Unable to find a suitable output format
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**Describe The Problem:**
Hello,

I have an analog DVR that outputs RTSP streams into my local network and a RP3B running homebridge.


I try to add camera with address:

rtsp://10.0.1.22:554/user=admin&password=abc&channel=9.sdp

but there is no stream. Debug log looks like this (first part when I scroll to camera in Home menu in iOS, second is when I tap it):

[2021-4-9 22:47:56] [Camera FFmpeg] [Камера на кухне] [Snapshot] [NULL @ 0x281e420] Unable to find a suitable output format for 'rtsp://10.0.1.22:554/user=admin&password=abc&channel=9.sdp'
[2021-4-9 22:47:56] [Camera FFmpeg] [Камера на кухне] [Snapshot] rtsp://10.0.1.22:554/user=admin&password=abc&channel=9.sdp: Invalid argument
[2021-4-9 22:47:56] [Camera FFmpeg] [Камера на кухне] Failed to fetch snapshot.

[2021-4-9 22:47:58] [Camera FFmpeg] [Камера на кухне] Starting video stream: native x native, native fps, ??? kbps
[2021-4-9 22:47:58] [Camera FFmpeg] [Камера на кухне] [NULL @ 0x29659b0] [error] Unable to find a suitable output format for 'rtsp://10.0.1.22:554/user=admin&password=abc&channel=9.sdp'
[2021-4-9 22:47:58] [Camera FFmpeg] [Камера на кухне] [error] rtsp://10.0.1.22:554/user=admin&password=abc&channel=9.sdp: Invalid argument
[2021-4-9 22:47:58] [Camera FFmpeg] [Камера на кухне] FFmpeg exited with code: 1 and signal: null (Error)
[2021-4-9 22:47:58] [Camera FFmpeg] [Камера на кухне] Stopped video stream.

jsonconfig looks like this:

        {
            "name": "Camera FFmpeg",
            "cameras": [
                {
                    "name": "Камера на кухне",
                    "unbridge": false,
                    "videoConfig": {
                        "source": "rtsp://10.0.1.22:554/user=admin&password=abc&channel=9.sdp",
                        "maxStreams": 1,
                        "maxWidth": 0,
                        "maxHeight": 0,
                        "maxFPS": 0,
                        "vcodec": "copy",
                        "mapvideo": "0"
                    }
                }
            ],
            "platform": "Camera-ffmpeg"
        },

The link itself seems to be allright, when I put it to VLC player it shows me a livestream from the camera. I attach a screenshot with codec info from VLC:

![Снимок](https://user-images.githubusercontent.com/64325270/114234437-6ccde680-9987-11eb-8cbe-0f3d55c92ab9.PNG)

Could the problem maybe be in the h265 codec? Or I miss something else?

Thanks in advance!


**Environment:**

* **Node.js Version**: v12.18.3
* **NPM Version**: v6.14.6
* **Homebridge Version**: v1.3.4
* **Homebridge Camera FFmpeg Version**: v3.1.2
* **Homebridge Config UI X Plugin Version**: v4.41.0
* **Operating System**: Raspbian GNU/Linux Buster (10)
