Subjective Picture Research Articles

Hieronymus van der Mij als historie- en genreschilder

Hieronymus van der Mij als historie- en genreschilder

A New Architecture for Adaptive Intrafield Transform Compression of NTSC Composite Video Signal

In orthogonal transform coding of NTSC video signal, the data are processed in blocks. Processing a block of data that is maximally correlated leads to larger compression. This correspondence describes a new architecture for arranging the pixels in a block that yields higher correlation than the adjacent pixel blocks. The data are processed using adaptive, intrafield, discrete cosine transform, variable bit allocation coding. In subjective tests good quality pictures were obtained for an average of about 2 bits/pel for intrafield processing.

On the status of stability of interconnected systems

In the present paper we report on the status of stability of complex dynamical systems. We consider those systems which may be viewed as an interconnection of lower order subsystems. We emphasize those types of results which are phrased in terms of the stability properties of the subsystems and in terms of the qualitative properties of the system interconnecting structure. We consider both Lyapunov stability and input-output stability results. In our presentation, we concentrate on selected sample results and we show how some of these results are related. We then use these sample results to identify modifications, extensions, generalizations, and applications. In this way, we are able to provide a reasonably good picture of the entire subject on hand.

Subjective assessment of bandwidth limitation of the 625-line television luminance signal

Results are given of a study to determine the relationship between subjective picture quality and bandwidth for the 625-line television luminance signal for a range of picture material. They indicate that only a small improvement in still picture quality is to be gained by increasing pulse bandwidth beyond about 3.5 MHz. Conversely, a rapid diminution in quality results when pulse bandwidth falls below about 2 MHz. The filters used in the study were designed to have a near-optimum roll-off characteristic and to be relatively cheap and easily implemented.

On the status of stability of interconnected systems

In the present paper we report on the status of stability of complex dynamical systems. We consider those systems which may be viewed as an interconnection of lower order subsystems. We emphasize those types of results which are phrased in terms of the stability properties of the subsystems and in terms of the qualitative-properties of the system interconnecting structure. We consider both Lyapunov stability and input-output stability results. In our presentation, we concentrate on selected sample results and we show how some of these results are related. We then use these sample results to identify modifications, extensions, generalizations, and applications. In this way, we are able to provide a reasonably good picture of the entire subject on hand.

On the status of stability of interconnected systems

In the present paper we report on the status of stability of complex dynamical systems. We consider those systems which may be viewed as an interconnection of lower order subsystems. We emphasize those types of results which are phrased in terms of the stability properties of the subsystems and in terms of the qualitative properties of the system interconnecting structure. We consider both Lyapunov stability and input-output stability results. In our presentation, we concentrate on selected sample results and we show how some of these results are related. We then use these sample results to identify modifications, extensions, generalizations, and applications. In this way, we are able to provide a reasonably good picture of the entire subject on hand.

Extralinguistic control of language comprehension and production in the nonfluent child

The study investigated (1) the developmental progression postulated to exist between comprehension and production of sentences having the same grammatical form, and (2) the effects of syntactic, semantic, and extralinguistic variables on comprehension and production in nursery-school children. Comprehension trials required choices among four puzzle piece alternatives for which (a) both subject and object pieces differed (Phase I) or (b) only grammatical subject pictures differed (Phase II). During production trials children were asked to label preconstructed puzzles. Results indicated the comprehension-production relationship to vary as a function of age, sentence prepositions, and phases. Differential effects of semantic and extralinguistic variables during comprehension were found primarily for the youngest children, suggesting that logical relations among agent-actor-object were not sole controllers of language comprehension. Nonsyntactic control of production responses was not found.

Orienting task effects on the recognition of humorous pictures in amnesic and normal subjects

Abstract Amnesic and control subjects were variously asked to remember, describe, and spot differences between similar versions of captionless cartoon pictures. There were three series, presented individually on consecutive days. Each series contained pictures differing in their experimenter-rated humour. Amnesics were tested at one and controls at 14 days to equate their recognition performance. In general the memory of both groups was similarly improved or impaired after respectively describing or spotting differences between pictures. The mnemonic advantage of humorous pictures was similar in extent for both groups and was similarly affected by the orienting tasks. It was also shown that the humour ratings of the two groups were closely comparable and that their memory was exceptional for pictures rated as funniest. Results are discussed in terms of possible encoding and activation problems in amnesics.

Digital Comb-Filter Demodulation of PAL Color-Television Signals

Digital comb filter devices with one or two line memories or with picture memories for the demodulation of PAL color TV signals are presented and compared with respect to their effects on subjective picture quality. The color video signals are assumed to be sampled at four times the color subcarrier frequency, the sampling frequency adopting a definite phase with respect to the color subcarrier. Methods are discussed which are able to stabilize the frame by frame changing of the sampling patterns in the case of comb-filter devices containing only one line memory. It is shown that comb-filters with two line memories and with picture memories have inherent stability and that the decoder with a frame delay guarantees at the expense of a sophisticated hardware full resolution in non-changing parts of a picture sequence.

