How does pausing Live TV for HD Homerun PVR work?

[zakaron]

Ever since I had MRMC set up, I've been using the MythTV PVR client to connect to my MythTV backend for live TV viewing. It is both nice in that it can pause the live stream, but not so good in that it constantly records. I recently started looking at the HD Homerun PVR client because my wife likes to leave the TV on at night and so it may end up recording on the backend all night and all day unless I remember to remote in from work and turn off that tuner. I was under the impression that using the HD Homerun PVR client just streams the content directly over the network and no pausing is possible. Well, to my surprise tonight while testing out this PVR, I was somehow able to pause live TV?!? I didn't think that was possible, so now that has me wondering how it it is buffering the content. Does is write to the Apple TV flash memory or just buffer in RAM? Is it constantly recording like MythTV or only when you pause for the first time? If it is writing to the flash memory, then I'm not sure I want to keep using that as it would add additional wear - I'd rather just use MythTV's backend that writes to my Freenas server. Thanks for any input on how this can accomplish pausing live TV.

[amet]

Hi,

I am not familiar with HD homerun devices, @ davilla might have more on them, but we definitely don’t buffer on AppleTV. All buffering/pausing actions are happening on the backend.

I use Tvheadend and it has a setting to enable/disable pausing and ff/rev functions , mythtv should have the same. Basically you should be able to tell mythtv how big the pause buffer needs to be.

[davilla]

not a clue I'd have to dig into the pvr code to see what it does.

[zakaron]

I'm glad I'm not the only one unsure about this

@amet, the HD Homerun (prime) is a fairly basic box - one coax input from the cable source, 1 cable card slot for decoder card, and 1 ethernet out. It has 3 built in tuners, 64MB RAM, 2MB flash. It connects to clients via DLNA. And that's about it. I am not signed up for their DVR service or anything like that.

I was doing more testing with this PVR client in MRMC and noticed under System Information that the PVR service had an available 1TB of drive space. Not sure where that would be coming from since the Apple TV only has 32GB and I had the MythTV PVR disabled so it would not even be looking at that.

Now I did give a thought about the other settings I have set - under system settings --> internet, I have the buffer at 40MB, all filesystems, and readrate factor 8. I pulled these settings over from an old Android box that used to give me buffering messages a couple times per minute while on live TV. The settings worked well on Kodi there, so I kept them the same for MRMC when I switched to Apple TV.

Another thing I noticed was that if I paused for more than about a minute or 2, then unpause, it would play back what's in the buffer (whatever is buffering), then it would actually exit back to the channel guide and stop the stream. If I pause for maybe only 30 seconds, it would continue to play the channel, but I did notice artifacts in the picture feed. So after all, it is not very good at live tv pausing.

One last thing I tested was to fire up Kodi on my PC and use the HD Homerun PVR add-in, and it actually behaved the same way with it allowing pausing for a bit and showing 1TB storage for the PVR, even though I only have 500GB mirrored disks in this machine with about 45GB free.

I'm not overly concerned about this, so please don't waste a lot of time on it. It was more for my curiosity because I like to understand how things work. But figured I'd pass this along in case anyone else is curious too.

[amet]

Heh, all pvr backends behave differently but one thing is the same, we don’t buffer internally except for the normal playback. So if you hit pause, you have told backend to pause and if it has that function enabled and can buffer internally , it will.

No idea where 1TB comes from, pvr addon queries that from backend and it should report available space on it. Tvheadend on my end does this correctly.

I know it doesn’t help much if I keep telling you that it all works just fine here, but that’s how it is

[timstephens24]

For the HDHomeRun there’s no real backend since it just streams from the HDHomeRun device itself. It would be nice if it buffered internally because right now the buffer is extremely short.

[cosmoxl]

My experience with DVBLink is that it'll pause so long as I'm in the same EPG "show".

I think I've only seen this once and all I remember is that playback suddenly began when time slipped into the next EPG time slot. I don't remember any other details.