Homebridge use homebridge-camera-ffmpeg to link MotionEye mjpeg camera stream
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**Describe The Problem:**

I have tow raspberry pi: (A) Raspberry pi 4B,(B)Raspberry pi zero W. 

(A) Raspberry pi 4B is as a agent to connect mjpeg camera(Raspberry pi zero W) and Homekit. I Install plugin homebridge-camera-ffmpeg and made the configuration according to the following example(https://sunoo.github.io/homebridge-camera-ffmpeg/configs/MotionEyeOS.html). But in the Home App, the camera(Raspberry pi zero W) show no picture.


(A) Raspberry pi 4B

Raspbian-Homebridge-v1.0.21 (https://github.com/homebridge/homebridge-raspbian-image/releases/tag/v1.0.21)

**Environment:**

System Information
Timezone	GMT+0800
OS		Raspbian GNU/Linux Buster (10)
Hostname	homebridge
IPv4 (eth0) 	192.168.1.110
Timezone	fe80::dc82:4804:447:7e28
Node.js Version	v14.16.0
Npm Version	v7.6.3
User		pi
Storage Path	/var/lib/homebridge
Config Path	/var/lib/homebridge/config.json
Service Mode	Yes

**Homebridge Config:**:

```
{
    "bridge": {
        "name": "Homebridge BFA9",
        "username": "0E:2D:58:50:2C:BD",
        "port": 51430,
        "pin": "666-66-666",
        "bind": [
            "eth0"
        ],
        "advertiser": "bonjour-hap"
    },
    "accessories": [],
    "platforms": [
        {
            "name": "Config",
            "port": 8581,
            "auth": "form",
            "theme": "auto",
            "tempUnits": "c",
            "lang": "en",
            "platform": "config"
        },
        {
            "name": "Camera FFmpeg",
            "videoProcessor": "/usr/bin/ffmpeg",
            "cameras": [
                {
                    "name": "MotionEyeOS",
                    "manufacturer": "RPi",
                    "model": "ABC-123",
                    "serialNumber": "1234567890",
                    "firmwareRevision": "1.0",
                    "motion": false,
                    "unbridge": false,
                    "videoConfig": {
                        "source": "-re -i http://192.168.1.102:8081",
                        "maxStreams": 2,
                        "maxWidth": 640,
                        "maxHeight": 480,
                        "maxFPS": 10,
                        "audio": false,
                        "debug": true
                    }
                }
            ],
            "platform": "Camera-ffmpeg"
        }
    ]
}
```

(B) Raspberry pi zero W

motionEye Version 	0.42
Motion Version 		4.2.2
OS Version 		Raspbian 10

motionEye in the Raspberry pi zero W works well, I can show picture in the firefox.


There is no error in the logs, but I cannot view the camera stream in my Home App.

