xsw9527/lpms

Livepeer media server

LPMS - Livepeer media server

LPMS is a media server that can run independently, or on top of the Livepeer network. It allows you to manipulate / broadcast a live video stream. Currently, LPMS supports RTMP as input format and RTMP/HLS as output formats.

LPMS can be integrated into another service, or run as a standalone service. To try LPMS as a standalone service, simply get the package:

go get github.com/livepeer/lpms

Go to the lpms root directory, and run

./lpms

Requirements

LPMS requires ffmpeg. To install it on OSX, use homebrew. As a part of this installation, ffmpeg and ffplay should be installed as commandline utilities.

//This may take a few minutes
brew install ffmpeg --with-sdl2 --with-libx264

Testing out LPMS

The test LPMS server exposes a few different endpoints:

1. rtmp://localhost:1935/stream/test for uploading/viewing RTMP video stream.
2. http://localhost:8000/stream/test_hls.m3u8 for consuming the HLS video stream.

Do the following steps to view a live stream video:

1. Start LPMS by running go run cmd/example/main.go

2. Upload an RTMP video stream to rtmp://localhost:1935/stream/test. We recommend using ffmpeg or OBS.

For ffmpeg on osx, run: ffmpeg -f avfoundation -framerate 30 -pixel_format uyvy422 -i "0:0" -vcodec libx264 -tune zerolatency -b 900k -x264-params keyint=60:min-keyint=60 -f flv rtmp://localhost:1935/stream/test

For OBS, fill in Settings->Stream->URL to be rtmp://localhost:1935

3. If you have successfully uploaded the stream, you should see something like this in the LPMS output

I0324 09:44:14.639405   80673 listener.go:28] RTMP server got upstream
I0324 09:44:14.639429   80673 listener.go:42] Got RTMP Stream: test

4. Now you have a RTMP video stream running, we can view it from the server. Simply run ffplay http://localhost:8000/stream/test.m3u8, you should see the hls video playback.

Integrating LPMS

LPMS exposes a few different methods for customization. As an example, take a look at cmd/lpms.go.

To create a new LPMS server:

//Specify ports you want the server to run on, and which port SRS is running on (should be specified)
//in srs.conf
lpms := lpms.New("1936", "8000", "2436", "7936")

To handle RTMP publish:

	lpms.HandleRTMPPublish(
		//getStreamID
		func(reqPath string) (string, error) {
			return getStreamIDFromPath(reqPath), nil
		},
		//getStream
		func(reqPath string) (stream.Stream, stream.Stream, error) {
			rtmpStreamID := getStreamIDFromPath(reqPath)
			hlsStreamID := rtmpStreamID + "_hls"
			rtmpStream := stream.NewVideoStream(rtmpStreamID, stream.RTMP)
			hlsStream := stream.NewVideoStream(hlsStreamID, stream.HLS)
			streamDB.db[rtmpStreamID] = rtmpStream
			streamDB.db[hlsStreamID] = hlsStream
			return rtmpStream, hlsStream, nil
		},
		//finishStream
		func(rtmpID string, hlsID string) {
			delete(streamDB.db, rtmpID)
			delete(streamDB.db, hlsID)
		})

To handle RTMP playback:

	lpms.HandleRTMPPlay(
		//getStream
		func(ctx context.Context, reqPath string, dst av.MuxCloser) error {
			glog.Infof("Got req: ", reqPath)
			streamID := getStreamIDFromPath(reqPath)
			src := streamDB.db[streamID]

			if src != nil {
				src.ReadRTMPFromStream(ctx, dst)
			} else {
				glog.Error("Cannot find stream for ", streamID)
				return stream.ErrNotFound
			}
			return nil
		})

To handle HLS playback:

	lpms.HandleHLSPlay(
		//getHLSBuffer
		func(reqPath string) (*stream.HLSBuffer, error) {
			streamID := getHLSStreamIDFromPath(reqPath)
			buffer := bufferDB.db[streamID]
			s := streamDB.db[streamID]

			if s == nil {
				return nil, stream.ErrNotFound
			}

			if buffer == nil {
				//Create the buffer and start copying the stream into the buffer
				buffer = stream.NewHLSBuffer()
				bufferDB.db[streamID] = buffer

                //Subscribe to the stream
				sub := stream.NewStreamSubscriber(s)
				go sub.StartHLSWorker(context.Background())
				err := sub.SubscribeHLS(streamID, buffer)
				if err != nil {
					return nil, stream.ErrStreamSubscriber
				}
			}

			return buffer, nil
		})

You can follow the development of LPMS and Livepeer @ our forum