Emulating an HDHR source?

Channels DVR Server Troubleshooting
#1

I am testing an HDHomeRun emulation on an Nvidia Jetson Nano. Everything I want to do is working fine with VLC so I got ready to add source to Channels.

In case it helps, I have network channels I want to encode (H264) and I can do it super fast on the Nano GPU. I can preserve AC3 and strip all the other streams I don't want.

But for a reason I haven't determined, Channels App goes to HDHomeRun IP when tuning instead of Nano IP.

Here's the guide returned from HDHomeRun:

{
  "GuideNumber": "5.1",
  "GuideName": "WPTV-TV",
  "VideoCodec": "MPEG2",
  "AudioCodec": "AC3",
  "HD": 1,
  "Favorite": 1,
  "URL": "http://10.0.1.89:5004/auto/v5.1"
}

And here's what the Nano returns to Channels for same:

{
    "GuideNumber": "5.1",
    "GuideName": "WPTV-TV",
    "VideoCodec": "H264",
    "AudioCodec": "AC3",
    "HD": 1,
    "Favorite": 1,
    "URL": "http://10.0.1.101:5004/auto/v5.1"
  }

As you can see the URL and VideoCodec are changed. What am I missing? I tried changing channel numbers so they were unique but then guide fails. (The DeviceID's and FriendlyName are different.)

Tl;DR: Even though channels gets a new URL for the source, it still goes to the HDHR URL when tuning.

#2

Emulating HDHR will not work.

I would recommend you use the Custom Channels interface and export an m3u

#3

FYI - I removed the source and restarted. My fake HDHomeRun no longer shows in channels/admin/settings but I noticed I keep getting requests for /discover.json from channels so channels is still looking for it.

#4

You should be able to add the emulated tuner by IP while disabling the originalHDHR(you could block UDP packets from that IP). The discovery is a little bit more complex than what you are tackling here. Part of it are broadcasts which you are still seeing on the emulator.

#5

I successfully "emulated" a remote HDHR by allowing access by its private IP. I needed to open not only TCP ports 80 and 5004 but also TCP/UDP 65001 in order to get signal strength.

  • The clients ignore the the port specified in lineup.json and always use 5004
  • A lot of time went through trying to convince DVR to forget the public IP of the HDHR and use only the private address
  • Deleting a source is almost impossible.
#6

Responding in case others get here. I thought emulation would be best and homerun api is simple to emulate. However, it seems channels has a special relationship with homerun and as tmm1 succinctly stated "Emulating HDHR will not work" so I abandoned that approach.

Instead I used the custom interface as recommended. It's done and working great and actually took very little code in the end.

Basically I change guide channel numbers so there'll be no confusion in channels such as HomeRun 5.1 becomes custom 510. When I get a request from channels to stream 510, I do the following:

  1. Set up ffmpeg using the homerun stream as input and encoding with the Nvidia h264_nvmpi or hvec_nvmpi encoders and output into a pipe. This can easily be done in real-time.
  2. The external ffmpeg process is managed with a twisted protocol class that keeps sending request.write(data) to channels dvr.

It's basically one file with a few device classes tying it together with asynchronous deferreds. Simple http protocol.

Now I can watch/record outside the home with high-quality streams at a significantly lower bandwidth with a lot of transcoding options.

#7

You could also run channels dvr on the nano and let it transcode. Or feed into another dvr with m3u.