66 lines
2.3 KiB
JavaScript
66 lines
2.3 KiB
JavaScript
|
"use strict";
|
||
|
|
Object.defineProperty(exports, "__esModule", { value: true });
|
||
|
|
exports.FactChunk = exports.Format = exports.WaveFormat = void 0;
|
||
|
|
/**
|
||
|
|
* Ref: https://msdn.microsoft.com/en-us/library/windows/desktop/dd317599(v=vs.85).aspx
|
||
|
|
*/
|
||
|
|
var WaveFormat;
|
||
|
|
(function (WaveFormat) {
|
||
|
|
WaveFormat[WaveFormat["PCM"] = 1] = "PCM";
|
||
|
|
// MPEG-4 and AAC Audio Types
|
||
|
|
WaveFormat[WaveFormat["ADPCM"] = 2] = "ADPCM";
|
||
|
|
WaveFormat[WaveFormat["IEEE_FLOAT"] = 3] = "IEEE_FLOAT";
|
||
|
|
WaveFormat[WaveFormat["MPEG_ADTS_AAC"] = 5632] = "MPEG_ADTS_AAC";
|
||
|
|
WaveFormat[WaveFormat["MPEG_LOAS"] = 5634] = "MPEG_LOAS";
|
||
|
|
WaveFormat[WaveFormat["RAW_AAC1"] = 255] = "RAW_AAC1";
|
||
|
|
// Dolby Audio Types
|
||
|
|
WaveFormat[WaveFormat["DOLBY_AC3_SPDIF"] = 146] = "DOLBY_AC3_SPDIF";
|
||
|
|
WaveFormat[WaveFormat["DVM"] = 8192] = "DVM";
|
||
|
|
WaveFormat[WaveFormat["RAW_SPORT"] = 576] = "RAW_SPORT";
|
||
|
|
WaveFormat[WaveFormat["ESST_AC3"] = 577] = "ESST_AC3";
|
||
|
|
WaveFormat[WaveFormat["DRM"] = 9] = "DRM";
|
||
|
|
WaveFormat[WaveFormat["DTS2"] = 8193] = "DTS2";
|
||
|
|
WaveFormat[WaveFormat["MPEG"] = 80] = "MPEG";
|
||
|
|
})(WaveFormat = exports.WaveFormat || (exports.WaveFormat = {}));
|
||
|
|
/**
|
||
|
|
* format chunk; chunk-id is "fmt "
|
||
|
|
* http://soundfile.sapp.org/doc/WaveFormat/
|
||
|
|
*/
|
||
|
|
class Format {
|
||
|
|
constructor(header) {
|
||
|
|
if (header.chunkSize < 16)
|
||
|
|
throw new Error('Invalid chunk size');
|
||
|
|
this.len = header.chunkSize;
|
||
|
|
}
|
||
|
|
get(buf, off) {
|
||
|
|
return {
|
||
|
|
wFormatTag: buf.readUInt16LE(off),
|
||
|
|
nChannels: buf.readUInt16LE(off + 2),
|
||
|
|
nSamplesPerSec: buf.readUInt32LE(off + 4),
|
||
|
|
nAvgBytesPerSec: buf.readUInt32LE(off + 8),
|
||
|
|
nBlockAlign: buf.readUInt16LE(off + 12),
|
||
|
|
wBitsPerSample: buf.readUInt16LE(off + 14)
|
||
|
|
};
|
||
|
|
}
|
||
|
|
}
|
||
|
|
exports.Format = Format;
|
||
|
|
/**
|
||
|
|
* Fact chunk; chunk-id is "fact"
|
||
|
|
* http://www-mmsp.ece.mcgill.ca/Documents/AudioFormats/WAVE/WAVE.html
|
||
|
|
* http://www.recordingblogs.com/wiki/fact-chunk-of-a-wave-file
|
||
|
|
*/
|
||
|
|
class FactChunk {
|
||
|
|
constructor(header) {
|
||
|
|
if (header.chunkSize < 4) {
|
||
|
|
throw new Error('Invalid fact chunk size.');
|
||
|
|
}
|
||
|
|
this.len = header.chunkSize;
|
||
|
|
}
|
||
|
|
get(buf, off) {
|
||
|
|
return {
|
||
|
|
dwSampleLength: buf.readUInt32LE(off)
|
||
|
|
};
|
||
|
|
}
|
||
|
|
}
|
||
|
|
exports.FactChunk = FactChunk;
|