Binaural NGA Renderer (NGA-Binaural)

The Binaural NGA Renderer (NGA-Binaural) is an addon that provides binaural rendering of ADM files by using the EBU ADM Renderer (EAR) to create virtual loudspeaker signals. The EAR will be installed together with this addon, if it is not already present. This Binaural NGA Renderer provides an implementation of the rendering structure, as well as the optimization approaches that are described in the the AES paper "Optimized binaural rendering of Next Generation Audio using virtual loudspeaker setups".

Further descriptions of the EAR algorithms and functionalities can be found in EBU Tech 3388.

Test files

A initial set of ADM files to test the NGA-Binaural can be found under

Installation

To install the latest release from github:

$ git clone the repository
$ pip install path/to/repository

Python versions

NGA-Binaural supports Python 2.7 and Python >=3.6 and runs on all major platforms (Linux, Mac OSX, Windows).

Getting started

The NGA-Binaural comes with the following command line tool:

nga-binaural

Command line renderer

usage: nga-binaural [-h] [-d]
                    [-s target_system]
                    [--output-gain-db gain_db] [--fail-on-overload]
                    [--enable-block-duration-fix] [--programme id]
                    [--comp-object id]
                    [--apply-conversion {to_cartesian,to_polar}] 
                    [--peak_normalization] [--strict]
                    input_file output_file

Binaural NGA Renderer

positional arguments:
  input_file
  output_file

optional arguments:
  -h, --help            show this help message and exit
  -d, --debug           print debug information when an error occurs
  --output-gain-db gain_db
                        output gain in dB (default: 0)
  --fail-on-overload, -c
                        fail if an overload condition is detected in the
                        output
  --enable-block-duration-fix
                        automatically try to fix faulty block format durations
  --programme id        select an audioProgramme to render by ID
  --comp-object id      select an audioObject by ID from a complementary group
  --apply-conversion {to_cartesian,to_polar}
                        Apply conversion to Objects audioBlockFormats before
                        rendering
  --peak_normalization, -pn
                        perform a peak normalization of the output
  --strict              treat unknown ADM attributes as errors

To render an ADM file, the following two parameters must be given:

the name of the input file
the name of the output file

For example nga-binaural input.wav output_binaural.wav will render the BW64/ADM file input.wav and store the result in output_binaural.wav.

-s followed by a target, BS2051-output format can be used to render to a specific virtual loudspeaker setup. Otherwise, a virtual 49 speaker setup will be used that is optimized for rendering quality, but requires a lot of computational cost.

--fail-on-overload makes the rendering process fail in case an overload in the output channels occurs to ensure any signal clipping doesn't go unnoticed. Use --output-gain-db to adjust the output gain.

--enable-block-duration-fix automatically fixes durations of audioBlockFormats in case they are not continuous. Please note that the proper way to handle this situation is to fix the input file.

--strict enables strict ADM parsing mode. Some of the currently available ADM/BW64 files may not strictly adhere to the BS.2076 specification, for example by including xml attributes that are not part of the standard. The default behaviour is to output a warning and continue processing. When strict mode is enabled, warnings are turned into errors and processing is stopped.

Please note that, depending on the size of the file, it may take some time to render the file. At the time of writing, the parsing of the ADM XML data is relatively slow when the ADM is large (>= a few megabytes).

npinto / binaural_nga_renderer