Dropped Output Frames for 720p60 recordings

Channels Android TV
#1

We recently upgraded our TV to a Hisense Smart TV (65H8G1) running Android TV. I am attempting to use the built in apps and NOT use a FireStick, AppleTV, etc. with this TV so that we have a unified front end and clean setup. Channels installs fine and runs great for 1080i recordings.

However, I have a constant problem with dropped output frames for 720p recordings (either a 59.94 FPS MPEG2 recording from HDHomeRun or a 60 FPS recording via TV Everywhere). Output drops a couple frames a second but less than 30 (so it isn't dropping every other frame). Playback is watchable but motion is a bit jittery as a result. I have not seen this issue before on other TVs that use either a Apple TV or FireTV Stick to run channels or when watching on iPad. I can watch the same recorded game using YouTubeTV at 720p60 and using their stats for nerds I do not see this dropped frame issue (may drop one or two after seeking but never during normal playback).

Server is a Raspberry Pi that is hardwired to the router/HDHomeRun. TV runs on 802.11AC and speedtest to server shows ~100mbps download and 3ms latency. I submitted diagnostics from the client but unsure if those go direct or if I have to find the file on my server to upload.

#2

Edited. Sorry I have the U7G which probably has a better CPU.

I have an U7G. I have not noticed any issues with either HDHR or TVE. My Channels client is 4.1.3 with Surround Sound on and Decoder set to Hardware. I don't recall if those were default settings or not. I've never used WiFi as I've had it ethernet connected since new; can't comment on performance over WiFi.

Thinking about your Speedtest, I had issues with FireTV stick 4k Max on WiFi with FF/RW and that was showing speedtest in the mid 200s. Connecting to wired resolve the FF/RW issue for me. If you are only getting 100s, maybe you have some external interference that is not showing up during the speedtest runs. You have a wired computer to run a speedtest from the browser to verify your Pi is connected at gigabit? I had another Pi once connect at 100 a while ago. Has not happened to me since, but throwing ideas out there.

#3

Thanks for your reply.

Pi is definitively at Gigabit. Wired ethernet is not a realistic option for this TV with its location. Client WiFi speed however does not seem to be the issue as a 45-70 second buffer (content bitrate dependent as TV buffer size is 60MB) is easily maintained and refills after seeking/comskip in <5 seconds. No connectivity or bandwidth issues on YTTV, Netflix, HBO Max, Disney+, etc. using WiFi.

TV should be using default settings for the client and there is no soundbar, external AVR, or other connected to the TV.

Again, what I find odd is that this is exclusively happening with 720p60 (or 720p59.94) content. 1080i30 has no issue with dropped frames despite often having higher bitrates. The dropped output frames are occuring despite a full 45-70 second playback buffer.

#4

Does it happen on OTA channels? Is it happening in the official HDHR app?

Issues like this are common on built-in Android OS, and generally happen due to bugs in the hardware decoder and renderer.

#5

It does seem to happen to live channels (I rarely watch live, almost always via DVR) but again only if 720p60 and not 1080i30. I ran threw a few recordings and it seems to be tied to the 60 or 59.94 frame rate and not the resolution as a 720p30 TVE recording did not show dropped frames.

It's hard for me to tell if it happens in the official HDHR app as I don't see a way to show decoder output diagnostics in that app and the judder from the dropped frames is subtle (especially in daytime programming, it is somewhat easier to tell in sports).

#6

Have you tried the software decoder or hybrid (if an option)?

#7

I did try that yes and it made the problem much worse. I went from dropping maybe 1-5 frames per second to dropping like 50 per second.

I’m thinking it’s plausible that the built in hardware is incapable of 60FPS decoding. Which seems odd for a 2021 4K TV and is also odd that it happens for both ATSC (mpeg2) and TV Everywhere (AVC h264) recordings. Both of those are old codecs and not that computationally intensive.

#8

I was in your same boat. I bought a top tier sony tv and was determined to only use the internal apps and make everything be as clean as possible. I finally gave up after about 2 months and bought an Appletv. The processors on TV's are horrible, they cannot compete with literally any other streaming device. After switching to appletv (btw I am an android guy) I couldn't be happier.. I know you want a unified platform so what I would do is just unify behind appletv and use that device for everything. You seriously don't need the internal tv apps for anything. The last time the internal TV interface was used in my house was last night when my son accidently pushed the wrong button on the harmony remote lol. That was the first time in a year that it had been on.

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#9

I know this is an old thread, but I also have a HiSense model 55U6H. All 720P sources, OTA, TVE or recorded drop frames using any decoder. 1080 sources are just fine.