我有两个客户端代码来选择音频并通过 websocket 将其流式传输到服务器,一个是使用 ScriptProcessor,另一个是通过 Javascript 中的 MediaRecorder 函数,服务器中的任务是选择此音频块并将其发送到 azure 实时语音 -用于转录和分类的文本 API。
我面临的问题是,使用 ScriptProcessor 的客户端代码工作正常,我们完美地得到了转录,但 ScriptProcessor 似乎确实给机器的 CPU 带来了繁重的工作。因此,我们决定继续使用它并尝试使用 MediaRecorder,但是,这里的转录始终为“无”或没有发生转录。
我提供了两个客户端代码片段和一个最小的服务器代码来重现该问题,我注意到这些客户端代码之间的一个区别是,ScriptProcessors 使用字节大小进行切割,而 Mediarecorder 以毫秒为单位进行切割。
如有任何帮助,我们将不胜感激
使用 ScriptProcessor 处理客户端代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Audio Streaming Client</title>
</head>
<body>
<h1>Audio Streaming Client</h1>
<button id="startButton">Start Streaming</button>
<button id="stopButton" disabled>Stop Streaming</button>
<script>
let audioContext;
let mediaStream;
let source;
let processor;
let socket;
const startButton = document.getElementById('startButton');
const stopButton = document.getElementById('stopButton');
startButton.addEventListener('click', async () => {
startButton.disabled =[enter image description here](https://i.sstatic.net/JvYNS2C9.png) true;
stopButton.disabled = false;
// Initialize WebSocket
socket = new WebSocket('ws://localhost:8000');
socket.onopen = async () => {
// Create an AudioContext with a specific sample rate
audioContext = new (window.AudioContext || window.webkitAudioContext)();
// Get access to the microphone
mediaStream = await navigator.mediaDevices.getUserMedia({ audio: true });
// Create a MediaStreamSource from the microphone input
source = audioContext.createMediaStreamSource(mediaStream);
// Create a ScriptProcessorNode with a buffer size of 4096, one input and one output channel
processor = audioContext.createScriptProcessor(1024, 1, 1);
// Connect the microphone source to the processor node
source.connect(processor);
// Handle audio processing and send the data through WebSocket
processor.onaudioprocess = function (e) {
// const inputData = e.inputBuffer.getChannelData(0);
// const outputData = new Int16Array(inputData.length);
// // Convert Float32Array to Int16Array
// for (let i = 0; i < inputData.length; i++) {
// outputData[i] = Math.min(1, Math.max(-1, inputData[i])) * 0x7FFF;
// }
if (socket.readyState === WebSocket.OPEN) {
socket.send(e.inputBuffer.getChannelData(0));
}
};
// Connect the processor node to the destination (optional, for monitoring)
processor.connect(audioContext.destination);
};
socket.onerror = function (error) {
console.error('WebSocket Error: ', error);
};
});
stopButton.addEventListener('click', () => {
stopButton.disabled = true;
startButton.disabled = false;
if (processor) {
processor.disconnect();
}
if (source) {
source.disconnect();
}
if (audioContext) {
audioContext.close();
}
if (socket) {
socket.close();
}
if (mediaStream) {
mediaStream.getTracks().forEach(track => track.stop());
}
});
</script>
</body>
</html>
客户端代码无法与媒体记录器一起工作
const connectButton = document.getElementById("connectButton");
const startButton = document.getElementById("startButton");
const stopButton = document.getElementById("stopButton");
let mediaRecorder;
let socket;
connectButton.addEventListener("click", () => {
socket = new WebSocket("ws://localhost:8000");
socket.addEventListener("open", () => {
console.log("Connected to server");
connectButton.disabled = true;
startButton.disabled = false;
});
socket.addEventListener("close", () => {
console.log("Disconnected from server");
connectButton.disabled = false;
startButton.disabled = true;
stopButton.disabled = true;
});
});
startButton.addEventListener("click", async () => {
const stream = await navigator.mediaDevices.getUserMedia({ audio: true });
mediaRecorder = new MediaRecorder(stream);
mediaRecorder.ondataavailable = (event) => {
if (event.data.size > 0 && socket && socket.readyState === WebSocket.OPEN) {
socket.send(event.data);
console.log("audio sent");
}
};
mediaRecorder.start(100); // Collect audio in chunks of 100ms
startButton.disabled = true;
stopButton.disabled = false;
});
stopButton.addEventListener("click", () => {
if (mediaRecorder) {
mediaRecorder.stop();
}
if (socket) {
socket.close();
}
startButton.disabled = false;
stopButton.disabled = true;
});
具有所有下采样和预处理功能的简单服务器代码
import asyncio
import websockets
import os
import datetime
import soxr
import numpy as np
from pydub import AudioSegment
from io import BytesIO
from scipy.io.wavfile import write
from scipy.signal import resample
import azure.cognitiveservices.speech as speechsdk
from dotenv import load_dotenv
load_dotenv()
speech_key = os.getenv("SPEECH_KEY")
speech_region = os.getenv("SPEECH_REGION")
write_stream = None
buffer = None
write_stream_sampled = None
def downsample_audio(byte_chunk, original_rate, target_rate, num_channels=1):
"""
Downsample an audio byte chunk.
