@coze/uniapp-api
Version:
Official Coze UniApp SDK for seamless AI integration into your applications | 扣子官方 UniApp SDK，助您轻松集成 AI 能力到应用中
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JavaScript
;
/**
* G.711 codec implementation for A-law and μ-law
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.decodeAlaw = decodeAlaw;
exports.decodeUlaw = decodeUlaw;
// A-law to linear PCM conversion table
const ALAW_TO_LINEAR_TABLE = new Int16Array(256);
// μ-law to linear PCM conversion table
const ULAW_TO_LINEAR_TABLE = new Int16Array(256);
// Initialize conversion tables
(function initTables() {
// A-law to linear PCM conversion
for (let i = 0; i < 256; i++) {
const aval = i ^ 0x55;
let t = (aval & 0x0f) << 4;
const seg = (aval & 0x70) >> 4;
if (seg) {
t = (t + 0x108) << (seg - 1);
}
else {
t += 8;
}
ALAW_TO_LINEAR_TABLE[i] = aval & 0x80 ? t : -t;
}
// μ-law to linear PCM conversion
for (let i = 0; i < 256; i++) {
const uval = ~i;
let t = ((uval & 0x0f) << 3) + 0x84;
const seg = (uval & 0x70) >> 4;
t <<= seg;
ULAW_TO_LINEAR_TABLE[i] = uval & 0x80 ? 0x84 - t : t - 0x84;
}
})();
/**
* Converts G.711 A-law encoded data to PCM16 format
* @param {Uint8Array} alawData - A-law encoded data
* @returns {Int16Array} - PCM16 data
*/
function decodeAlaw(alawData) {
const pcmData = new Int16Array(alawData.length);
for (let i = 0; i < alawData.length; i++) {
pcmData[i] = ALAW_TO_LINEAR_TABLE[alawData[i]];
}
return pcmData;
}
/**
* Converts G.711 μ-law encoded data to PCM16 format
* @param {Uint8Array} ulawData - μ-law encoded data
* @returns {Int16Array} - PCM16 data
*/
function decodeUlaw(ulawData) {
const pcmData = new Int16Array(ulawData.length);
for (let i = 0; i < ulawData.length; i++) {
pcmData[i] = ULAW_TO_LINEAR_TABLE[ulawData[i]];
}
return pcmData;
}