Sony Bravia 9 - Local Dimming Bug when viewing HDR / Dolby Vision

[JonathanYL]

Description

When playing 4K HDR or Dolby Vision content, the local dimming is not applied on Sony's flagship 2024 mini-led TV the Bravia 9's on board Stremio Android TV app. This results in elevated black bars and a slightly washed out picture.

Steps to reproduce the behavior:

1. Open Stremio and select a 4K HDR / Dolby Vision movie - examples used were Dune, Strange Darling, The Batman
2. Notice that the blacks and black bars are elevated / blotchy - meaning local dimming is not enabled
3. Now select the same 4K SDR movie
4. Notice that the blacks and black bars are pitch black - meaning local dimming is enabled

Expected behavior

Black bars and black screens should be black and not elevated.

Screenshots

• Stremio 4K HDR Dune
  

• Stremio 4K SDR Dune
  

TV

• Device: Sony Bravia 9
• OS: Android TV
• Android OS Version: 12
• Stremio Version: 1.6.12

Additional context
Other users on avsforums reported the same issue with the latest firmware. One user reported a similar issue with Plex where the Plex developer fixed the issue by removing a layer in their app. Here is the link and quote:

This is not a Bravia 9 issue, this is an internal app issue. Thats the same problem Plex had before. The Plex Dev told me he did the following to fix it:

"Thats amazing news, so we removed a layer that’s supposed to stop ghosting effects on Sony TVs, which may bring some other issues. (But it might only be for old Sony TVs hopefully) "

I think you need to contact the Stremio and HBO Max support and tell them to remove the same layer on their internal apps to get Local Dimming working.

This most likely affects the Bravia 7 as well since both the Bravia 7 and Bravia 9 are mini-led tvs. I don't believe you will see this issue on OLED tvs since they don't have local dimming.

[TRtomasz]

So when you plax hdr video in Plex it is now dimmed correctly? What if you play in vlc/just player as an axternal player?

[JonathanYL]

I did not try Plex. It was just something I found on the avsforums. I tried the libvlc player and external player (just player) and the same bug occurs.

[TRtomasz]

So clearly it is not stremio issue, but some kind of hardware limitation

[JonathanYL]

Just to clarify, I tried exoplayer, libvlc and justplayer from the stremio playback options. That's the only time I see the local dimming bug occur. I'll try to play some hdr content from usb on justplayer tonight and report back.

[JonathanYL]

Apologies for the delay. I have no issues with local dimming when playing hdr videos on justplayer that's on the tv storage.

One interesting thing I saw is that the same content on Stremio sometimes produces different results. Bladerunner 2049 in HDR will sometimes display black content properly with the local dimming activated and sometimes it does not and produces elevated blacks.

Any idea what may be the issue here? Stremio is the only app where I've seen this happen. All the other onboard apps: YouTube, Amazon, Sony pictures core work fine. I've sent my findings as well to the Sony support team.

[JonathanYL]

I found that Nova Video Player as a stremio external player was able to play The Batman in HDR with perfect blacks while all other players such as exoplayer, libvlc did not. This was 100% reproducible on my end.