问题描述
我正在尝试使用FFMPEG在NodeJS服务器中由MediaRecorderAPI生成的blob创建一个webm视频文件。我可以创建 .webm 文件，但是无法播放，我运行了该命令$ ffmpeg.exe -v error -i lel.webm -f null - >error.log 2>&1 来生成错误日志，该错误日志文件包含以下内容：
[null @ 000002ce7501de40]应用程序向流0：1中的复用器提供了无效且非单调递增的dts
[h264 @ 000002ce74a727c0]无效的NAL单位大小（804> 74）。
[h264 @ 000002ce74a727c0]将输入拆分为NAL单元时出错。
解码流＃0：0时出错：处理输入时发现无效数据
这是我的Web服务器代码
const app = require("express")();
const http = require("http").createServer(app);
const io = require("socket.io")(http);
const fs = require("fs");
const child_process = require("child_process");
app.get("/",(req,res) => {
res.sendFile(__dirname + "/index.html");
});
io.on("connection",(socket) => {
console.log("a user connected");
const ffmpeg = child_process.spawn("ffmpeg",[
"-i","-","-vcodec","copy","-f","flv","rtmpurl.webm",]);
ffmpeg.on("close",(code,signal) => {
console.log(
"FFmpeg child process closed,code " + code + ",signal " + signal
);
});
ffmpeg.stdin.on("error",(e) => {
console.log("FFmpeg STDIN Error",e);
});
ffmpeg.stderr.on("data",(data) => {
console.log("FFmpeg STDERR:",data.toString());
});
socket.on("message",(msg) => {
console.log("Writing blob! ");
ffmpeg.stdin.write(msg);
});
socket.on("stop",() => {
console.log("Stop recording..");
ffmpeg.kill("SIGINT");
});
});
http.listen(3000,() => {
console.log("listening on *:3000");
});
这是我的客户端代码，使用HTML，JS：
<!DOCTYPE html>
<html lang="en">
<head>
<Meta charset="UTF-8" />
<Meta name="viewport" content="width=device-width,initial-scale=1.0" />
<title>Document</title>
</head>
<script src="/socket.io/socket.io.js"></script>
<script>
const socket = io();
let mediaRecorder = null;
const startRecording = (someStream) => {
const mediaStream = new MediaStream();
const videoTrack = someStream.getVideoTracks()[0];
const audioTrack = someStream.getAudioTracks()[0];
console.log("Video trac ",videoTrack);
console.log("audio trac ",audioTrack);
mediaStream.addTrack(videoTrack);
mediaStream.addTrack(audioTrack);
const recorderOptions = {
mimeType: "video/webm;codecs=h264",videoBitsPerSecond: 3 * 1024 * 1024,};
mediaRecorder = new MediaRecorder(mediaStream,recorderOptions);
mediaRecorder.start(1000); // 1000 - the number of milliseconds to record into each Blob
mediaRecorder.ondataavailable = (event) => {
console.debug("Got blob data:",event.data);
if (event.data && event.data.size > 0) {
socket.emit("message",event.data);
}
};
};
const getVideoStream = async () => {
try {
const stream = await navigator.mediaDevices.getUserMedia({
video: true,audio: true,});
startRecording(stream);
myVideo.srcObject = stream;
} catch (e) {
console.error("navigator.getUserMedia error:",e);
}
};
const stopRecording = () => {
mediaRecorder.stop();
socket.emit("stop");
};
</script>
<body>
<p>hello world</p>
<button onclick="getVideoStream()">start rec</button>
<button onclick="stopRecording()">stop rec</button>
<video width="300" height="300" autoplay id="myvideo" />
<script>
const myVideo = document.getElementById("myvideo");
myVideo.muted = true;
</script>
</body>
</html>
感谢您的帮助！
解决方法
看起来您正在编码为flv，而不是webm。因此，您已经在webm容器中进行了flv编码的视频-播放设备根本不知道该怎么处理：）
仅在计算机上的mp4上尝试上述命令-我敢打赌，它将无法正常工作。要编码为webm，请检查以下ffmpeg commands