From b1e257df9671d2c84110efbb993bd9906441c665 Mon Sep 17 00:00:00 2001 From: yuchiXiong Date: Sat, 4 Mar 2023 14:39:21 +0800 Subject: [PATCH] =?UTF-8?q?feat:=20=E5=B0=9D=E8=AF=95=E4=BD=BF=E7=94=A8=20?= =?UTF-8?q?Web=20Audio=20API=20=E6=9B=BF=E6=8D=A2=20FFmpeg=20=E8=BF=9B?= =?UTF-8?q?=E8=A1=8C=E9=9F=B3=E9=A2=91=E7=9A=84=E8=BD=AC=E7=A0=81?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- lib/internal/contactable.ts | 86 ++++++++++++++++++++++++++++++------- package.json | 1 + 2 files changed, 71 insertions(+), 16 deletions(-) diff --git a/lib/internal/contactable.ts b/lib/internal/contactable.ts index b7fadc3e..ab00d1e3 100644 --- a/lib/internal/contactable.ts +++ b/lib/internal/contactable.ts @@ -5,6 +5,7 @@ import axios from "axios" import { Readable } from "stream" import { pcm2slk } from 'node-silk'; import { randomBytes } from "crypto" +const { AudioContext } = require('web-audio-api') import { exec } from "child_process" import { tea, pb, ApiRejection } from "../core" import { ErrorCode, drop } from "../errors" @@ -310,7 +311,7 @@ export abstract class Contactable { this.c.logger.debug("开始语音任务") if (typeof elem.file === "string" && elem.file.startsWith("protobuf://")) return elem - const buf = await getPttBuffer(elem.file, this.c.config.ffmpeg_path) + const buf = await getPttBuffer(elem.file) const hash = md5(buf) const codec = String(buf.slice(0, 7)).includes("SILK") ? 1 : 0 const body = pb.encode({ @@ -590,7 +591,7 @@ async function* concatStreams(readable1: Readable, readable2: Readable) { yield chunk } -async function getPttBuffer(file: string | Buffer, ffmpeg = "ffmpeg"): Promise { +async function getPttBuffer(file: string | Buffer): Promise { if (file instanceof Buffer || file.startsWith("base64://")) { // Buffer或base64 const buf = file instanceof Buffer ? file : Buffer.from(file.slice(9), "base64") @@ -600,7 +601,7 @@ async function getPttBuffer(file: string | Buffer, ffmpeg = "ffmpeg"): Promise { +function audioTrans(file: string): Promise { return new Promise((resolve, reject) => { - const tmpfile = path.join(TMP_DIR, uuid()) - exec(`${ffmpeg} -i "${file}" -f s16le -ac 1 -ar 24000 "${tmpfile}"`, async (error, stdout, stderr) => { - try { - resolve(pcm2slk(fs.readFileSync(tmpfile))) - } catch { - reject(new ApiRejection(ErrorCode.FFmpegPttTransError, "音频转码到pcm失败，请确认你的ffmpeg可以处理此转换")) - } finally { - fs.unlink(tmpfile, NOOP) - } - }) + const context = new AudioContext(); + + try { + context.decodeAudioData(fs.readFileSync(file), (audioBuffer: AudioBuffer) => { + // 编码参数参考 ffmpeg -i input_path -f s16le -ar 24000 -ac 1 output_path + + const channels = 1; // 单声道 + const rate = 24000; // 采样率为 24000 Hz + + // 更改音频的采样率、声道数和长度 + const newBuffer = context.createBuffer( + channels, + audioBuffer.length * rate / audioBuffer.sampleRate, + rate + ); + + const channelData = newBuffer.getChannelData(0); + const step = audioBuffer.sampleRate / rate; + + for (let i = 0; i < channelData.length; i++) { + const oldIndex = Math.floor(i * step); + channelData[i] = audioBuffer.getChannelData(0)[oldIndex]; + } + + const interleaved = interleave(newBuffer.getChannelData(0)); + const buffer = new ArrayBuffer(interleaved.length * 2); + const view = new DataView(buffer); + + // 将 PCM 数据写入 ArrayBuffer + floatTo16BitPCM(view, 0, interleaved); + + resolve(pcm2slk(Buffer.from(buffer))) + }); + } catch { + reject(new ApiRejection(ErrorCode.FFmpegPttTransError, "音频转码失败，请确认你的音频格式可以被 Web Audio API 处理，详见 https://developer.mozilla.org/zh-CN/docs/Web/API/Web_Audio_API")) + } }) } @@ -649,3 +676,30 @@ async function read7Bytes(file: string) { fd.close() return buf } + + +/** + * @description 将 PCM 数据从 Float32Array 转换为 Int16Array, channel 的类型可参考下方链接 + * @see https://github.com/audiojs/web-audio-api/blob/0ede7359f3b9fdb06108327d6c2838be52d2c63e/src/AudioBuffer.js#L27 + **/ +function interleave(channel: Float32Array) { + const buffer = new ArrayBuffer(channel.length * 2); + const int16Array = new Int16Array(buffer); + + for (let i = 0; i < channel.length; i++) { + const floatValue = channel[i]; + const intValue = Math.max(-1, Math.min(1, floatValue)) * 0x7fff; + int16Array[i] = intValue; + } + + return int16Array; +} + +// 将 PCM 数据从 Int16Array 转换为 S16LE 格式的二进制数据 +function floatTo16BitPCM(output: DataView, offset: number, input: Int16Array) { + for (let i = 0; i < input.length; i++, offset += 2) { + const floatValue = input[i]; + const intValue = Math.max(-0x8000, Math.min(0x7fff, floatValue)); + output.setInt16(offset, intValue, true); + } +} \ No newline at end of file diff --git a/package.json b/package.json index 1b2f5547..f3884714 100644 --- a/package.json +++ b/package.json @@ -30,6 +30,7 @@ "log4js": "^6.3.0", "long": "^4.0.0", "node-silk": "^0.1.0", + "web-audio-api": "^0.2.2", "pngjs": "^6.0.0", "probe-image-size": "^7.2.2" },