A noticeable absence

A 3D Perceptual Metric using Just-Noticeable-Difference

In multimedia applications, it is essential to distribute resources efficiently among different types of data in order to optimize overall quality. We propose a perceptual metric using Just-Noticeable-Difference (JND) to identify redundant mesh data so that available bandwidth can be allocated to improve texture resolution. Evaluation of perceptual impact during runtime is based on statistics i...

Protecting identity documents with a just noticeable microstructure

The development of plastic card printers has led to the widespread use of identity documents printed on plastic cards, such as ID cards, driving licenses and access key cards. This paper presents a new security feature based on a technique for embedding a personalized microstructure into a photograph. This microstructure takes the form of a bitmap pattern embedded into the original photograph a...

Chronic, Progressive Back Pain, Fever and a Noticeable Paravertebral Mass

A 46-year-old woman presented with an 8-month history of fever, lumbar pain, and a slowly growing right paravertebral mass. She reported regular consumption of unpasteurized goat cheese. The physical examination revealed a fluctuant right paravertebral mass and marked pain on palpation over the lumbar spine at the L3-L4 level. A computed tomography (CT) scan of the spine revealed erosions of th...

A Just-Noticeable-Distortion Based Perceptually Lossless Image Compression Codec

Noticeable, troublesome and objectionable limits of blur

We investigated limits at which induced blur becomes noticeable, troublesome and objectionable. We used 15 cyclopleged subjects, a Badal optometer with lines of three high contrast letters as targets, 3-6 mm artificial pupils, and 0.0-0.7 logMAR letter sizes. For 0.0 logMAR size, mean "noticeable" blur limits were +/-0.33D, +/-0.30D and +/-0.28D at 3 mm, 4 mm and 6 mm, respectively, but increas...