**Logs:** in the Raspberry pi 4B:

```
[08/04/2021, 14:29:48] [Homebridge UI] Homebridge Config UI X v4.41.0 is listening on :: port 8581
[08/04/2021, 14:29:48] [HB Supervisor] Starting Homebridge with extra flags: -I -D
[08/04/2021, 14:29:49] [HB Supervisor] Started Homebridge v1.3.4 with PID: 10673
Initializing HAP-NodeJS v0.9.4...
[08/04/2021, 14:29:50] Loaded config.json with 0 accessories and 2 platforms.
[08/04/2021, 14:29:50] Loaded 0 cached accessories from cachedAccessories.
[08/04/2021, 14:29:50] ---
[08/04/2021, 14:29:51] Loaded plugin: homebridge-camera-ffmpeg@3.1.2
[08/04/2021, 14:29:51] Registering platform 'homebridge-camera-ffmpeg.Camera-ffmpeg'
[08/04/2021, 14:29:51] ---
[08/04/2021, 14:29:51] Loaded plugin: homebridge-config-ui-x@4.41.0
[08/04/2021, 14:29:51] Registering platform 'homebridge-config-ui-x.config'
[08/04/2021, 14:29:51] ---
[08/04/2021, 14:29:51] Loading 2 platforms...
[08/04/2021, 14:29:51] [Config] Initializing config platform...
[08/04/2021, 14:29:51] [Config] Running in Service Mode
[08/04/2021, 14:29:51] [Camera FFmpeg] Initializing Camera-ffmpeg platform...
[08/04/2021, 14:29:51] [Camera FFmpeg] Initializing child bridge 0E:DA:73:34:86:8C
Preparing Advertiser for 'Homebridge BFA9 E0EF' using bonjour-hap backend!
Setup Payload:
X-HM://0024KMGFELGAV
Enter this code with your HomeKit app on your iOS device to pair with Homebridge:
                       
    ┌────────────┐     
    │ 666-66-666 │     
    └────────────┘     
                       
Starting to advertise 'Homebridge BFA9 E0EF' using bonjour-hap backend!
[08/04/2021, 14:29:51] Homebridge v1.3.4 (Homebridge BFA9) is running on port 51430.
Initializing HAP-NodeJS v0.9.4...
[08/04/2021, 14:29:52] [Camera FFmpeg] Launched child bridge with PID 10807
[08/04/2021, 14:29:52] Registering platform 'homebridge-camera-ffmpeg.Camera-ffmpeg'
[08/04/2021, 14:29:52] [Camera FFmpeg] Loaded homebridge-camera-ffmpeg v3.1.2 child bridge successfully
[08/04/2021, 14:29:52] Loaded 0 cached accessories from cachedAccessories.0EDA7334868C.
Preparing Advertiser for 'Camera FFmpeg 3CED' using bonjour-hap backend!
[08/04/2021, 14:29:52] [Camera FFmpeg] [MotionEyeOS] Configuring unbridged accessory...
Starting to advertise 'Camera FFmpeg 3CED' using bonjour-hap backend!
[08/04/2021, 14:29:52] Homebridge v1.3.4 (Camera FFmpeg) is running on port 55722.
Preparing Advertiser for 'MotionEyeOS CD9E' using bonjour-hap backend!
Starting to advertise 'MotionEyeOS CD9E' using bonjour-hap backend!
[08/04/2021, 14:29:52] MotionEyeOS CD9E is running on port 38083.
[08/04/2021, 14:29:52] Please add [MotionEyeOS CD9E] manually in Home app. Setup Code: 666-66-666
[08/04/2021, 14:39:53] [Homebridge UI] Changes to config.json saved.
[08/04/2021, 14:40:09] [Homebridge UI] Changes to config.json saved.
[08/04/2021, 14:40:11] [Homebridge UI] Homebridge restart request received
[08/04/2021, 14:40:12] [Homebridge UI] No restart command defined, killing process...
[08/04/2021, 14:40:12] [HB Supervisor] Stopping services...
[08/04/2021, 14:40:12] Got SIGTERM, shutting down Homebridge...
[08/04/2021, 14:40:12] Got SIGTERM, shutting down child bridge process...
[08/04/2021, 14:40:17] [HB Supervisor] Homebridge Process Ended. Code: 143, Signal: null
[08/04/2021, 14:40:24] [HB Supervisor] OS: Linux 5.10.17-v7l+ arm
[08/04/2021, 14:40:24] [HB Supervisor] Node.js v14.16.0 /usr/local/bin/node
[08/04/2021, 14:40:24] [HB Supervisor] Homebridge Path: /usr/local/lib/node_modules/homebridge/bin/homebridge
[08/04/2021, 14:40:24] [HB Supervisor] UI Path: /usr/local/lib/node_modules/homebridge-config-ui-x/dist/bin/standalone.js
[08/04/2021, 14:40:28] [Homebridge UI] Homebridge Config UI X v4.41.0 is listening on :: port 8581
[08/04/2021, 14:40:28] [HB Supervisor] Starting Homebridge with extra flags: -I -D -K
[08/04/2021, 14:40:28] [HB Supervisor] Started Homebridge v1.3.4 with PID: 11000
Initializing HAP-NodeJS v0.9.4...
[08/04/2021, 14:40:29] Loaded config.json with 0 accessories and 2 platforms.
[08/04/2021, 14:40:29] Loaded 0 cached accessories from cachedAccessories.
[08/04/2021, 14:40:29] ---
[08/04/2021, 14:40:30] Loaded plugin: homebridge-camera-ffmpeg@3.1.2
[08/04/2021, 14:40:30] Registering platform 'homebridge-camera-ffmpeg.Camera-ffmpeg'
[08/04/2021, 14:40:30] ---
[08/04/2021, 14:40:30] Loaded plugin: homebridge-config-ui-x@4.41.0
[08/04/2021, 14:40:30] Registering platform 'homebridge-config-ui-x.config'
[08/04/2021, 14:40:30] ---
[08/04/2021, 14:40:30] Loading 2 platforms...
[08/04/2021, 14:40:30] [Config] Initializing config platform...
[08/04/2021, 14:40:30] [Config] Running in Service Mode
[08/04/2021, 14:40:30] [Camera FFmpeg] Initializing Camera-ffmpeg platform...
[08/04/2021, 14:40:30] [Camera FFmpeg] [MotionEyeOS] Configuring bridged accessory...
Preparing Advertiser for 'Homebridge BFA9 E0EF' using bonjour-hap backend!
Setup Payload:
X-HM://0024KMGFELGAV
Enter this code with your HomeKit app on your iOS device to pair with Homebridge:
                       
    ┌────────────┐     
    │ 666-66-666 │     
    └────────────┘     
                       
Starting to advertise 'Homebridge BFA9 E0EF' using bonjour-hap backend!
[08/04/2021, 14:40:30] Homebridge v1.3.4 (Homebridge BFA9) is running on port 51430.
[08/04/2021, 14:43:14] [Camera FFmpeg] [MotionEyeOS] Identify requested.
[08/04/2021, 14:44:34] [Homebridge UI] Starting terminal session

```
