FFmpeg process creation failed
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**Describe The Problem:**
After applying the newest Homebridge Docker image as recommended by @oznu , I received an error message in the log saying FFmpeg process creation failed.

**To Reproduce:**
Start the Home app and enter a room with a camera. This will trigger a request for a snapshot picture.

**Logs:**
[6/26/2022, 10:30:55 AM] [Camera-ffmpeg] [Axis hus foran] FFmpeg process creation failed: spawn /homebridge/node_modules/homebridge-camera-ffmpeg/node_modules/ffmpeg-for-homebridge/ffmpeg ENOENT
[Axis hus foran 684A] Snapshot request handler provided empty image buffer!

```
Show the Homebridge logs here.
[6/26/2022, 10:30:55 AM] [Camera-ffmpeg] [Axis hus foran] FFmpeg process creation failed: spawn /homebridge/node_modules/homebridge-camera-ffmpeg/node_modules/ffmpeg-for-homebridge/ffmpeg ENOENT
[Axis hus foran 684A] Snapshot request handler provided empty image buffer!
```

**Homebridge Config:**

           "platform": "Camera-ffmpeg",
            "mqtt": "127.0.0.1",
            "cameras": [
                {
                    "name": "Axis hus foran",
                    "manufacturer": "Axis",
                    "model": "Q3617",
                    "serialNumber": "ACCC8E6E2999",
                    "firmwareRevision": "9.80.3",
                    "unbridge": true,
                    "doorbell": true,
                    "videoConfig": {
                        "source": "-rtsp_transport tcp -i rtsp://---secret---@192.168.1.25:554/axis-media/media.amp?videocodec=h264&streamprofile=Media",
                        "stillImageSource": "-i http://---secret---@192.168.1.25/axis-cgi/jpg/image.cgi",
                        "maxStreams": 3,
                        "maxWidth": 3072,
                        "maxHeight": 1728,
                        "maxFPS": 30,
                        "vcodec": "libx264",
                        "debug": false
                    },
                    "mqtt": {
                        "doorbellTopic": "udenfor/doorbell",
                        "doorbellMessage": "ON"
                    }
                },
                {
                    "name": "Axis hus haven",
                    "manufacturer": "Axis",
                    "model": "M2026-LE Mk II",
                    "serialNumber": "ACCC8ED3AA2D",
                    "firmwareRevision": "9.80.3",
                    "unbridge": true,
                    "videoConfig": {
                        "source": "-rtsp_transport tcp -i rtsp://---secret---@192.168.1.23:554/axis-media/media.amp?videocodec=h264&streamprofile=Media",
                        "stillImageSource": "-i http://---secret---@192.168.1.23/axis-cgi/jpg/image.cgi",
                        "maxStreams": 3,
                        "maxWidth": 1920,
                        "maxHeight": 1080,
                        "maxFPS": 30,
                        "vcodec": "libx264",
                        "debug": false
                    }
                }
            ]

**Screenshots:**
n/a

**Environment:**

* **Node.js Version**:  v16.15.1
* **NPM Version**:  v.3.1.4
* **Homebridge Version**: v1.5.0
* **Homebridge Camera FFmpeg Version**: v3.1.4
* **Homebridge Config UI X Plugin Version**: v4.48.1
* **Operating System**: Ubuntu - running in Docker


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