Lossless Audio Coding revisited

Sporer T. Lossless Audio Coding revisited. In: Express Paper. Audio Engineering Society; 2026. Paper 443. Available from: https://aes.org/publications/elibrary-page/?id=23262

@inproceedings{Sporer2026_23262,
  author = {Sporer, Thomas},
  title = {{Lossless Audio Coding revisited}},
  note = {Paper 443},
  year = {2026},
  month = may,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=23262}
}

TY  - CPAPER
TI  - Lossless Audio Coding revisited
AU  - Sporer, Thomas
M1  - Paper 443
PY  - 2026
DA  - 2026/05/28
UR  - https://aes.org/publications/elibrary-page/?id=23262
PB  - Audio Engineering Society
LA  - en
AB  - MPEG-4 SLS (scalable lossless coding) was published more than 20 years ago. In the meantime, several tools to improve coding efficiency and flexibility have been invented. Currently, in MPEG WG6 (audio coding) there are two standardization activities on lossless audio coding: Audio Coding for Machines (ACoM) and Biomedical and general waveform signal coding (BWC). ACoM phase 1 originally was targeted only towards lossless storage formats for training of machine listening schemes, but additional uses cases like user generated content analysis, live stream content analysis, and artistic creation have been added. The focus was extended to the transmission of audio data from microphone (arrays) to central processing units. BWC is a joint activity with ITU-R SG21. While ACoM started with a large number of use cases and includes the specification of a rich set of metadata BWC started with a focus on medical data like electroencephalogram (EEG) and electrocardiogram (ECG). However, BWC can be used for audio signals, too and medical data coding are on the list of use cases for ACoM. The call for proposals (CfP) for ACoM was completed in January 2026. Two proposals, both outperforming MPEG-4 SLS, have been submitted. Both proposals are based on reused and optimized core codecs from BWC. Currently, MPEG audio investigates how the ACoM proposals can be merged into BWC. This merge-process must be completed by end of April 2026. This paper gives details about ACoM use cases, the ACoM CfP process, the results of the CfP and results from the merge process.
ER  -