ATSC3 just launched in Indianapolis two days ago. My HD Flex 4K found them in one scan - four major network affiliates on one RF channel. The Channels Plus client for my FireTV stick exhibits gaps in audio and slo-mo video, maybe 3 or 4 fps on all 4 sub-chanels. The Channels Plus app for my iPad2 is smoother, but still a subnormal frame rate. The Silicon Dust HDHR app on the FireTV displays all four of them perfectly, as does the Channels Plus app for my AppleTV 4K. The Flex 4K is getting a solid RF signal, around -40dBm with negligible tilt. The station may still be in startup mode, but this seems strange. 'Any clue in the differences between your apps on the different platforms as to what might be wrong?
What is the video decoder set to?
Decoder in which device? i cant find that option anywhere.
It should be on the FireTV. Depends what model it is?
It should be under Channels app Settings > Playback > Advanced > Video Decoder
Aha! The FireTv Stick was set to Software decode. Changing it to Hardware decode solved that problem. The iPad is an ancient iPad2 with no hardware decode support, but taking another look, it now seems to be playing fine, possibly due to its equally ancient screen resolution. I may have misjudged it.
Thanks for the assist, Aman. You guys are the greatest.
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There seems to be a minor side effect of the selection of hardware decode on the FireTV Stick 4K - when I play a recording from my Pi4 DVR server, the very first frame is rendered in blocks over the course about a half-second. All normal after that. 'Not worth fixing, just interesting.
This is generally known as macroblocking. It happens when the beginning of the file didn't have enough info to describe a proper frame, only the parts that had changed. Once a full reference frame is received, the video decoder knows how to construct the full picture properly.
This is due to the nature of how the video is sent: as a stream in progress. Since your stream missed some of the beginning, it looked wonky to begin with. There's nothing broken or wrong, that's just how video streams work.
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Thanks. That's what I thought. The DVR server doesn't "know" how the client is configured, so it sends what it has. The FireTV's software decoder must have been coded to wait for an I-frame, whereas its hardware decoder doesn't. A curiosity, really.
I cannot watch ATSC3 live on a Fire Tablet 10" (2021, i.e. current, generation). I get audio, but the video is black. I haven't made a recording yet, so I don't know if playback is any different, I will be recording stuff soon, so I'll know in a few hours.
I just checked and I have the same problem with a 10" Fire Tablet running OS 7.3.2.2 on two ATSC3 stations, a lighthouse with everything but PBS and a second one operated by the local PBS affiliate. I never noticed because we normally use an iPad2 or an AppleTV and no problem with either of those.
The usual problem with ATSC3 is no sound due to lack of an audio CODEC in the client device. This is the first I've heard of no pix. Maybe the Channels Devs will see this and weigh in.
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I updated the Fire Tablet OS and tried again, no video. I changed the Channels Client Advanced setting to Software decode. I now have video, but the video's in slo-mo. The Fire Tablet was purchased as a throwaway to run some other Android-only app. It probably doesn't have the CPU horsepower for software decode.
Did you try the HDHomeRun app ? Because you will see you will not get Video either. not a Channels DVR problem.
I have 4 networks doing ATSC 3 (HEVC/AC4) in my area. 1 of those networks I cannot get at all ATSC 1, 1 of them is sketchy, so I really need ATSC 3 to work, which is why I'm checking out Channels again (because Plex has the audio issue). I recorded 3 shows from 3 different networks, two of which have the same audio-only issue, one works. Looking into my logging, I see that Channels chose to use the ATSC 1 tuner to record that version instead of the ATSC 3 tuner.
I don't understand why the fact that HDHomeRun has the same problem means that it's not a Channels problem. It's a problem they both share and may have the same underlying cause, but it's still a Channels problem [too].
It is a FireTV Tablet problem they play great on my Samsung Tablets but not on FireTV tablet.
Fire tablets are junk... I could sugar coat it but you get what you pay for... You could try putting a ticket in with Amazon but I think you would be wasting your time.
To put a ticket in with Amazon, I would need Channels to tell me what function/feature/API isn't working correctly. Otherwise, Amazon will just correctly tell me that they don't provide application support for applications they don't provide.
And yes, they're not as powerful as the more expensive tablets, but it makes them attractively disposable.
Does it work on the official HDHR app or not?
It sounds like the hardware does not support HEVC codec. We would need diagnostics from the app after playback to investigate.
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it does not work on the official HDHR app only get audio.
It says that they do support H265 ...
VIDEO CODECS
H.263 D (HW) baseline, 1080P@30fps
H.264 AVC D (HW) High profile, L4.1 1080p@30FPS, E (HW)
H.265 HEVC D (HW) Main Profile L4 1080p@30FPS
MPEG2 D (HW) 1080P@30FPS
MPEG4 D (HW) Advanced Simple Profile@L5 1080P@30FPS
VP8 D (SW)
VP9 D (SW)
VC-1 D (SW)
VIDEO FEATURES
Low Latency Video
H.264 DRM Supported
H.265 DRM Supported
OpenGL ES 3.2
Fire Tablet Specifications: Fire HD Models | Fire Tablets (amazon.com)