alphartc

AlphaRTC Runtime

This directory contains the prebuilt AlphaRTC runtime used by the emulator. The binaries target 64-bit Linux and are stored with Git LFS.

Layout

alphartc/
|-- dll/       ONNX inference and ONNX Runtime shared libraries
|-- exe/       GCC and Python-inference peer connection executables
`-- pyinfer/   Python wrapper and bandwidth-estimator adapter

The two executable entry points serve different estimators:

• exe/peerconnection_gcc runs the built-in GCC estimator.
• pyinfer/peerconnection_serverless starts exe/peerconnection_serverless_pyinfer and exchanges packet statistics and bandwidth estimates with a Python Estimator.

Retrieve the Runtime

Install Git LFS before cloning or pulling the runtime files:

git lfs install
git lfs pull --include="alphartc/**"

Verify that the executable files are present rather than LFS pointer files:

file alphartc/exe/peerconnection_gcc
file alphartc/exe/peerconnection_serverless_pyinfer

Both commands should report 64-bit ELF files.

Run a Peer

Each entry point expects an AlphaRTC serverless JSON configuration as its first argument.

Run the built-in GCC estimator:

alphartc/exe/peerconnection_gcc /path/to/peer_config.json

Run the default Python estimator:

LD_LIBRARY_PATH="$PWD/alphartc/dll${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}" \
  python3 alphartc/pyinfer/peerconnection_serverless \
  /path/to/peer_config.json

The project-level emulator_call module normally prepares these configuration files, sets the required environment, and starts both peers.

Use a Custom Python Estimator

Set ALPHARTC_ESTIMATOR_DIR to a directory containing BandwidthEstimator.py. That module must export an Estimator class with the following interface:

class Estimator:
    def report_states(self, stats: dict):
        ...

    def get_estimated_bandwidth(self):
        ...

get_estimated_bandwidth() must return the target bitrate in bits per second.

LD_LIBRARY_PATH="$PWD/alphartc/dll${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}" \
ALPHARTC_ESTIMATOR_DIR="$PWD/models/Gemini" \
  python3 alphartc/pyinfer/peerconnection_serverless \
  /path/to/peer_config.json

Runtime Dependencies

The prebuilt runtime requires a compatible 64-bit Linux system, Python 3 for Python-based estimators, and the system libraries reported by ldd. The ONNX libraries in dll/ must be available through LD_LIBRARY_PATH when using the Python-inference executable.