These workflows can be used as standalone utilities or the nodes can be inserted in your workflows
Multi-Upscale Nodes - Demo Workflows
The upscale nodes and templates were designed by the Comfyroll Team based on requirements provided by THM and other users on the AI Revolution discord sever.
The templates have the following use cases:
Batch upscaling, resizing and sharpening of images in a folder
Fine tuning upscaling using multiple upscalers
Hires Fix
List of Templates
Simple Batch Upscaling Demo
Multi Upscale Stack Demo
Both templates can be used with SDXL or SD1.5
Upscale Methods
Rescale method
This is the default method
The rescale factor is based on the size of the input image
e.g. a 512 x 512 image with rescale factor 2.0 will be rescaled to 1024 x 1024 after upscale models have been applied
Resize Method
With this method the aspect ratio is retained and the image is resized based on the resize_width
Example 1 - Multi-Upscale
Starting with a 512 x 512 image, if you do two 4x upscales with a 1.0 factor after the first upscale and 2.0 factor after the second upscale, then
the image size will upscale from 512 x 512 to 2048 x 2048
then rescale to 512 x 512
then upscale to 2048 x 2048
and then rescale to 1024 x 1024
Example using Upscale Image nodes:
Example using Upscale Stack nodes:
Example 2 - Replacing Existing Nodes
In this example upscale nodes in an existing workflow are replaced with the new nodes.
This is the before:
This is the after:
The rescale factors are always relative to the original image size.
After the first 1x upscale the rescale is set to 1.0 because no rescale is needed. After the second 4x upscale the recsale is set to 2.0. This is equivant to downsizing by 0.5 in the 'before' nodes. After the third x1 upscale there is no change in the size, but the final output needs to be 2x the original size, so the rescale factor is set to 2.0.
Nodes
CR Upscale Image
this node combines several existing nodes and adds some new features
supports both rescale and resize methods
CR Multi Upscale Stack
this is a data node that lists the upscale models and rescale factors that will be applied by CR Apply Multi Upscale
additional stacks can be chained together
a rescale factor can be configured for each upscale, these will be applied to the image size after each upscale
the last rescale_factor will determine the final size of the image
all rescale factors should normally be set to 1.0 excepting for the last one
advanced users can experiment with different values for the interim rescale factors
CR Apply Multi Upscale
a recursive loop applies each upscale and rescale based on the connected stack
this node uses the rescale method only
Templates
Simple Batch Upscaling Demo
simple design
SDXL or SD1.5
additional upscale nodes can be chained together
Multi Upscale Stack Demo
SDXL or SD1.5
the last rescale_factor in the stack will determine the final size of the image
the other factors determine the interim sizes between each upscale
additional stack nodes can be chained together if you need more than three upscales
Tips
You can add the image upscale nodes in any template
The nodes are particuarly good for hires fix
Upscale model stacks can be extended by adding more stacknodes chained to the first stack node.
Installation
Download the workflows
Install or update the following custom nodes
for Load Image Batch node
for the upscale nodes
Download some upscale models to get started, for example
You can find many more upscale models at these links
On first use
Select the upscale models
Place the images that you want to upload in a folder
Add the path to the folder in the Load Image Batch node
e.g. E:\Comfy Projects\image batch
it should contain at least one image file
Do a test run
Save a copy to use as your template
Troubleshooting
Please see our CivitAI article
Credits
LucianoCirino - for the original stack concept
THM - for assisting with requirements, testing the nodes, and for the cover picture
WAS - for the Image Resize code