install SDXL "fixed" VAE (#4020)

## What type of PR is this? (check all applicable)

- [ ] Refactor
- [ ] Feature
- [ ] Bug Fix
- [ X] Optimization
- [ ] Documentation Update
- [ ] Community Node Submission


## Have you discussed this change with the InvokeAI team?
- [ X] Yes
- [ ] No, because:

      
## Have you updated all relevant documentation?
- [ ] Yes
- [X ] No


## Description

This PR causes the installer to install, by default, the fine-tuned
SDXL-1.0 VAE located at
https://huggingface.co/madebyollin/sdxl-vae-fp16-fix.

Although this VAE is supposed to run at fp16 resolution, currently it
only works in InvokeAI at fp32. However, because it is a fine tune, it
may have fewer of the watermark-related artifacts that we see with the
SDXL-1.0 VAE.

invokeai/backend/install/model_install_backend.py

@@ -154,7 +154,7 @@ class ModelInstall(object):
         models = set()
         for key, value in self.datasets.items():
             name,base,model_type = ModelManager.parse_key(key)
-            if all_models or model_type==ModelType.Main:
+            if all_models or model_type in [ModelType.Main, ModelType.Vae]:
                 models.add(key)
         return models
 

invokeai/backend/model_management/model_probe.py

@@ -416,7 +416,14 @@ class PipelineFolderProbe(FolderProbeBase):
 
 class VaeFolderProbe(FolderProbeBase):
     def get_base_type(self)->BaseModelType:
-        return BaseModelType.StableDiffusion1
+        config_file = self.folder_path / 'config.json'
+        if not config_file.exists():
+            raise InvalidModelException(f"Cannot determine base type for {self.folder_path}")
+        with open(config_file,'r') as file:
+            config = json.load(file)
+        return BaseModelType.StableDiffusionXL \
+            if config.get('scaling_factor',0)==0.13025 and config.get('sample_size') in [512, 1024] \
+            else BaseModelType.StableDiffusion1
 
 class TextualInversionFolderProbe(FolderProbeBase):
     def get_format(self)->str:

invokeai/configs/INITIAL_MODELS.yaml

@@ -24,6 +24,14 @@ sdxl-refiner/main/stable-diffusion-xl-refiner-1-0:
    description: Stable Diffusion XL refiner model (12 GB)
    repo_id: stabilityai/stable-diffusion-xl-refiner-1.0
    recommended: False
+sdxl-refiner/main/stable-diffusion-xl-refiner-1-0:
+   description: Stable Diffusion XL refiner model (12 GB)
+   repo_id: stabilityai/stable-diffusion-xl-refiner-1.0
+   recommended: false
+sdxl/vae/sdxl-1-0-vae-fix:
+   description: Fine tuned version of the SDXL-1.0 VAE
+   repo_id: madebyollin/sdxl-vae-fp16-fix
+   recommended: true
 sd-1/main/Analog-Diffusion:
    description: An SD-1.5 model trained on diverse analog photographs (2.13 GB)
    repo_id: wavymulder/Analog-Diffusion

scripts/probe-model.py

@@ -0,0 +1,11 @@
+#!/bin/env python
+
+import sys
+from pathlib import Path
+from invokeai.backend.model_management.model_probe import ModelProbe
+
+info = ModelProbe().probe(Path(sys.argv[1]))
+print(info)
+
+      
+