[BUG] - recordVideo produces corrupted files
**Describe the bug**
When trying to initiate recordVideo, the resulting video is corrupted.  The top part of the stream (where the OSD is) is fine but the rest is corrupted/empty artifacts.

**Expected behavior**
Expecting an uncorrupted frame/video

**Config**
		{
            "platform": "Dafang",
            "mqtt": {
                "hostBroker": true,
				"port": 1883,
				"host": "homebridgeIP",
                "debug": true,
                "mongoUrl": "mongodb://homebridgeIP:27017/mqtt"
            },
            "cameras": [{
                "cameraName": "PanCam",
                "cameraRTSPStreamUrl": "rtsp://IP:8554/unicast",
                "mqttTopic": "home/pancam/#",
                "folder": "/tmp/",
                "segmentLength": 60,
                "maxDirSize": 32768,
                "checkStorageSizeInterval": 14400,
				"recordingDirectoryPathFormat": "YYYYMMDD",
				"recordingFilenameFormat": "YYYYMMDD-hhmmss",
                "accessories": [
                                    {
                                        "name": "Motion Sensor",
                                        "type": "richMotionSensor",
                                        "threshold": 300000
                                    },
                                    {
                                        "name": "Auto Motion Tracking Switch",
                                        "type": "autoMotionTrackingSwitch"
                                    },
                                    {
                                        "name": "Night Vision Sensor",
                                        "type": "nightVisionSensor",
                                        "threshold": 0
                                    },
                                    {
                                        "name": "Night Vision Switch",
                                        "type": "nightVisionSwitch"
                                    },
                                    {
                                        "name": "Auto Night Vision Switch",
                                        "type": "autoNightVisionSwitch"
                                    },
                                    {
                                        "name": "Horizontal Left",
                                        "type": "moveCamera",
                                        "axis": "horizontal",
                                        "direction": "left"
                                    },
                                    {
                                        "name": "Horizontal Right",
                                        "type": "moveCamera",
                                        "axis": "horizontal",
                                        "direction": "right"
                                    },
                                    {
                                        "name": "Vertical Up",
                                        "type": "moveCamera",
                                        "axis": "vertical",
                                        "direction": "up"
                                    },
                                    {
                                        "name": "Vertical Down",
                                        "type": "moveCamera",
                                        "axis": "vertical",
                                        "direction": "down"
                                    },
                                    {
                                        "name": "Record Video",
                                        "type": "recordVideo"
                                    },
                                    {
                                        "name": "Record Audio",
                                        "type": "recordAudio"
                                    },
                                    {
                                        "name": "Capture Image",
                                        "type": "captureImage"
                                    },
                                    {
                                        "name": "RPi Storage Sensor",
                                        "type": "storageSensor"
                                    },
                                    {
                                        "name": "Reset Streaming",
                                        "type": "resetFFMPEG"
                                    },
                                    {
                                        "name": "Motion Detection Switch",
                                        "type": "motionDetection"
                                    },
                                    {
                                        "name": "Restart Switch",
                                        "type": "restartSwitch"
                                    },
                                    {
                                        "name": "Recalibrate Switch",
                                        "type": "recalibrateSwitch"
                                    },
                                    {
                                        "name": "Camera Brightness",
                                        "type": "brightness"
                                    }
                    ],
                    "videoConfig": {
                        "source": "-rtsp_transport tcp -i rtsp://IP:8554/unicast",
                        "stillImageSource": "-rtsp_transport tcp -i rtsp://IP:8554/unicast -vframes 1 -r 1",
						"maxStreams": 2,
                        "maxWidth": 1280,
                        "maxHeight": 720,
                        "maxFPS": 25,
						"maxBitrate": 128,
						"packetSize": 188,
						"debug": true


**Logs**
N/A

**Screenshots**
N/A

**Desktop (please complete the following information):**
 - OS: ubuntu  4.13.0-46-generic #51-Ubuntu SMP Tue Jun 12 12:36:29 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
 - Node Version 11.6

**Additional context**
I actually figured out what the issue is.

when recordVideo calls: 

ffmpeg -i rtsp://IP:8554/unicast -acodec copy -vcodec copy [file] 

It should add -rtsp_transport tcp argument to the command line.

ffmpeg -rtsp_transport tcp -i -i rtsp://IP:8554/unicast -acodec copy -vcodec copy [file] 

I can reproduce the corrupted video with the first line but the second command does not produce a corrupted video. 

Thanks!