows Media Audio (WMA) is a audio codec developed by Microsoft. WMA consists of three different codecs, namely WMA standard (known as WMA), WMA professional (known as WMA pro) and WMA lossless decoder.


WMA V9 defines various codec types known as 1) WMA Standard 2) WMA Professional 3) WMA Voice and 4) WMA Lossless. WMA V9 also defines four device profiles for WMA Standard codec known as

1) WMA L1: Only 44.1 KHz is supported upto 160 kbps.
2) WMA L2: Includes WMA L1, plus upto 48 KHz sampling rate at 256 kbps.
3) WMA L3: Full implementation. Includes WMA L1 and WMA L2 plus bitrates of 192-320 kbps for both 44.1 and 48 KHz sampling rates.
4) WMA L: PC only profile intended to showcase full codec capabilities and is not intended for devices.
5) WMA Pro M0: Sampling frquency less than 48 Khz, support upto 192 kbps and mono and stereo channels.
6) WMA Pro M1: Sampling frquency less than 48 Khz, support upto 384 kbps and multi channel support up to 5.1.
7) WMA Pro M2: Sampling frequency less than 96 Khz, support upto 768 kbps and multi channel support up to 5.1.
8) WMA Pro M3: Sampling frequency less than 96 Khz, support upto 1.5 Mbps and multi channel support up to 7.1.
9) WMA Pro M: PC profile supports all the sampling frequency, bit rate and channels, intended to showcase full codec capabilities.
Salient Features

  • WMA Standard
    • Supports WMA 7,8, 9, 9.1 and 10
    • Profiles – L1 to L3
    • Sampling frequency : 8 – 48 Khz
    • Channels: stereo
    • All bitrates of WMA L3 profile
  • WMA Pro
    • Sampling frequency : 8 – 96 Khz
    • Channels – Upto 7.1
    • Profile – M0 to M3
    • PCM resolution – 16 and 24 bits
Benefits
  • Low Mhz and memory foot print
  • Re-sync support for fast forward/rewind
  • Multi instance and re-entrant implementation
  • XDM API support for TI processors
  • API supports push model type
Applications
  • Automotive Infotainment
  • Portable audio players
  • Streaming
  • Mobile phones
  • Gaming consoles
  • Broadcast audio
Platforms
  • TI
    • TMS320C67x, TMS320C66x
  • ARM
    • ARM9, ARM11,Cortex A8

Case studies

Developing an Asynchronous Sample Rate Converter

Designing an Asynchronous Sample Rate converter that offers high THD and low ripple across a range of frequencies is no mean achievement. We not only designed the ASRC but implemented it with low MHz on a fixed point processor.

Video codecs on a multi-core highly-parallel custom core

We worked with SiliconHive (now part of Intel) to develop High Definition video codecs that are designed to run optimally on a multi-core environment. Our contribution also included efficient coding for a VLIW core and algorithmic innovations to address memory bandwidth constraints.

Showcase

Android Auto projection on Telechip TCC8930 running WinCE 7.0
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RACE Media & Connectivity IVI suite
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