Posts by jd17

    HEVC (x265 / H265) videos are not properly decoded on S905X, maybe all AMLogic devices (?).
    "Stained" double contours are visible.
    Both 8bit and 10bit HEVC videos are affected.


    Device type:
    S905X
    Build:
    All builds are affected. Jarvis, Krypton and Leia. Marshmallow and Nougat Kernel.
    Device:
    Mini M8S II 2GB/16GB


    How to reproduce:
    Compare linked x265 encodes to x264 encode.
    Compare x265 on AMLogic box to other players.


    Get close to the TV and look at the text edges, you can pause and look at a still frame too.

    The text edges are not clean on the x265 encodes, while they are perfectly clean on the x264 encode.

    The whole text should be pure yellow, as it is on the x264 encode, but the edges have a white-ish shimmer (or highlight) on the x265 encodes (left edge of letters).


    The x265 encodes look clean (all yellow letters) with other platforms and players:
    - Kodi Windows
    - VLC Windows
    - TV's internal media player


    Sample:
    I created short samples showing end credits with yellow text on black background:
    Uploadfiles.io - contour issue samples.7z


    Support logs:
    I don't think logs will help here.
    However, I can supply logs later if needed.

    For me it looks like the x265 ones are right, Yellow text with highlight from the left. Are you certain that its not the x264 decoding that's just doing a bad job? :angel:

    Yes, I am certain. The highlight from the left is not supposed to be there. Every other player gets it right:
    - Kodi Windows
    - VLC Windows
    - TV's internal media player

    You can not tell AVC and HEVC apart on these players.

    OK, I found a good example.
    The end credits from "Silicon Valley" - yellow text on black background.

    Download link:
    Uploadfiles.io - contour issue samples.7z

    Get close to the TV and look at the text edges, you can pause and look at a still frame too.


    The text edges are not clean on the x265 encodes, while they are perfectly clean on the x264 encode.
    The whole text should be pure yellow, as it is on the x264 encode, but the edges have a white-ish shimmer on the x265 encodes (left edge of letters).

    ...some of your HEVC encoded videos (short excerpt both 10bit and 8bit) for us to test and make sure that it's not a hardware problem?

    1. Just to repeat this so there is no misunderstanding - my assumption that 10bit was the root cause was wrong. It's a global HEVC decoding issue (at least for my box) and applies to 8bit HEVC as well.

    2. A hardware problem is of course possible, which is why I will gladly accept your help to test samples! :)

    I fear you might be misinterpreting the degree, which is probably why you think there is no issue - I would have reacted the same way.

    To make this clear, I am talking about a subtle issue, that you will probably not notice from common viewing distances to your TV, depending on the TV's size of course.

    I myself only really noticed it when I looked for improvements from that NR off command.
    I merely had suspicions before that.

    You need to get close to the TV and compare to a player that does not have that HEVC decoding flaw (TV's internal player in my case).

    Only when you have that comparison you will really notice.


    The best way to see it is high contrast straight edges, like from colored text - this is where I noticed.
    I will try to find a good example and encode a short sample for you guys.
    I'll upload as soon as I can!

    My encodes are flawless, indistinguishable from the source.


    The TV's internal media player does not show these false contours (and neither do PC software players) so the root cause is not CRF vs. bitrate.


    I will however recreate those encodes with Hybrid to rule out HandBrake as root cause, but I don't have high hopes.

    This looks like a decoding issue to me.

    This is odd, I have a few encodes in HEVC 10bit, some of which I did myself to test picture quality for different settings. Same-bitrate 10bit and 8bit HEVC files from a high quality source are undiscernable (to me, at least) when played on the S905. I most certainly never had any trouble with double contours. Also all European 4k DVB-S2 transmissions are 10bit HEVC, I would have noticed any visible image quality problems.


    Maybe it is something specific to the encode? Did you do it yourself?

    Funny coincidence, I just encoded the same sample again in 8bit to confirm it's a 10bit issue...

    ...just to find out it's not!

    It's an HEVC issue, the 8bit file shows the same blurred contours.

    Yes, I always create my own encodes.
    x265 2.5-4, preset slow, CRF17, no-sao (my standard for transparent encodes).


    Edit: I stupidly compared to the AVC source before.

    I will test an old Jarvis Marshmallow and your latest Leia test build today to see if the issue is gone in either.

    Leia testbuild: issue present.
    8.0.2e (last Krypton Marshmallow): issue present.
    7.0.3.012l: (last Jarvis, Marshmallow): issue present.

    Unfortunately, all builds show the same issue.
    10bit videos are not being displayed at proper image quality -> double contours.

    As there anything you can do about this?
    Do you want me to provide samples?

    Unfortunately, I discovered something else today - I hope you can help with this johngalt:

    10bit video (regular 1080p) has weird double contours.
    That noise reduction on/off has no impact on it and neither has the output mode, it's the same for both 8bit and 10bit.


    The same video (10bit) is fine on the TV's internal media player and the same video in 8bit is fine on the S905X too.

    I will test an old Jarvis Marshmallow and your latest Leia test build today to see if the issue is gone in either.

    Nevermind... I just thought I could compare a still frame when I pause the video und switch between 0 and 1.


    Unfortunately, I discovered something else today - I hope you can help with this johngalt:

    10bit video (regular 1080p) has weird double contours.
    That noise reduction on/off has no impact on it and neither has the output mode, it's the same for both 8bit and 10bit.


    The same video (10bit) is fine on the TV's internal media player and the same video in 8bit is fine on the S905X too.


    I was not able to take a good picture, but one side effect is that the bottom edge of the video is not clean, but rather looks like it is somehow "mirrored"? Those field lines should run out smoothly and not have that kink at the bottom edge:
    7MQc3A2.jpg

    TIP


    If anyone is seeing Ghosting or Smearing video playback on S9xx devices you can try turning AMLogic Noise Reduction OFF which is usually turned ON by default:


    Code
    echo 0 > /sys/module/di/parameters/nr2_en

    Thank you for the tip!
    I never saw those kinds of issues and to be honest, after putting this line in the autostart.sh and rebooting, I don't see any difference...

    Do you maybe know a good sample where you can see this ghosting/smearing easily?
    I would like to compare and see for myself...

    Hi john.. :)

    Any revelations regarding the vertical lines in 2160p?
    Is there even any hope of fixing this?

    I remember last time you said that you don't have a clue where it is coming from...
    I just thought I'd ask, maybe you (or someone else) had an idea of how to fix this. :)



    As far as I see it, those lines are the only thing keeping the S905X from being the perfect UHD playback device.

    First thing I would try to change the power adapter. Some box comes with awful ones...

    Mine seems fine, at least visually...
    But I had that idea too, I'll try to find an alternative.

    Quote

    The official firmware is v1.15 (2017.06) Yandex.Disk I haven't tried it because I flashed LE to my box.

    On 4pda there is an android 7.1 image too.

    Thank you!


    There are multiple custom roms for the Mini M8S II - both Marshmallow and Nougat, including AndroidTV builds.There are at least 4 custom roms on FreakTab. They are much better than stock. You can find the firmwares over on Freaktab here:


    Code
    http://freaktab.com/forum/tv-player-support/amlogic-based-tv-players/s905x/others-aml-s905x/firmware-roms-tools-bx

    Thank you - do you know how to flash these if LibreELEC is on internal?


    Quote

    Only other thing to consider is - how long ago did you buy the box? With the regular s905 box, there were several revisions of the CPU. The early revisions had hardware bugs in them, but this was eventually corrected. Not sure about s905x.

    My Mini M8S II was shipped December 28th 2016...
    I don't know if there were any newer hardware revisions...?