Dynamic Range (DV/HDR10+/HLG BT.709) inconsistencies

[cdguy]

Hello @kingslay

I am facing inconsistencies with Ksplayer regarding the Dynamic Range Switch.

https://github.com/kingslay/KSPlayer/commit/f572bc1c76e962fca159db36096036702f493341

This last commit broke the way DV, HDR10+ properties are displayed on TV.

Issue 1: If DisplayCriteria is set to off, BT.709 (LiveTV) is considered as HDR and a dynamic range is triggered; however BT.709 content is SDR.

Issue 2 (General one): depending of DisplayCriteria enabled or not; DV works but HDR10+ is displayed as HDR10; or the contrary is happening (DV is broken but HDR10+ work sometimes)

Instead of adding toggles like FormatDescriptionDisplayCriteria ; one unified code would be easier to for everyone, because not all devs have knowledge or adequate equipment to test DV/HDR10+ content.

And it is also a waste of time for you too because every time you make changes to the dynamic range code, something gets broken and you spend your spare time to correct the issue.

I sent to you via e-mail 4 video files. you can either play them with your video player or download them.

[djokt]

Can you update tracy to test 🙂

[cdguy]

@kingslay can you please look at the video named "SDR - BT709" either way, there is no dynamic range switch. BT 709 is a 4K SDR stream.

[cdguy]

@kingslay I figured out that TracyPlayer does not recognize HDR10+ content as it should be. TracyPlayer is displaying the media info as HDR10. ( you can check with the link I sent you before)

Besides, I found a tool that recognizes if the content is in HDR10+ https://github.com/quietvoid/hdr10plus_tool

[cdguy]

https://github.com/quietvoid/dovi_tool https://github.com/Lypheo/vs-placebo

you can also check those if that might help @kingslay

[kingslay]

苹果的系统里面没有AVPlayerHDRModeHDR10+ 这个选项。只有下面三个选项。 typedef NS_OPTIONS(NSInteger, AVPlayerHDRMode) { AVPlayerHDRModeHLG = 0x1, AVPlayerHDRModeHDR10 = 0x2, AVPlayerHDRModeDolbyVision = 0x4, }

[cdguy]

the last code outputs correctly hdr10+ on the TV, I just wanted to underline that the "Video Type" label displays the wrong info when a HDR10+ is played

[kingslay]

目前Video Type 只会返回下面几个值。

   public var description: String {
        switch self {
        case .sdr:
            return "SDR"
        case .hdr10:
            return "HDR10"
        case .hlg:
            return "HDR"
        case .dolbyVision:
            return "Dolby Vision"
        }
    }

目前还无法判断一个视频是HDR10+ 。我会看下你提供的资源。看下能不能找到方法

[kingslay]

@cdguy 所以视频显示是不会有问题。只是Video Type 这个信息显示不对。是不是

[cdguy]

所以视频显示是不会有问题。只是Video Type 这个信息显示不对。是不是

Yes that's correct, the TV displays the correct info

[cdguy]

there is only one issue remaining: BT.709 encoded 4K SDR live streams are displayed SDR in tracy player via the media info page (correct) However, TracyPlayer triggers a Dynamic Range for this kind of stream. the image output should remain in SDR.

I will re-send to you the stream link via e-mail

[kingslay]

这个是因为这个视频的格式是 Stream #0:1[0x101]: Video: hevc (Main 10) (HEVC / 0x43564548), yuv420p10le(tv, bt709), 3840x2160 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn

视频的位深是10，所以就把它判断成hdr10。 之前我是不会根据位深来判断是不是hdr10，只根据transferFunction来进行判断。但是我记得之前有人提了一个bug。transferFunction是 bt709，但是视频内容是HDR10. 所以只能根据位深来进行判断。所以我们可能要找到一个更好的方式来判断Dynamic Range。不能根据transferFunction和bitDepth

[cdguy]

这个是因为这个视频的格式是 Stream #0:1[0x101]: Video: hevc (Main 10) (HEVC / 0x43564548), yuv420p10le(tv, bt709), 3840x2160 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn

视频的位深是10，所以就把它判断成hdr10。 之前我是不会根据位深来判断是不是hdr10，只根据transferFunction来进行判断。但是我记得之前有人提了一个bug。transferFunction是 bt709，但是视频内容是HDR10. 所以只能根据位深来进行判断。所以我们可能要找到一个更好的方式来判断Dynamic Range。不能根据transferFunction和bitDepth

I will close this thread as this issue is a rare one; thank you for your hard work!!