Remux option

Channels DVR Server
#1

I'd love to see a Remux option inside the Android apps. With ATSC 3.0 and ac-4 my Nvidia shield hitches when playing the direct stream with the ac4 sound profile. It just can't keep up.

When I force a transcode by selecting 8mbps in the app, it forces the server to deal with it before delivery and my Nvidia shield runs it perfectly fine.

My only issue with this method is that I do have some OTA 1.0 stations that stream at a high bitrate, 10-15mbps. So I really don't want to be toggling this option on or off all the time.

Would it be possible to add an option in the player like Plex has to downgrade the quality for that stream or to add an option to Remux at the original (or close to it) globally? The "stream" option doesn't seem to be pre-emptively transcode the stream, because I still see the hitching.

Edit: Or could we have a feature to just transcode the audio during the recording process when it sees ac4 Audio?

#2

Please try the latest Android beta and let us know if it's any better.

#3

Ok, I'll give that a try.

#4

I tried the latest beta. The shield is still hitching with the audio unless I force a transcode with the bitrate home selection.

I did figure out how to loopback call the stream through channelsDVR with a custom channel and force a transcode, then I just record the custom channels output. Not a purist solution, but good enough for me.

I can submit diagnostics if yall want to look into it more too if you'd like, ATSC 3.0 is a mess right now, so I'd understand if you're still waiting for things to settle before you put to much work into it.

#5

Theres been documented issues on that front with using the Shield in the past. Did you try another device (like an Appletv or an onn box)?

#6

The Shield is the only thing I've tried outside of my phone, which doesn't appear to have the same hitching issue. But I did get a loopback call to the server to force it into a transcode, so I'm fine with that, it's working on my shield just fine with that.

#7

Have you tried switching the Video Decoder setting? This could be an HEVC video issue and not audio.

#8

I did switch from Hardware, Hybrid, and Software on the Shield. It got worse on the anything but hardware. I also unchecked the audio track in the options and it all smoothed out after that.

#9

Please play back something that is exhibiting these issues, then uncheck the audio track, confirm it smoothes out, and then submit diagnostics from the client.

1 Like
#10

Done. Just now, as of the timestamp of this comment.

#11

Please make a 5 minute recording of one the channels you are having problems with and upload it to: https://www.dropbox.com/request/MMjICRc053JJpSBPDIfQ

#12

I've been unable to get this captured in a video format that is noticeable, plus when I've asked others in my household if they notice it they say they don't, so maybe I'm hallucinating. Either way, I've just done a remux loopback call via a custom channel on the server and have the server trans-code the audio to aac from AC4 and it seems to work great.

I just snooped what the Shield was doing when I would force it to a specified bitrate and made some modifications to the stream call. Some of it might be necessary, some might not, but it's working so I'm rolling with it. I tried AC3, but that failed over to AAC anyway and even sometimes failed over to the spanish audio track.

Using the call below I get a copy of the video and the eng (first) audio track in AAC and that hasn't given me any issues since. I always watch super delayed, so the transcode delay doesn't bother me. I personally would like an option in the advanced settings to try and auto transcode ANY ac4 audio on the server side so my clients don't have to. I have a decently powerful server that can handle it.

format=ts&abitrate=384&acodec=aac&indexed=true&scodec=copy&ssize=1&vcodec=copy

#13

The client and the server are using the same code to handle the audio, so it's surprising that would be required.

#14

I doubt it has to do with the code. I just don't think that the shield has the power to software decode the ac4 stream in a timley manner. That's my theory anyway. There is a 5 second delay before ANY audio kicks in when the ac4 is selected as the audio track.

Every time I fast forward to far, that delay kicks in again until the decode catches up. My loopback is just recording the transcoded file. So when I go to watch it all the client sees is the aac audio track anyway.