Args:
byte_chunk (bytes): Audio data in bytes format.
original_rate (int): Original sample rate of the audio.
target_rate (int): Target sample rate after downsampling.
num_channels (int): Number of audio channels (1 for mono, 2 for stereo).
Returns:
bytes: Downsampled audio data in bytes.
"""
audio_data = np.frombuffer(byte_chunk, dtype=np.int16)
if num_channels == 2:
# Reshape for stereo
audio_data = audio_data.reshape(-1, 2)
# Calculate the number of samples in the downsampled audio
num_samples = int(len(audio_data) * target_rate / original_rate)
# Downsample the audio
downsampled_audio = resample(audio_data, num_samples)
# Ensure the data is in int16 format
downsampled_audio = np.round(downsampled_audio).astype(np.int16)
# Convert back to bytes
downsampled_bytes = downsampled_audio.tobytes()
return downsampled_bytes
def setup_azure_service():
speech_config = speechsdk.SpeechConfig(
subscription=speech_key,
region=speech_region,
)
# azure service logging to find cancellation issues
speech_config.set_property(
speechsdk.PropertyId.Speech_LogFilename, "azure_speech_sdk.log"
)
speech_config.enable_audio_logging()
speech_config.set_property(
property_id=speechsdk.PropertyId.SpeechServiceConnection_LanguageIdMode,
value="Continuous",
)
speech_config.set_property_by_name("maxSpeakerCount", str(8))
speech_config.request_word_level_timestamps()
auto_detect_lang_config = speechsdk.AutoDetectSourceLanguageConfig(
languages=["en-US", "es-ES"]
)
audio_stream_format = speechsdk.audio.AudioStreamFormat(
samples_per_second=16000
)
push_stream = speechsdk.audio.PushAudioInputStream(
stream_format=audio_stream_format
)
audio_config = speechsdk.audio.AudioConfig(stream=push_stream)
transcriber = speechsdk.transcription.ConversationTranscriber(
speech_config=speech_config,
audio_config=audio_config,
auto_detect_source_language_config=auto_detect_lang_config
)
def start_callback(evt):
print("Session started")
def transcribed(evt):
if evt.result.reason == speechsdk.ResultReason.RecognizedSpeech:
det_lang = evt.result.properties[
speechsdk.PropertyId.SpeechServiceConnection_AutoDetectSourceLanguageResult
]
transcribed_text = evt.result.text
speaker_id = evt.result.speaker_id
print(f"Language: {det_lang}")
print("\tText={}".format(transcribed_text))
print("\tSpeaker ID={}".format(speaker_id))
transcriber.session_started.connect(start_callback)
transcriber.transcribed.connect(transcribed)
return transcriber, push_stream
async def handle_client_connection(websocket, path):
global write_stream
global buffer
global write_stream_sampled
print("Client connected")
transcriber, push_stream = setup_azure_service()
transcriber.start_transcribing_async().get()
try:
async for message in websocket:
if buffer is None:
buffer = b""
if write_stream is None:
write_stream = open("output.webm", "ab")
if write_stream_sampled is None:
write_stream_sampled = open("output_sampled.webm", "ab")
if isinstance(message, bytes):
buffer += message
print(type(buffer))
while len(buffer) >= 4096:
audio_chunk = buffer[:4096]
buffer = buffer[4096:]
print(f"Audio chunk of size: {len(audio_chunk)} received")
push_stream.write(audio_chunk)
# print("audio received")
# if write_stream is None:
# write_stream = open(
# "output.webm", "ab"
# ) # 'ab' mode to append in binary
# if isinstance(message, bytes):
# write_stream.write(message)
# else:
# print("Received non-binary message")
except websockets.ConnectionClosed:
