Deep-learned variational auto-encoders (VAE) have shown remarkable capabilities for lossy image compression. These neural networks typically employ non-linear convolutional layers finding a compressible representation of the input image. Advanced techniques such as vector quantization, context-adaptive arithmetic coding and variable-rate compression been implemented in these auto-encoders. Nota...

Two experiments for evaluating psychophysical distortion metrics for JPEG-encoded images are described. The first is a threshold experiment, in which subjects determined the bit rate or level of distortion at which distortion was just noticeable. The second is a suprathreshold experiment in which subjects ranked image blocks according to perceived distortion. The results of these experiments we...

Image restoration algorithms are typically evaluated by some distortion measure (e.g. PSNR, SSIM) or by human opinion scores that directly quantify perceived perceptual quality. In this paper, we prove mathematically that distortion and perceptual quality are at odds with each other. Specifically, we study the optimal probability for discriminating the outputs of an image restoration algorithm ...

Optical imaging systems often suffer from distortion artifacts which impose important limitations on the direct interpretation of the images. It is possible to correct for these aberrations through image processing, but due to their calculation-intensive nature, the required corrections are typically performed offline. However, with image-based applications that operate interactively, real-time...

This thesis describes a novel video mosaicing method which is capable of generating a geometric distortion-free mosaic image. Video mosaicing, which stitches partial images of a target into a larger image called a mosaic image, has been used to obtain high resolution images of documents. Generally, mosaic images are prone to two types of geometric distortions: perspective distortion which appea...

In this paper, we proposed a new stratified method for correcting the radial distortion of a strong wide-angle lens using a single image. The key idea is to use a 3D concave calibration rig with three planar patterns aligned orthogonally with each other. The parallelism of the line patterns, orthogonality and concavity of the rig enable us to deal with the distortion of the entire image that is...

We investigate different allocation problem in mobile adhoc networks. The objective is to minimize the power consumption and end-to-end distortion when transmitting images. Therefore, we use progressive image coding in combination with unequal erasure protection. We investigate two different scenarios, independent packet loss events and path loss events. For both cases, the expected distortion ...