Files
element-web/src/workers/playback.worker.ts
David Langley 69ee8fd96a Change License: AGPL + Element Commercial (#28856)
* Add commercial licence and update config files

* Update license in headers

* Revert "Update license in headers"

This reverts commit 7ed7949485.

* Update only spdx id

* Remove LicenseRef- from package.json

LicenseRef- no longer allowed in npm v3 package.json
This fixes the warning in the logs and failing build check.
2025-01-06 11:18:54 +00:00

35 lines
1.2 KiB
TypeScript

/*
Copyright 2024 New Vector Ltd.
Copyright 2022 The Matrix.org Foundation C.I.C.
SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
Please see LICENSE files in the repository root for full details.
*/
import { WorkerPayload } from "./worker";
import { arrayRescale, arraySmoothingResample } from "../utils/arrays";
import { PLAYBACK_WAVEFORM_SAMPLES } from "../audio/consts";
const ctx: Worker = self as any;
export interface Request {
data: number[];
}
export interface Response {
waveform: number[];
}
ctx.addEventListener("message", async (event: MessageEvent<Request & WorkerPayload>): Promise<void> => {
const { seq, data } = event.data;
// First, convert negative amplitudes to positive so we don't detect zero as "noisy".
const noiseWaveform = data.map((v) => Math.abs(v));
// Then, we'll resample the waveform using a smoothing approach so we can keep the same rough shape.
// We also rescale the waveform to be 0-1 so we end up with a clamped waveform to rely upon.
const waveform = arrayRescale(arraySmoothingResample(noiseWaveform, PLAYBACK_WAVEFORM_SAMPLES), 0, 1);
ctx.postMessage({ seq, waveform });
});