Channels & viewing

[GoPenguins]

Sorry I didn't read close enough, you are having issues with mp4's?  Convert it to an mkv.

[jsharret]

I've got dozens of video files.  That's not really practical en masse.  I'd like to understand what is causing the issue to see if maybe not all need to be converted or to see if there is another issue/fix.

[GoPenguins]

Just download the Recompressor tool from Ennetran.

www.ennetran.com/Download

It can batch convert from mp4 to mkv.    And that conversion is fast.   In addition they will soon have a version to strip these image headers out so videos playback correctly on the Ultra.

No more transcoding for me!!!

[ftballpack]

No more transcoding for me!!!

If jsharret is seeing this problem with MP4 files, converting the file container to MKV will not help.

Rokus converts multichannel AAC to dual-channel AAC. To work around this issue, Plex will transcode multichannel AAC to multichannel AC3, allowing the Roku to correctly play multichannel audio.

The remuxed file with HEVC video and the newly transcoded AC3 is streamed to the Roku in an MKV, which is why people who use play MP4 files (which MP4 files are not subject to this glitch) see the color saturation issues.

One workaround is to convert multichannel AAC audio to AC3. HEVC + Multichannel AC3 audio in an MP4 container will not have this glitch. The other option is to force the Plex client on the Roku to not let the Plex Server transcode anything, which will force the Roku to convert multichannel audio down to dual-channel audio. If a person is using a surround sound system or a good soundbar, obviously the second option would create all sorts of other issues.

[GoPenguins]

Many of my movies were originally mp4.   Recompressor will convert them to MKV's and add stereo (if wanted) and add DD 5.1 (if wanted)

Mine have all been recompressed with Nvidia HEVC and B frames and added stereo and DD 5.1 and I stripped the color tags.   Then on my Roku I force playing direct.   I love not having to transcode.  And I get DTS 7 now and it's fast to play.

Problem solved.  I would be shocked if that didn't work for him.

[jsharret]

I've been playing around with enneTran, but I can only get it to half work.  I can't get an audio stream that my Roku is able to Direct Play.  I have a Roku Express 4k+.

When I force direct play it tells me there's no compatible audio, BUT the video plays perfectly.  No color saturation.

When I set direct play to auto, it transcodes, then I have audio but the color saturation returns.

My ffmpeg skills are limited.  I am able to copy the video stream from the MP4 into a new MKV container.  I have tried converting the audio to AC3 and EAC3 using different options, but no luck.  What should I be doing to get a compatible audio stream the Roku can direct play?

[GoPenguins]

This is fixable.

First and foremorst, keep your backup of your original mp4 for the time being.   🙂     I don't want to be responsible for it accidently getting removed.

So I'm thinking you followed these steps:

1) Ran profile "Convert to mkv" 

2) Ran profile "Strip Colour Header" and select overwrite source

3) Now run "Add Dolby Digital 5.1 and Stereo" and select overwrite source

You final mkv will have the proper video, along with whatever audio was in your mp4, plus a stereo track and a DD 5.1 track.

This should play without transcoding.   If it's transcoding, make sure you have selected the DD 5.1 stream in Plex.

[jsharret]

I did that try originally, but didn't have any success (even with selecting the DD5.1 stream).  I modified the ffmpeg instruction to just convert the audio outright to DD5.1 (-ac 6 -c:a eac3 -metadata:s:a:0 title="Dolby Digital 5.1") but it just won't work.  It keeps saying no audio is detected and that it is an incompatible audio encoding.

EAC3 (Dolby Digital Plus) should be supported.  My Roku detects it (settings->audio->hdmi).  The roku is directly connected to my Onkyo receiver.  I'm not sure if there's some setting in the Roku, Plex, or somewhere else that is wrong.

I have a Roku Express 4k+.  It should be able to do this I think.  https://developer.roku.com/docs/specs/media/streaming-specifications.md

[ftballpack]

If using FFmpeg, the following should work. For whatever reason when I tried this in the past, my AC3 5.1 audio seemed quieter than the original AAC 5.1 audio. It will 100% work to convert the audio but I never spent the time to figure out the volume issue.

ffmpeg -i input.mp4 -flags +global_header -movflags faststart -c:v copy -c:a ac3 output.mp4

This assumes only one input video stream and only one audio stream.

Ultimately I gave up on the 2020 Roku Ultra and found an additional 2019 Roku Ultra's which does not have the HEVC MKV container issues of the 2020 Roku Ultra. The 2020 Roku Ultra is sitting in a box in a closet. I gave up waiting on Roku to actually do something to fix the issue and refused to convert my entire library over to work around the 2020 Rokus.

Use the following if you want to output your audio to eac3 instead of ac3

-c:a eac3

[GoPenguins]

Did you happen to try to play the simple stereo audio track.  That should for sure work.

Just as a test.