Video requires black background in order to work normally

[bnovakovic]

Steps to reproduce

• Checked out your main branch
• Windows is set to light mode
• Start the sample app
• Click the play button

Expected outcome:

• Video should play normally

Actual outcome:

• Video is barely visible

Workaround:
Open PlayerComponents.kt -> Line 90
For modifier add .background(Color.Black)
All works normally now.

Attached is video showing steps and bug.

bandicam.2025-08-10.23-33-42-110.mp4

[kdroidFilter]

It's very strange, I don't have this problem on my PC. The video displays correctly on my computer. I have to check this

[bnovakovic]

It's very strange, I don't have this problem on my PC. The video displays correctly on my computer. I have to check this

Yeah that's strange. Could be how window is rendered as per OS. Here is my system info in case it matters to you

[KamilSucharski]

Can confirm - In the sample (dark mode) the colors looked washed-out by default, but after changing the background to black in VideoDisplay's Box view (was MaterialTheme.colorScheme.surfaceVariant) it looks better. It seems the colors of the player get multiplied by whatever is underneath it.

[StefanOltmann]

Confimed.

Thank you for pointing me to this workaround.

[kdroidFilter]

Fixed in #194.

The root cause was that Windows Media Foundation outputs video frames in BGRA format with the alpha byte set to 0x00. When drawn with the default SrcOver blend mode, the pixels were treated as fully transparent and blended with the background color — making the video nearly invisible on light backgrounds.

The fix uses BlendMode.Src for video frame rendering, which replaces pixels directly without alpha blending. This ensures consistent, correct rendering across all background colors and themes.