HD playback on a Pi3?

[cliveb]

Having built a new 0.31 backend on a Pi4, I decided to try putting a Pi3 into service as a front end.
Using MikeB's helper scripts, it all came together quite easily, and works a treat on SD recordings.
But HD recordings are a problem. After applying all the various tweaks I could find (Video playback profile updates, GPU memory increases, seting the CPU to "performance"), it now sort of plays HD recordings, but takes a while (anywhere between about 3 and 10 secs) for the video to settle down, not only when playback starts, but after any seeking.

Is the Pi3 just not quite up to playing HD recordings? (These are UK Freeview HD recordings, BTW)

[jfabernathy]

IMHO the RPI3 is not good at all for HD. You can make it acceptable to some by installing only LibreELEC with the pvr-mythtv addon. My wife thought that was okay before we got a FireTV 4K stick. The FireTV 4k is cheaper than the RPI3 or 4, and works much better as a frontend.

I've moved all my RPI3s to task like PI-hole, etc.

To me the RPI4 is a very good backend, but to me only good for HD as a combo FE/BE if I use Kodi 18 with the pvr-mythtv addon.

Of course your mileage may vary. Video is very subjective. I'm very sensitive to jitter is a signal. Drives me crazy.

I guess I should add that all my recordings are ATSC OTA HD 1080i or 720p USA stuff

[cliveb]

IMHO the RPI3 is not good at all for HD. You can make it acceptable to some by installing only LibreELEC with the pvr-mythtv addon. My wife thought that was okay before we got a FireTV 4K stick. The FireTV 4k is cheaper than the RPI3 or 4, and works much better as a frontend.

Thanks for the comments. I'll investigate the LibreELEC and Firestick options, and there's always the fallback position of just buying Pi4's for frontends.

[jfabernathy]

IMHO the RPI3 is not good at all for HD. You can make it acceptable to some by installing only LibreELEC with the pvr-mythtv addon. My wife thought that was okay before we got a FireTV 4K stick. The FireTV 4k is cheaper than the RPI3 or 4, and works much better as a frontend.

Thanks for the comments. I'll investigate the LibreELEC and Firestick options, and there's always the fallback position of just buying Pi4's for frontends.

Again it's personal preference, but FireTV 4K is half the price of RPI4 4GB and IMHO far better at MPEG2 OTA HD content. Not sure what your content is, but anything I have to watch is not as good on the RPI4 as on FireTV 4K, Nvidia Shield TV or any of the Android options I've tested.

Good luck with your choice.

[cliveb]

Again it's personal preference, but FireTV 4K is half the price of RPI4 4GB and IMHO far better at MPEG2 OTA HD content. Not sure what your content is, but anything I have to watch is not as good on the RPI4 as on FireTV 4K, Nvidia Shield TV or any of the Android options I've tested.

Thanks for the additional advice.

I've had a play with LibreELEC with the MythTV PVR Client. It actually installed and ran OK on a Pi2. Even HD playback was just about OK. But I found the interface a little strange.

I have a Firestick (not a 4K one) and decided to play with that.

First, I tried the "leanfrontend". Playback of SD recordings worked but was painfully unresponsive. HD playback never managed to actually start before I got bored waiting for it. And in any case, from what I saw, the interface is again a little strange.

Maybe I'm just too used to the "proper" front end interface. I've been living with it for years.

Then I tried the full-blown frontend on the Firestick. An attempt to install the 64 bit version failed, so I guess my Firestick is a 32 bit one. After installing the 32 bit version, starting it up and adjusting some of the configuration settings was just agonisingly slow. I had to force stop it and relaunch. But once it got started, actually watching and scheduling recordings worked OK. Playback of HD recordings just about worked, but you could tell it was teetering on the brink with occasional tiny glitches. Maybe a 4K version would be much more capable? At least the interface was familiar. Of course the Firestick remote is rather lacking in buttons.

I'm coming to the conclusion that the path of least pain is to just get more Pi4's to run other frontends. Sure, they aren't as cheap, but they just work.

[jfabernathy]

FYI. All FireTVs are 32 bit software. The Regular FireTV will not work for HD. The FireTV 4K is the one I use.

[jksj]

Weird I agree with Jim, playback on Fire Stick just works and get jitter on Raspberry Pi 4.
Tested on F4K and Fire TV Stick 2020 version, both work fine with HD.
Both particularly good with Leanfront.
I wonder if the good performance with Raspberry Pi is a function of the TV used, I could never get rid of jitter with mine.

