Vorbis is an open source codec first introduced by Xiph foundation in the year 2002. Vorbis encoder can operate on 8-32 bit PCM audio signals sampled at 8-192 KHz and generates compressed bit-streams having bit-rates in the range of 8 1536 kbps. Vorbis is based on the modified discrete cosine transform and uses vector quantization to represent the transformed coefficients. The compressed bit-stream can be represented in Ogg (container format for file transport) or RTP (for network multicast) packing format. Vorbis is a royalty free codec and has been deployed in gaming and audio broadcasting applications.
- Based on TREMOR open source standard version 1.0.0
- Optimized ASM/C implementation.
- Re-entrant implementation
- C-callable APIs
- Support for 16/24 bit PCM output audio signals sampled at 8 KHz 64 KHz.
- Support for up to 5.1 audio channels.
- Support bit-rates ranging from 8kbps to 1536kbps.
- Supports down-mixing to mono or stereo.
- Supports Interleaved and de-interleaved output.
- Supports decoding of bit-rate peeled streams
- Supports decoding of streams packed using ogg container.
- Supports decoding of Vorbis audio packets from multiplexed streams containing audio, video and any other metadata.
- Supports Little-Endian implementation on ARM
- Optimized for low memory foot print.
- Optional support from 64 to 96KHz sampling rates(Table Memory Increases for this support)
- Optional support for xDM API’s.
- Tested for bit-compliance using a large database of audio test vectors
- Tested for mono, 2-channel, and 5-channel stereo test vectors
- Tested for graceful exit in case of bit-stream related errors or exception.
- Tested for illegal memory access by the module on ARM platform.
- Module is fully interruptible.
- Tested for compliance with register preservation requirements
- Tested for Input buffer corruption
- Tested for I/O buffer alignment requirements
- Tested for multi-instance implementation.
- Tested with scratch contamination at frame boundaries
- Tested for 100% code coverage
- Range validation of all API parameters
- ARM implementation is validated on OMAP3530 (Cortex-A8) and DM6446/DM6467 (ARM926EJ-S) platforms.
ARM9E, ARM11, Cortex-A8, and Cortex-A9