SINCO: A Novel structural regularizer for image compression
using implicit neural representations
Harry Gao∗, Weijie Gan∗, Zhixin Sun, and Ulugbek S. Kamilov
∗These authors contributed equally to this work.
Computational Imaging Group, Washington University in St. Louis, MO 63130, USA
{harrygao, weijie.gan, zhixin.sun, kamilov}@wustl.edu
Abstract
Implicit neural representations (INR) have been recently proposed as deep learning (DL) based solutions for image
compression. An image can be compressed by training an INR model with fewer weights than the number of image
pixels to map the coordinates of the image to corresponding pixel values. While traditional training approaches for
INRs are based on enforcing pixel-wise image consistency, we propose to further improve image quality by using a
new structural regularizer. We present structural regularizationfor INR compression (SINCO) as a novel INR method
for image compression. SINCO imposes structural consistency of the compressed images to the groundtruth by using
a segmentation network to penalize the discrepancy of segmentation masks predicted from compressed images. We
validate SINCO on brain MRI images by showing that it can achieve better performance than some recent INR
methods.
1 Introduction
Image compression is an important step for enabling efficient transmission and storage of images in many applica-
tions. It is widely used in biomedical imaging due to the high-dimensional nature of data. While traditional image
compression methods are based on fixed image transforms [1,2], deep learning (DL) has recently emerged as a power-
ful data-driven alternative. The majority of DL-based compression methods are based on training autoencoders to be
invertible mappings from image pixels to quantized latent representations [3–5].
In this work, we seek an alternative to the autoencoder-based compression methods by focusing on a recent paradigm
using implicit neural representations (INRs). INR refers to a class of DL techniques that seek to learn a mapping
from input coordinates (e.g., (x, y)) to the corresponding physical quantities (e.g., density at (x, y)) by using a multi-
layer perceptron (MLP) [6–10]. Recent studies have shown the potential of INR in image compression [11–15]. The
key idea behind INR based compression is to train a MLP to represent an image and consider the weights of the
trained model as the compressed data. One can then reconstruct the image by evaluating the pre-trained MLP on the
desired pixel locations. The traditional training strategy for image compression using INRs seeks to enforce image
consistency between predicted and groundtruth image pixels. On the other hand, it is well-known that image quality
can be improved by infusing prior knowledge on the desired images [16,17]. Based on this observation, we propose
Structural regularIzatioNfor INR COmpression (SINCO) as new method for improving INR-based image compression
using a new structural regularizer. Our structural regularizer seeks to improve the Dice score between the groundtruth
segmentation maps and those obtained from the INR compressed image using a pre-trained segmentation network.
We validate SINCO on brain MR images by showing that it can lead to significant improvements over the traditional
INR-based image compression methods. We show that the combination of the traditional image-consistency loss and
our structural regularizer enables SINCO to learn an INR that can better preserve desired image features.
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arXiv:2210.14974v1 [eess.IV] 26 Oct 2022