MewZoom

A family of open-source super-resolution models with purrfect pixels. Pre-trained on a diverse set of images and fine-tuned with an adversarial network for exceptional realism, Mew Zoom upscales your images by 2X, 3X, 4X, or 8X the original size while identifying and removing blur, noise, and artifacts.

Key Features

• Fast and scalable: MewZoom incorporates parameter-efficiency into the architecture requiring less parameters than models with similar performance.

• Multiple architectures: Choose from the parameter-efficient TrunkNet architecture or the larger UNet architecture with multi-scale embeddings.

• Ultra clarity: MewZoom is explicitly trained to identify and remove blur, noise, and compression artifacts using a auxillary training objective.

• Full RGB: MewZoom operates within the full RGB color domain enhancing both luminance and chrominance for the best possible image quality.

Web Demo

Check out the MewZoom Web UI for upscaling images in the browser. Inference happens on your device and your data never leaves the browser. Note that, due to the limitations of Web Assembly, only CPU with max 4GB of memory is supported.

Code Repository

The training and inference code is available at https://github.com/andrewdalpino/MewZoom.

Pretrained Models

The latest pretrained models are available on HuggingFace Hub. They use the newer mewzoom library for inference.

Name	Upscale	Architecture	Channels	Layers	Parameters	Library Version
andrewdalpino/MewZoom-V1-2X-Unet	2X	UNet	48/96/192/384	4/4/4/4	32M	1.x
andrewdalpino/MewZoom-V1-2X	2X	TrunkNet	48	64	5.3M	1.x
andrewdalpino/MewZoom-V1-4X-Unet	4X	UNet	96/192/384/768	4/4/4/4	128M	1.x
andrewdalpino/MewZoom-V1-4X	4X	TrunkNet	96	64	21M	1.x

Legacy Models

The following legacy pretrained models are also available on HuggingFace Hub. Note that legacy models use the ultrazoom library for inference.

Name	Upscale	Channels	Layers	Parameters	Control Modules	Library Version
andrewdalpino/MewZoom-V0-2X	2X	48	20	1.8M	No	0.1.x
andrewdalpino/MewZoom-V0-2X-Ctrl	2X	48	20	1.8M	Yes	0.2.x
andrewdalpino/MewZoom-V0-3X	3X	54	30	3.5M	No	0.1.x
andrewdalpino/MewZoom-V0-3X-Ctrl	3X	54	30	3.5M	Yes	0.2.x
andrewdalpino/MewZoom-V0-4X	4X	96	40	14M	No	0.1.x
andrewdalpino/MewZoom-V0-4X-Ctrl	4X	96	40	14M	Yes	0.2.x

Examples

To load pretrained weights and start upscaling your images, getting started is as simple as in the examples below.

PyTorch

In this example we'll use HuggingFace Hub to download the pretrained model weights and then run inference using the Python mewzoom library which utilizes PyTorch under the hood. First, you'll need the mewzoom package installed into your project. We'll also need the torchvision library to do some basic image preprocessing. We recommend using a virtual environment to make package management easier.

pip install mewzoom~=1.0.0 torchvision

Then, load the weights from HuggingFace Hub using the from_pretrained() method, load and convert the input image to a tensor using Torch Vision, upscale the image using the model, and then display the upscaled image.

import torch

from torchvision.io import decode_image, ImageReadMode
from torchvision.transforms.v2 import ToDtype, ToPILImage

from mewzoom.model import MewZoom


model_name = "andrewdalpino/MewZoom-V1-2X-Unet"
image_path = "./bird.png"

model = MewZoom.from_pretrained(model_name)

image_to_tensor = ToDtype(torch.float32, scale=True)
tensor_to_pil = ToPILImage()

image = decode_image(image_path, mode=ImageReadMode.RGB)

x = image_to_tensor(image).unsqueeze(0)

y_pred = model.upscale(x)

pil_image = tensor_to_pil(y_pred.squeeze(0))

pil_image.show()

ONNX Runtime

If you prefer to run the models via an ONNX runtime then you can manually download the ONNX model from the model's repository on HuggingFace Hub and then load the graph into your preferred ONNX-compatible inference engine. In Python, you'll first need to install the onnxruntime, numpy, and pillow dependencies into your project using your favorite package manager.

pip install onnxruntime numpy pillow

Then, load the weights, process the input image so that it's compatible with the ONNX graph, upscale the image, and then display it.

import numpy as np
import onnxruntime as ort

from PIL import Image

model_path = "./model.onnx"
image_path = "./bird.png"

session = ort.InferenceSession(model_path, providers=["CPUExecutionProvider"])

image = Image.open(image_path).convert("RGB")

image_array = np.array(image, dtype=np.float32) / 255.0  # Normalize to [0, 1]

# Convert from (H, W, C) to (1, C, H, W)
input_tensor = np.transpose(image_array, (2, 0, 1))
input_tensor = np.expand_dims(input_tensor, axis=0)

outputs = session.run(None, {"x": input_tensor})

output_tensor = outputs[0][0]  # Remove batch dimension

output_array = np.transpose(output_tensor, (1, 2, 0))  # (C, H, W) -> (H, W, C)
output_array = np.clip(output_array, 0.0, 1.0)

output_image = (output_array * 255).astype(np.uint8)

result = Image.fromarray(output_image, "RGB")

result.show()

Comparisons

View at full resolution for best results. More comparisons can be found here.

This comparison demonstrates the strength of the enhancements (deblurring, denoising, and deartifacting) applied to the upscaled image.

This comparison demonstrates the individual enhancements applied in isolation.

References

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