Multi-channel HE-AAC Audio decoder
Project Objective:
Based on the most efficient audio compression technology, the HE-AAC decoder engine was developed for a leading FPGA Video Codecs IP Provider.
The customer was in need of a AAC Audio decode engine (software) that could be bundled with their FPGA based Video codecs for a complete audio / video processing hardware based on Xilinx ZynQ platform.
The project needed real-time decoding of at least 8 inputs of HE-AAC Stereo or 4 inputs of 5.1 Audio contained in multiple transport formats.
Customer:
Technical Challenges:
- Software Decoding of multiple inputs of HE-AAC Audio (Stereo and 5.1) streams to support real-time playback. No hardware acceleration from FPGA was available.
- Synchronisation between two asynchronous systems - Xilinx Programmable Logic system for Video Codec IP and Processor System for audio decoding in the ARM cores.
- Efficient utilisation of the dual cores (Cortex A9 ARM) in a Non-SMP OS (FreeRTOS) Environment.
Solution Offered:
- Real-time decoding and playback of 8 channels of HE-AAC Stereo Or 4 channels of 5.1 Audio was achieved.
- Interrupt and shared memory driven Inter-core communication between two ARM cores in a Non-SMP OS system.
- Provision for doubling the channel count (by utilising both the ARM cores for parallel operation).
- With the audio decoding being offloaded to the Processor system, the FPGA was entirely available for accommodating more IP blocks.
- Integration of the Audio and Video Processing systems with ASI Inputs (MPEG-TS) and SDI Outputs (Decoded samples)
Technologies / Tools used:
- Supported Codec Formats: AAC-LC, HE-AAC v1/v2 and AAC-ELD
- Supported Transport Formats: ADTS, LATM/LOAS and Raw
- PicoZed board with 7Z015 SoM module
- ASI Input with MPEG-TS Transport
- SDI Out for Decoded Video and Audio
- Xilinx ZynQ SoC (FPGA + Dual Core Cortex A9)
- Xilinx SDK for software development
- Vivado Suite for RTL Synthesis and Integration
Outcome:
A High end Audio / Video Modular solution for use by Broadcast & Streaming companies.
Do reach us at sales@intecoretech.com to know more about the FPGA based HE-AAC decoder case study.
