Emulator

Game Name?

Super Smash Bros. Brawl

Game ID? (right click the game in the game list, Properties, Info tab)

RSBE01

What's the problem? Describe what went wrong.

Testing out HD textures for use in Brawl has led to learning about Dolphin's current hardcoded support of RGBA8 PNGs.

While that is good enough for most scenarios, gradient heavy images tend to have banding in the 8-bit color depth.

If attempting to use a 16-bit depth PNG, dolphin can render the image darker than usual or ignore it. Your mileage may vary.

What steps will reproduce the problem?

Use an image like the one included that has 16-bit depth color as an HD texture for Brawl.
After ensuring that it is named properly and placed in the correct location for Dolphin to load the image as an HD texture, issues like the one described earlier can occur.
If the image is ignored, the vanilla texture from the disc / iso will be used.
If the image is used, it can potentially render darker than normal.

Is the issue present in the latest development version? For future reference, please also write down the version number of the latest development version.

latest indev version, as far as I know.

Is the issue present in the latest stable version?

Yes, 5.0 stable

What are your PC specifications? (CPU, GPU, Operating System, more)

Windows 10
Processor Intel(R) Core(TM) i5-8300H CPU @ 2.30GHz 2.30 GHz
Installed RAM 32.0 GB (31.8 GB usable)
System type 64-bit operating system, x64-based processor
GPU Intel(R) UHD Graphics 630
Driver version 25.20.100.6576
Driver date 2/7/2019
DirectX Ver 12 (FL 12.1)