[cliveb]

FYI. All FireTVs are 32 bit software. The Regular FireTV will not work for HD. The FireTV 4K is the one I use.

That's interesting, because I've seen multiple statements around the web that talk about some Firesticks being 32 bit and others 64.
So you're saying that although some of them have 64 bit hardware, the OS is always 32 bit?

Weird I agree with Jim, playback on Fire Stick just works and get jitter on Raspberry Pi 4.
Tested on F4K and Fire TV Stick 2020 version, both work fine with HD.
Both particularly good with Leanfront.
I wonder if the good performance with Raspberry Pi is a function of the TV used, I could never get rid of jitter with mine.

It's all a bit strange. I have no issues with HD playback on the Pi4 (4GB), but on my Firestick (not 4K, bought in 2019) Leanfront is painfully slow (and didn't work on HD), but the full frontend eventualy worked after hanging during config (with HD sort of working).
Of course there may be different types of HD - these are UK Freeview HD recordings I'm trying out.

But even though I could get it sort-of working on the Firestick (so a 4K one should be fine), it's not a viable option for me because the remote has so few buttons that there's no way to control all the functions I want to use.

[jfabernathy]

The FireTV 4K is kind of like the RPI4 in the sense that it's 64 bit architecture but the OS and apps are 32 bits. I know eventually the RPI4 will have a non-beta 64 bit OS, but not sure the future of FireTV 4K OS.

I tried my original FireTV and quickly gave up and gave it to my son who watches Netflix on a 1080P TV so it works for him. I bought my FireTV 4K on a Black Friday special a long time ago for $25. My wife uses it on a 1080P Sony XBR 6 that's old but still a great picture. She has no complaints with:
Netflix
Youtube.TV
Youtube.com
Prime Video
Leanfront
MythTV-Frontend

Since she only watches TV and I do all the maintenance she only uses Leanfront to watch the OTA shows we record.

I've heard that over the years Amazon has updated the software on the FireTV 4k to make it work better on UK content. But since I'm in the USA, I can't speak with any authority on that subject.

[jksj]

Leanfront was only recently updated to work reliably with Freeview UK HD (October 5th) N.B select ffmpeg for audio decode.
I have heard the original Fire Sticks were somewhat underpowered but it may be worth another try.
My quite old Sony Vaio which is seriously underpowered now works well with Leanfront but cannot cope with Mythtv frontend.

[jfabernathy]

I just saw a special deal on Amazon for the FireTV 4K for $29.99

[dddd]

I noticed vast problems with my Pi3B myth keeping up with playback when I upgraded from myth 29 to myth 31. I was able to mostly eliminate it with the dtoverlay of fake kms (see other posts).


However here are several other things I'd already done that others
might not have been doing:

Reducing the HDMI desktop resolution from 1080 to 720 produced a significant improvement in performance.

using OpenMAX EGLFS instead of MMAL produces a slight (but detectable to my eye) performance improvement. I haven't checked
lately if still required, but as part of my setup I did this:
ln -s /opt/vc/lib/libbrcmEGL so /usr/lib/libEGL so
ln -s /opt/vc/lib/libbrcmGLESv2 so /usr/lib/libGLESv2 so

increasing the GPU memory to 384 helped slightly

[gedakc]

@dddd what steps did you take to "reduce the HDMI desktop resolution from 1080 to 720"?

Also which version of MythTV are you running?

The reason I ask is because with MythTV 31 on my RPi4 there is no OpenMAX EGLFS playback profile. I think that profile is only available on earlier versions of MythTV.

Out of curiousity I also transfered my SD card to an RPi3 and there is still no OpenMAX EGLFS playback profile available for selection.

[dddd]

Both client and server are myth31 (which I indicated) so I assume you're asking about which myth compile. I'm using mythtv-light, installed this way on Raspbian buster:
echo "deb http://dl.bintray.com/bennettpeter/deb/ buster myth31
" >> /etc/apt/sources.list
wget -O - https://bintray.com/user/downloadSubjectPublicKey?username=bintray | apt-key add -
apt-get install mythtv-light

The EGLFS option was just there, I didn't need to do anything.

One more thing I forgot to mention, I did this which helped performance slightly:
echo "vm.swappiness=5" >> /etc/sysctl.conf

As for resolution, on earlier raspians it was enough to set it in config.txt, replacing old settings with this:
hdmi_group=1
hdmi_mode=4
framebuffer_width=1280
framebuffer_height=720

But in buster I had to run the screen configuration tool (menu option runs a program call arandr), and configure screen resolution.