Hikvision DS-7608NI-K2 NVR setup fails
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**Describe The Problem:**
I'm using a Hikvision DS-7608NI-K2 and cannot get it to work even though URLs of video feeds works through VLC and still images are also displayed in the browser. So the URLs are correct. I have used the details such as video dimensions etc from vlc info.

**To Reproduce:**
<!-- Steps to reproduce the behavior. -->

**Logs:**
![image](https://user-images.githubusercontent.com/3821617/190190037-bf6ba604-b4aa-4e74-92e4-d617493b814c.png)

**Config:**

```json
{
    "platform": "Camera-ffmpeg",
    "name": "Camera FFmpeg",
    "cameras": [
        {
            "name": "Hof",
            "manufacturer": "HIK",
            "model": "Camera",
            "serialNumber": "12345678",
            "motion": false,
            "videoConfig": {
                "source": "-re -i rtsp://xxx:xxx@192.168.0.230:554/Streaming/Channels/201",
                "stillImageSource": "-i http://xxx:xxx@192.168.0.230:80/ISAPI/Streaming/channels/201/picture",
                "maxStreams": 2,
                "mapvideo": "201",
                "maxWidth": 2688,
                "maxHeight": 1520,
                "vcodec": "libx264",
                "maxFPS": 25
            },
            "firmwareRevision": "12345678"
        }
    ]
}
```

**Environment:**

* **Node.js Version**: 16.17.0
* **Homebridge Version**: 1.5.0
* **Homebridge Camera FFmpeg Version**:
* **Homebridge Config UI X Plugin Version**:
* **Operating System**: Hoobs 4.2.8 on RPI


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