Speex

The NSpeexEncoder handles legacy or bandwidth-constrained audio encoding for the HoloMIT SDK.

Implementation Details

The encoder inherits from VoiceEncoder (and ultimately BaseWorker) and operates asynchronously using thread-safe queues. It pulls raw audio frames (FloatMemoryChunk) from an input queue, compresses them, and pushes the resulting ByteMemoryChunk to an output queue.

• Implementation: Wraps the NSpeex library.
• Configuration:
  • Band Mode: Wide
  • Quality: 5
• Buffer Size: Dynamically assigned based on the Speex encoder's FrameSize.

Decoder (VoiceDecoder)

Instead of having a separate decoder class, the system uses a unified VoiceDecoder that handles Speex dynamically.

• When instantiated, it prepares a SpeexDecoder in Wide band mode.
• It reads the format from the first packet's metadata (_chunk.Info.Dsi).
• Because the incoming stream is Mono but Unity's spatial audio or multi-channel setups might require more, the decoder duplicates the decoded mono signal across 6 channels into the final FloatMemoryChunk before queueing it for the AudioPreparer.