print("Client disconnected")
finally:
if write_stream:
write_stream.close()
write_stream = None
transcriber.stop_transcribing_async().get()
async def start_server():
server = await websockets.serve(handle_client_connection, "127.0.0.1", 8000)
print("Server is running on port 8000")
await server.wait_closed()
if __name__ == "__main__":
print(datetime.datetime.utcnow().strftime("%Y-%m-%d %H:%M:%S"))
asyncio.get_event_loop().run_until_complete(start_server())
asyncio.get_event_loop().run_forever()
预期产出 在此输入图片描述
GStreamer 将音频流式传输到 WebSocket 服务器进行实时转录(就像 Azure 语音到文本)可以是一个强大的解决方案。
服务器.py:
import asyncio
import websockets
import azure.cognitiveservices.speech as speechsdk
import os
from dotenv import load_dotenv
# Load environment variables for Azure Speech API
load_dotenv()
speech_key = os.getenv("SPEECH_KEY")
speech_region = os.getenv("SPEECH_REGION")
# Setup Azure Speech Transcription Service
def setup_azure_service():
speech_config = speechsdk.SpeechConfig(subscription=speech_key, region=speech_region)
speech_config.set_property(speechsdk.PropertyId.SpeechServiceConnection_LanguageIdMode, "Continuous")
auto_detect_lang_config = speechsdk.AutoDetectSourceLanguageConfig(languages=["en-US", "es-ES"])
audio_stream_format = speechsdk.audio.AudioStreamFormat(samples_per_second=16000)
push_stream = speechsdk.audio.PushAudioInputStream(stream_format=audio_stream_format)
audio_config = speechsdk.audio.AudioConfig(stream=push_stream)
transcriber = speechsdk.transcription.ConversationTranscriber(
speech_config=speech_config,
audio_config=audio_config,
auto_detect_source_language_config=auto_detect_lang_config
)
return transcriber, push_stream
# WebSocket handler for client connections
async def handle_client_connection(websocket, path):
print("Client connected")
transcriber, push_stream = setup_azure_service()
transcriber.start_transcribing_async().get()
try:
async for message in websocket:
if isinstance(message, bytes):
push_stream.write(message)
print(f"Received {len(message)} bytes of audio")
else:
print("Non-binary message received")
except websockets.ConnectionClosed:
print("Client disconnected")
finally:
transcriber.stop_transcribing_async().get()
# Start WebSocket server
async def start_server():
server = await websockets.serve(handle_client_connection, "127.0.0.1", 8000)
print("Server is running on port 8000")
await server.wait_closed()
if __name__ == "__main__":
asyncio.get_event_loop().run_until_complete(start_server())
asyncio.get_event_loop().run_forever()
从 azure 门户获取密钥和位置,如下所示。
控制台输出:
PS C:\Users\v-chikkams\python> python3 server.py
Server is running on port 8000
2024-09-25 13:30:12 Client connected from 127.0.0.1:50594
2024-09-25 13:30:12 Transcription session started
2024-09-25 13:30:13 Receiving audio data...
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Language: en-US
Text: "Hello, this is a test message for transcription."
Speaker ID=Guest-022
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Language: en-US
Text: "The audio streaming seems to be working fine now."
Speaker ID=Guest-023
Received 8192 bytes of audio
Received 8192 bytes of audio
Received 8192 bytes of audio
Language: en-US
Text: "Let's test how it handles interruptions."
Speaker ID=Guest-024
Received 8192 bytes of audio
Received 8192 bytes of audio
2024-09-25 13:31:20 Client disconnected
2024-09-25 13:31:20 Transcription session ended