Bug 507015 - KRdp serves a grayish video stream (looks like a limited range video displayed as full range)
Summary: KRdp serves a grayish video stream (looks like a limited range video displaye...
Status: CONFIRMED
Alias: None
Product: KRdp
Classification: Plasma
Component: general (other bugs)
Version First Reported In: 6.3.5
Platform: Debian stable Linux
: NOR minor
Target Milestone: ---
Assignee: Unassigned bugs
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2025-07-14 08:12 UTC by Rongrong
Modified: 2025-08-27 17:02 UTC (History)
3 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:

Attachments
KRdp_KRDC (234.92 KB, image/png)
2025-07-14 08:12 UTC, Rongrong 		Details
KRdp_Remmina (350.19 KB, image/png)
2025-07-14 08:13 UTC, Rongrong 		Details
OBS_Studio_Screen_Capture_PipeWire (349.55 KB, image/png)
2025-07-14 08:13 UTC, Rongrong 		Details
Sunshine_Moonlight_H264_422 (1.15 MB, image/png)
2025-07-14 08:14 UTC, Rongrong 		Details
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Description Rongrong 2025-07-14 08:12:17 UTC 
Created attachment 183213 [details]
KRdp_KRDC

SUMMARY
KRdp serves a grayish video stream. It looks like something you get when plugging a legacy HDMI monitor into a modern computer, i.e., a video stream with a limited (16-235) quantization range displayed as full (0-255) quantization range.

STEPS TO REPRODUCE
1. Set up krdpserver
2. Connect to it with KRDC or Remmina
3. See a grayish video stream

OBSERVED RESULT
The video stream is grayish. Meanwhile, Screen Capture (PipeWire) in OBS Studio and Sunshine+Moonlight (H264 YUV422) all show correct colors. See attachments for details.

EXPECTED RESULT
The video stream shouldn't be greyish and should show correct colors.

SOFTWARE/OS VERSIONS
Operating System: Debian GNU/Linux 13
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.13.0
Qt Version: 6.8.2

ADDITIONAL INFORMATION
I've tried building KPipeWire+KRdp 6.4.2, and this issue is still reproducible.
Comment 1 Rongrong 2025-07-14 08:13:09 UTC 
Created attachment 183214 [details]
KRdp_Remmina
Comment 2 Rongrong 2025-07-14 08:13:35 UTC 
Created attachment 183215 [details]
OBS_Studio_Screen_Capture_PipeWire
Comment 3 Rongrong 2025-07-14 08:14:31 UTC 
Created attachment 183216 [details]
Sunshine_Moonlight_H264_422