@remotion/media-utils/dist/probe-wave-file.js

Utilities for working with media files

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.probeWaveFile = exports.getInt8AsFloat = exports.getInt16AsFloat = void 0;
const fetch_with_cors_catch_1 = require("./fetch-with-cors-catch");
const getUint32 = (bytes, offset) => {
    const val1 = bytes[offset + 3];
    const val2 = bytes[offset + 2];
    const val3 = bytes[offset + 1];
    const val4 = bytes[offset];
    return (val1 << 24) | (val2 << 16) | (val3 << 8) | val4;
};
const getUint16 = (bytes, offset) => {
    const val1 = bytes[offset + 1];
    const val2 = bytes[offset];
    return (val1 << 8) | val2;
};
const getInt16AsFloat = (bytes, offset) => {
    if (offset >= bytes.length) {
        throw new Error(`Tried to read a 16-bit integer from offset ${offset} but the array length is ${bytes.length}`);
    }
    const val1 = bytes[offset + 1];
    const val2 = bytes[offset];
    const int16 = (val1 << 8) | val2;
    return ((int16 << 16) >> 16) / 32768;
};
exports.getInt16AsFloat = getInt16AsFloat;
const getInt8AsFloat = (bytes, offset) => {
    if (offset >= bytes.length) {
        throw new Error(`Tried to read an 8-bit integer from offset ${offset} but the array length is ${bytes.length}`);
    }
    return bytes[offset] / 128;
};
exports.getInt8AsFloat = getInt8AsFloat;
const probeWaveFile = async (src, probeSize = 1024) => {
    const response = await (0, fetch_with_cors_catch_1.fetchWithCorsCatch)(src, {
        headers: {
            range: `bytes=0-${probeSize - 1}`,
        },
    });
    if (response.status === 416) {
        throw new Error(`Tried to read bytes 0-1024 from ${src}, but the response status code was 416 "Range Not Satisfiable". Is the file at least 256 bytes long?`);
    }
    if (response.status !== 206) {
        throw new Error(`Tried to read bytes 0-1024 from ${src}, but the response status code was ${response.status} (expected was 206). This means the server might not support returning a partial response.`);
    }
    const buffer = await response.arrayBuffer();
    const uintArray = new Uint8Array(buffer);
    const shouldBeRiff = new TextDecoder().decode(uintArray.slice(0, 4));
    if (shouldBeRiff !== 'RIFF') {
        throw new Error('getPartialAudioData() requires a WAVE file, but the first bytes are not RIFF. ');
    }
    const size = getUint32(uintArray, 4);
    const shouldBeWAVE = new TextDecoder().decode(uintArray.slice(8, 12));
    if (shouldBeWAVE !== 'WAVE') {
        throw new Error('getPartialAudioData() requires a WAVE file, but the bytes 8-11 are not "WAVE". ');
    }
    const shouldBeFmt = new TextDecoder().decode(uintArray.slice(12, 16));
    if (shouldBeFmt !== 'fmt ') {
        throw new Error('getPartialAudioData() requires a WAVE file, but the bytes 12-15 are not "fmt ". ');
    }
    // const chunkSize = toUint32(uintArray.slice(16, 20));
    const audioFormat = getUint16(uintArray, 20);
    if (audioFormat !== 1) {
        throw new Error('getPartialAudioData() supports only a WAVE file with PCM audio format, but the audio format is not PCM. ');
    }
    const numberOfChannels = getUint16(uintArray, 22);
    const sampleRate = getUint32(uintArray, 24);
    const blockAlign = getUint16(uintArray, 32);
    const bitsPerSample = getUint16(uintArray, 34);
    let offset = 36;
    const shouldBeDataOrList = new TextDecoder().decode(uintArray.slice(offset, offset + 4));
    if (shouldBeDataOrList === 'LIST') {
        const listSize = getUint32(uintArray, 40);
        offset += listSize;
        offset += 8;
    }
    if (offset + 4 > probeSize) {
        return (0, exports.probeWaveFile)(src, offset + 4);
    }
    const shouldBeData = new TextDecoder().decode(uintArray.slice(offset, offset + 4));
    if (shouldBeData !== 'data') {
        throw new Error(`getPartialAudioData() requires a WAVE file, but the bytes ${offset}-${offset + 4} are not "data". `);
    }
    const dataSize = getUint32(uintArray, offset + 4);
    return {
        dataOffset: offset + 8,
        bitsPerSample,
        numberOfChannels,
        sampleRate,
        blockAlign,
        fileSize: size,
        durationInSeconds: dataSize / (sampleRate * blockAlign),
    };
};
exports.probeWaveFile = probeWaveFile;