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# Changelog

## October 20, 2026

## Neutral audio expression

**Audio measurements now score a `neutral` expression.** The `expressions` array returned by [audio upload](/expression-measurement/docs/audio/upload) and [audio realtime](/expression-measurement/docs/audio/realtime) draws from 415 names, up from 414. The full list is in [Audio measurements](/expression-measurement/docs/audio/measurements#expressions).

## October 6, 2026

## Expression Measurement API launch

**The Expression Measurement API is now available in limited release.** It measures emotional expression in speech and in faces, from uploaded audio and images or live audio and video streams. [Contact our team](https://www.hume.ai/sales-form) to request access, then start with the [overview](/expression-measurement/docs/overview).

* **Audio endpoints.** [Audio upload](/expression-measurement/docs/audio/upload) measures an audio file in one request, and [audio realtime](/expression-measurement/docs/audio/realtime) measures audio as you stream it over a WebSocket. Each measurement scores the `expressions` and `voice_attributes` of a window of speech.
* **Video endpoints.** [Image upload](/expression-measurement/docs/video/upload) measures JPEG images in one request, and [video realtime](/expression-measurement/docs/video/realtime) measures video as you stream it, one JPEG frame at a time. Each face detected gets a bounding box, and the largest faces in each image, 2 by default, also get scores for their `expressions` and `descriptions`.
* **Run endpoints.** [Runs](/expression-measurement/docs/runs) return the status, configuration, reported problems, and [billable seconds](/expression-measurement/docs/billing) of each upload request and realtime session.
* **SDKs.** Python (`hume-expression-measurement`) and Node.js (`@humeai/expression-measurement-node`) SDKs cover every endpoint. See the [Python quickstart](/expression-measurement/docs/quickstart/python) and the [Node.js quickstart](/expression-measurement/docs/quickstart/nodejs).