Add Real-ESRGAN integration

[carson-katri]

A new "AI Upscaling" panel has been added. I also refactored the generator process a bit to allow for multiple "Intents" (the two current ones being PROMPT_TO_IMAGE and UPSCALE)

[NullSenseStudio]

Due to the stable diffusion branch change I've been getting ImportError: DLL load failed while importing cv2: The specified module could not be found. on line from stable_diffusion.ldm.generate import Generate while debugging, and oddly no exception is caught when starting Blender normally and just get Process closed unexpectedly.

For some reason Blender puts its python3.dll in Blender's root directory rather than in blender/3.3/python/bin. I've had no luck with changing the subprocess's cwd or modifying the PATH environment variable to help the subprocess find it.

So far only workarounds I've got are copying/symlink python3.dll into blender/3.3/python/bin, running the subprocess from a standard python runtime, or with some added code before that import:

if sys.platform == 'win32':
    from ctypes import WinDLL
    WinDLL(r"C:\Blender\stable\blender-3.3.0+lts.0759f671ce1f\python3.dll")

We should be able to get a proper path for other systems by modifying bpy.app.binary_path and sending to the subprocess as a command line argument.

[carson-katri]

@NullSenseStudio Thanks for catching this, I hadn’t gotten to Windows testing yet. Would you be able to implement that suggestion as a PR against this branch? Also I assume the DLL is at the root for blender installations in Program Files as well?

[NullSenseStudio]

I should have time to do that later today. I'll also double check if the solution works for the msi installer and on steam.

[NullSenseStudio]

PR has been made and can confirm that zip, msi, and steam versions all had the same issue and worked with the fix.

[carson-katri]

@NullSenseStudio Can you give this a try before I merge it?

[NullSenseStudio]

Here's some issues I ran into.

[carson-katri]

FYI, I added a "Full Precision" option to the upscaler but default to enabled. The precision options for the Dream Texture panel has been overhauled as well, and use an "Automatic" option now which can autodetect 16 series cards (due to invoke-ai enhancements).

[NullSenseStudio]

Nice addition. Looks like everything is working well now.

Did there used to be a strength option for upscaling or am I misremembering?

[NullSenseStudio]

All previous issues seem fixed.

[carson-katri]

Thanks for the reviews! I removed strength (for now) because it required two weight files to be downloaded which could be confusing, and it also is not available in 0.2.5.0 as far as I could tell (the dni_weight argument)?