我正在开展一个项目，需要我：
我当前将从浏览器录制的音频编码为 Base64 字符串（来自由音频块构造的 Blob）：
start() {
return new Promise(resolve => {
navigator.mediaDevices.getUserMedia({ audio: true })
.then(stream => {
this.mediaRecorder = new MediaRecorder(stream);
this.audioChunks = [];
this.mediaRecorder.addEventListener('dataavailable', event => {
this.audioChunks.push(event.data);
});
this.mediaRecorder.start();
});
});
stop() {
this.mediaRecorder.stop();
}
getData() {
const blob = new Blob(this.audioChunks, { type: 'audio/wav;codecs=opus' });
const reader = new FileReader();
reader.readAsDataURL(blob);
reader.onloadend = () => {
const base64data = reader.result;
this.http.post('http://localhost:5000/test', { audio: base64data }).subscribe(res => {
console.log(res);
});
};
}
将其发送到后端后，尝试通过解码 Base64 字符串并使用 Python 'Wave' 包写入文件来保存音频。然而我只是在结果文件中得到静态。
def write_to_file(base64_audio):
decoded = base64.standard_b64decode(base64_audio)
print(type(decoded))
with wave.open('temp/test.wav', 'wb') as wav:
wav.setparams((2, 2, 16000, 0, 'NONE', 'NONE'))
wav.writeframes(decoded)
任何有关如何解决此问题或改进流程的建议将不胜感激。
Python
import base64
import wave
from flask import Flask, request
app = Flask(__name__)
@app.route("/test", methods=["POST"])
def hello():
data = str(request.form)[59:][:-4].replace(" ", "+").encode()
write_to_file(data)
return "Hello World!"
def write_to_file(base64_audio):
import base64
wav_file = open("temp.wav", "wb")
decode_string = base64.b64decode(base64_audio)
wav_file.write(decode_string)
if __name__ == "__main__":
app.run("0.0.0.0", 5000)
HTML
<!DOCTYPE html>
<html>
<head>
<title></title>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.2.2/jquery.min.js"></script>
</head>
<body>
<input type="button" value="start" onclick="start()"></br>
<input type="button" value="stop" onclick="stop()"></br>
<input type="button" value="getData" onclick="getData()"></br>
<script type="text/javascript">
function start() {
return new Promise(resolve => {
navigator.mediaDevices.getUserMedia({audio: true})
.then(stream => {
this.mediaRecorder = new MediaRecorder(stream);
this.audioChunks = [];
this.mediaRecorder.addEventListener('dataavailable', event => {
this.audioChunks.push(event.data);
});
this.mediaRecorder.start();
});
});
}
function stop() {
this.mediaRecorder.stop();
}
function getData() {
let blob = new Blob(this.audioChunks, {type: 'audio/wav;codecs=opus'});
let reader = new FileReader();
reader.readAsDataURL(blob);
reader.onloadend = () => {
let base64data = reader.result;
console.log(base64data)
/*
this.http.post(, {audio: base64data}).subscribe(res => {
console.log(res);
});
*/
$.ajax({
type: "POST",
url: 'http://localhost:5000/test',
data: base64data,
success: function (data) {
alert(data);
}
});
};
}
</script>
</body>
</html>
回答Sreekant的问题，线路
str(request.form)[59:][:-4].replace(" ", "+").encode()
它从表单数据的字符串中删除文本元数据。如果你看一下它，它的开头是这样的：
data:audio/wav;codecs=opus;base64,GkXfo59C
对于我的用例，我这样做了：
str(audiobytes).replace("audio/wav;codecs=opus;base64,", "").encode()