@echogarden/wave-codec/dist/encodings/Hex.js

A fully-featured WAVE format encoder and decoder. Written in pure TypeScript.

import { decodeAscii } from './Ascii.js';
export function encodeHex(buffer) {
    const asciiBuffer = encodeHexAsAsciiBuffer(buffer);
    return decodeAscii(asciiBuffer);
}
export function encodeHexAsAsciiBuffer(buffer) {
    const bufferLen = buffer.length;
    const charCodes = new Uint8Array(bufferLen * 2);
    let readOffset = 0;
    let writeOffset = 0;
    while (readOffset < bufferLen) {
        const value = buffer[readOffset++];
        const valueHigh4Bits = (value >>> 4) & 0xf;
        const valueLow4Bits = value & 0xf;
        charCodes[writeOffset++] = hexCharCodeLookup[valueHigh4Bits];
        charCodes[writeOffset++] = hexCharCodeLookup[valueLow4Bits];
    }
    return charCodes;
}
export function decodeHex(hexString) {
    const hexLength = hexString.length;
    if (hexLength % 2 !== 0) {
        throw new Error(`Hexadecimal string doesn't have an even number of characters`);
    }
    const buffer = new Uint8Array(hexLength / 2);
    let readOffset = 0;
    let writeOffset = 0;
    while (readOffset < hexLength) {
        const valueHigh4Bits = hexCharCodeToValue(hexString.charCodeAt(readOffset++));
        const valueLow4Bits = hexCharCodeToValue(hexString.charCodeAt(readOffset++));
        const value = (valueHigh4Bits << 4) | valueLow4Bits;
        buffer[writeOffset++] = value;
    }
    return buffer;
}
function hexCharCodeToValue(hexCharCode) {
    if (hexCharCode >= 48 && hexCharCode <= 57) { // '0'..'9'
        return hexCharCode - 48;
    }
    else if (hexCharCode >= 97 && hexCharCode <= 102) { // 'a'..'f'
        return 10 + hexCharCode - 97;
    }
    else if (hexCharCode >= 65 && hexCharCode <= 70) { // 'A'..'F'
        return 10 + hexCharCode - 65;
    }
    else {
        throw new Error(`Can't decode character '${String.fromCharCode(hexCharCode)}' (code: ${hexCharCode}) as hexadecimal`);
    }
}
const hexCharLookup = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'];
const hexCharCodeLookup = new Uint8Array([48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 97, 98, 99, 100, 101, 102]);
//# sourceMappingURL=Hex.js.map