Channels & viewing

[2ka]

@jbsjbs, I think this is really interesting.  I can't think why it should be, unless the color information in the original MKV file is messed up somehow -- and it gets fixed when it gets recontainerized.  If you are able, please post a link to the original MKV file or a snippet the demonstrates the problem.  I'd be happy to try to diagnose further.

[1DayAfterAnothe]

OK... two Roku Ultra's here. The one in my room is from 2019...the other one in another room is 2021....As has been discussed here...the 2021 one has the red issues with certain files...Even turning off AAC stutter and allow direct stream and direct play as auto...and playing some HEVC files that are DIRECT PLAYING both audio and video (HEVC AAC 2 channel audio)... and checking the Plex status from the server shows it's direct playing both...Not direct streaming.... and it was still red....on the 2021 Roku... I thought direct playing would eliminate this but apparently not.... anyway... I quickly changed those files to an MP4 container and put them back on the drive and plex refreshed meta data and the color was normal..

My question is this... Is the AAC stutter workaround still a thing? I'd love to leave it off... I distinctly remember when that issue came up and I totally noticed the sound would be intermittent clicking sound and I remember soon after that they introduced that so that anything with AAC audio would direct stream instead of direct play which fixed that....But the files I remember that problem on play perfectly fine now on direct play....with no audio issues  (same exact files I remember the stutter on)..

It's so frustrating to have to deal with this...Luckily it doesn't look like I have a huge amount of files that display this issue when browsing through...but I have such a huge library...Most everything I have I make sure before I put it on plex that it can direct play because I don't want my server to have to transcode anything..

[2ka]

Hello @1DayAfterAnothe,

It appears you might have missed, or at least you didn't mention, the most critical step.  You need to remove the color information from the MKV header of your original file using a tool like MKVToolNix.  It is the color info in the MKV header that trigger the color distortion bug.  Of course it also works to recontainerize to an MP4 container, because it doesn't have an MKV header at all -- so no color info to trigger the bug.

The whole reason Direct Play is important is that if Plex decides to Direct Stream, it will use an MKV container and add the color info back in!

The AAC stutter workaround can be a thing still, but it only affects some AAC tracks (AAC/HE).  You may find you can live without it entirely.

I do wish the Plex folks would give us an "HEVC Color Bug Workaround".  It would be easy -- just suppress color and color mastering info in the MKV header.

[2ka]

Oh, and if your library is large, as mine is, at least you probably don't have to do every file.  the bug only affects HEVC content that uses the BT.709 color space.  Generally this means HD or FHD content that was originally distributed on Blu-Ray.  DVD (BT.6010 or UHD HDR (BT.2020) content isn't a problem.

[1DayAfterAnothe]

Based on what you said it sounds like you have to do every file individually - or at least check every file...that would be a monumental task..

[1DayAfterAnothe]

Oh and the reason I just recontainerized without removing color (at least on this particular series) is because the files were AAC 2.0 and HEVC which will direct play... I understand that Plex can possibly direct stream that which will give me the bug all over again...but I think that's unlikely as long as I have direct play enabled (at least with HEVC and 2.0 AAC..

What confuses me is that I thought files being direct streamed were causing the bug to show....and that if that same file were direct played (even though that file has the offending color bug info) the bug wouldn't show....

It must have something to do with the audio... Take two series I have... Both HEVC but one is AC3 2.0 and the other is AAC 2.0.. When direct streaming both show red...but then direct playing the AAC still shows red... again, direct playing... while the AC3 2.0 plays perfectly fine (both still have the color information in them) Both are direct playing..... why is one red and the other isn't? 

[1DayAfterAnothe]

Hey - could you possibly tell me exactly where in mkvtoolnix under header editor/ color information... what I'm supposed to be looking for? I'm not seeing that code....what exactly do you do? I see "reset this value" currently what I'm looking at the value is 1 under color matrix coefficients ...when I reset the value it stays one... I guess I need idiot instructions LOL... I can't imagine the change would happen without remuxing the file? Maybe I'm wrong... what is the process?

[2ka]

Sure @1DayAfterAnothe,

Look for a checkbox that is labeled "Remove element".  Check that box on every one of the elements under color information.  Then save the file from the Header Editor menu.  You may want to keep a copy of the original file in case you screw it up until you gain confidence in this method.

You normally have to do this for color matrix coefficients, horizontal and vertical chroma siting, color range, transfer characteristics, and color primaries.    It is good to check all the elements of the color mastering information as well, but often they won't be set.

I can understand that it would be a big effort to go over every file in your library.  In my case, most of my content predated the HEVC (H.265) codec, so that eliminated 90% or more.  Anything encoded with H.264 is OK.  Super newer stuff is HEVC HDR (BT.2020), so I didn't have to look at that.  What was left was a small portion.  Only HEVC encoded material using the BT.709 color space is affected. 

Roku could fix this for us by fixing the bug.  Plex could fix this for us by providing a workaround that would suppress the color info in MKV headers when direct streaming.  Neither seem to care all that much.

[1DayAfterAnothe]

@2ka Gotcha... I think I've figured it out....though going through all the video color properties...chroma sting...color matrix coefficients...etc. I now understand how to remove them but I'm not seeing this BT.709...or anything BT anywhere....I guess my question is.. where exactly are you seeing that?

One good thing... at least we don't have to actually remux the files... although it's still difficult to do this to each file one by one...

Someone on the Plex forum said it would be super easy for Plex to make a workaround such as they did the AAC stutter workaround since Roku won't fix this bug....I guess the workaround could easily tell Plex not to use the color properties in the MKV or something like that....

Thanks for responding

[1DayAfterAnothe]

Just want to let you know it's totally working.... Yesterday I had removed some of the elements but not all of them... It was still showing red.... as you just said I removed all of them... (there were several) and it's no longer red.... OMG what a PAIN though. LOL... I do keep 2 backups of each file but so far it doesn't seem to be corrupting the file in any way at all. It's crazy to me that this is even a thing in 2022