我有一个 Blazor 托管应用程序,我需要根据客户请求从 AXIS 摄像机获取 h264 录制内容(通过 RTSP PLAY 命令)并以浏览器可以重现视频的方式返回它。如果向 AXIS 摄像机查询录音列表,答案包括这个,即我尝试在浏览器上播放的那个
<recording diskid="SD_DISK" recordingid="20211109_122753_1AB3_B8A44F2D0300" starttime="2021-11-09T11:27:53.060281Z" starttimelocal="2021-11-09T12:27:53.060281+01:00" stoptime="2021-11-09T11:43:01.125987Z" stoptimelocal="2021-11-09T12:43:01.125987+01:00" recordingtype="continuous" eventid="continuous" eventtrigger="continuous" recordingstatus="completed" source="1" locked="No">
<video mimetype="video/x-h264" width="800" height="600" framerate="15:1" resolution="800x600"/>
</recording>
我可以通过“开放网络流...”并输入来成功地使用 VLC 重现录音
rtsp://192.168.0.125/axis-media/media.amp?recordingid=20211109_140710_E1A3_B8A44F2D0300
然后提供用户名和密码,所以我确信命令是正确的。通过在 url 中嵌入用户名和密码,可以播放录音this项目也是如此,其中使用了我在下面使用的更简单的语法,因此我的示例可能有点过于复杂。
服务器端我可以成功检索流,这要归功于RtspClientSharp,但我无法以正确的方式返回它。到目前为止我有这个:
[HttpGet("RecordingsDemo")]
public async Task<IActionResult> RecordingsDemo() {
string deviceIp = "rtsp://192.168.0.125";
string recordingUri = "rtsp://192.168.0.125/axis-media/media.amp?recordingid=20211109_140710_E1A3_B8A44F2D0300";
Uri playRequestUri = new Uri(recordingUri);
CancellationTokenSource cts = new CancellationTokenSource();
NetworkCredential networkCredential = new NetworkCredential("user", "password");
ConnectionParameters connectionParameters = new ConnectionParameters(new Uri(deviceIp), networkCredential);
RtspTcpTransportClient RtspTcpClient = new RtspTcpTransportClient(connectionParameters);
await RtspTcpClient.ConnectAsync(cts.Token);
RtspRequestMessage message = new RtspRequestMessage(RtspMethod.SETUP, playRequestUri);
message.AddHeader("Transport", "RTP/AVP/TCP;unicast");
RtspResponseMessage response = await RtspTcpClient.EnsureExecuteRequest(message, cts.Token);
System.Collections.Specialized.NameValueCollection headers = response.Headers;
string sessionId = headers["SESSION"];
if (sessionId == null) { throw new Exception("RTSP initialization failed: no session id returned from SETUP command"); }
message = new RtspRequestMessage(RtspMethod.PLAY, playRequestUri, sessionId);
response = await RtspTcpClient.EnsureExecuteRequest(message, cts.Token);
Stream stream = RtspTcpClient.GetStream();
if (stream != null) {
Response.Headers.Add("Cache-Control", "no-cache");
FileStreamResult result = new FileStreamResult(stream, "video/x-h264") {
EnableRangeProcessing = true
};
return result;
} else {
return new StatusCodeResult((int)HttpStatusCode.ServiceUnavailable);
}
return new StatusCodeResult((int)HttpStatusCode.OK);
}
请注意,在上面的代码中,我向 RtspRequestMessage 添加了一个构造函数,以便更快地构建它。特别是我添加了以下代码:
public uint _lastCSeqUsed { get; private set; }
/// <param name="method">SETUP, PLAY etc</param>
/// <param name="connectionUri">rtsp://<servername>/axis-media/media.amp?recordingid=...</param>
/// <param name="cSeq">Method that generate the sequence number. The receiver will reply with the same sequence number</param>
/// <param name="protocolVersion">Default to 1.0 if omitted or null</param>
/// <param name="userAgent">Doesn't matter really</param>
/// <param name="session">This parameter has to be initialized with the value returned by the SETUP method</param>
public RtspRequestMessage(RtspMethod method, Uri connectionUri, string session = "", Func<uint> cSeqProvider = null,
Version protocolVersion = null, string userAgent = "client")
: base((protocolVersion != null) ? protocolVersion : new Version("1.0"))
{
Method = method;
ConnectionUri = connectionUri;
UserAgent = userAgent;
_cSeqProvider = (cSeqProvider != null) ? cSeqProvider : myfun;
CSeq = (cSeqProvider != null) ? _cSeqProvider() : 0;
if (!string.IsNullOrEmpty(session))
Headers.Add("Session", session);
}
public void AddHeader(string name, string value)
{
Headers.Add(name, value);
}
private uint myfun()
{
return ++CSeq;
}
当客户端通过 GET 方法调用此方法时,我非常确定通过查看 bandwitdh 和 Wireshark 可以正确检索记录。您可以在下图中看到 Wireshark 输出,其中 192.168.0.125 是摄像头,192.168.0.120 是服务器。
但是服务器返回的文件似乎无法播放。即使使用 VLC,我也无法播放返回的文件或流。
客户端与服务器的通信如下图所示,其中192.168.0.16是客户端,192.168.0.51是服务器。
我需要能够返回 html5 视频元素可以播放的流。
你能指出我正确的方向吗?谢谢
EDIT.:正如你所看到的,我找到了一种方法,发布在下面。不过,我希望有一个更好的解决方案,不需要在磁盘上写入,也不会因生成 .ts 文件而增加延迟。因此,我对是否有人愿意做出贡献的问题保持开放。