Subjective Impairmnt Units in Relation With Oscilloscope Graticules for Evaluating Short-Time Linear Waveform Distortion of the Luminance Signal in 525-Line Television

Objective ratings (for example, the K-rating) for waveform distortion are assessed customarily by using oscilloscope graticules. They are based on subjective evaluations of television picture impairments. As the impairment unit (imp) is a unit which expresses subjective impairments quatitatively, it is used here as a means to check whether the graticules proposed for the assessment of short-time linear distortion of the luminance signal in television in North America comply with the principle that a given rating factor should correspond to a single value of subjective impairment. This is accomplished by converting to imps the results of published North American evaluations of subjective picture quality and utilizing a computer, in connection with a specially devised algorithm, to derive the imp value corresponding to any given point on a rating outline of the graticules examined. In addition, imp-to-rating relations are derived where feasible.

Television measurements through psychophysics to subjective picture quality

The most important property of a television system is the quality of the received picture as judged by the user. An explanation is offered of the way in which human beings quantify picture quality and the apparent magnitude of picture impairments. Although the explanation is speculative, it is hoped it will prove intuitively attractive, and will assist both the interpretation of the results of visual subjective studies and their application in terms of objective measurements. The psychological scale of apparent magnitude turns out to be also the scale along which co-existing impairments may be simply summed to determine their total effect. It is thus closely related to the IMP scale which has already found practical application.

The Genetic Approach to Human Disease,

According to the author, this book is designed to show what the clinical application of genetic principles can accomplish. In the introductory chapters, the reader is introduced to the contemporary working claṡsification of medical genetics: chromosomal disorders, disorders with Mendelian patterns of inheritance, and polygenic disorders. There is an abbreviated chapter on biochemical errors of inheritance. This is followed by chapters on environmental influences on the fetus, genetic evaluation, prenatal diagnosis, genetic evaluation and counseling, roles of ancillary personnel in clinical genetics, therapy of genetic disorders, pharmacogenetics, ethical, moral, and legal aspects, and finally a description of a regional genetic counseling program. The chapters on pharmacogenetics, biochemical disorders, and ethical, moral, and legal aspects are very short, and hardly can present an adequate picture of this complicated subject. The final chapter describing a regional genetic counseling program seems not adequately relevant in this textbook. In fairness to the author, it

Subjective quality of television pictures impaired by linear waveform distortion

Existing subjective results relating to the effect of undistorted echo in television have been applied to determine the psychophysical relationship between subjective picture quality and the objective measure of linear waveform distortion, termed the `K-rating?. Values of the coefficients G and KM are given, which, starting with a known value of K, permit estimates to be made of mean picture quality and of subjective impairment in summable (imp) units.

Modified slant and modified slant Haar transforms for image data compression

Transform image processing is done in nonoverlapping blocks and a block of (4 × 4) or a (8 × 8) subpicture size is reasonable in terms of both mean-square error and subjective picture quality. It is therefore desirable to search for a fast transform which is efficient for data of small sequence length. This paper presents a modified slant and a modified slant Haar transform. Computational operations are increased by 2 additions and 4 multiplications only as compared to conventional slant and slant Haar transforms. Performance evaluation based on a first-order stationary Markov process signal such as variance distribution, mean-square error estimate due to scalar Wiener filtering of signal corrupted by white noise and decorrelation property establish the superiority of the transforms. Comparative study of results on a monochrome picture are encouraging.

ESP3: A Language for Pattern Description and a System for Pattern Recognition

Extended Snobol picture pattern processor (ESP3) is a programming language and pattern recognition system which was designed for generating, recognizing, and manipulating two-dimensional line drawings. An ESP3 picture pattern describes a class of line drawings just as a Snobol pattern describes a class of strings. During pattern matching, a subject picture is searched for the occurrence of a sub-picture which matches a given picture pattern. The search of the subject picture is ordered left-to-right and top-to-bottom, and the search program uses scanner guidance information found in the picture pattern to limit the area of the subject picture to be searched. An experimental implementation of ESP3 has been developed to test the feasibility of the system. This paper describes the ESP3 picture patterns, the pattern matching operation, and the experimental implementation of ESP <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> .

Figurative 'Polarized Light Paintings': Static and Kinetic Types

While teaching general courses in the history and philosophy of physics, wherein the effects of science on society were discussed at length, I began to appreciate various ways in which aspects of physics had affected the visual arts. Later, in order to pursue this idea in greater depth, several students and I decided to make a study of the use of polarized light and to attempt to develop a technique for the construction of polarized light pictures. We were particularly interested in both static and kinetic pictures of figurative subjects. (Several similar techniques for making kinetic pictures have been discussed in Leonardo [1, 2, 3].) We believe the technique we have devised will be of interest. The pictures obtainable (we call them 'polarized light paintings') remind one of stained glass windows (Fig. 1, cf. color plate). It is well known that, when a piece of sheet birefringent (doubly refracting) material is sandwiched between two polarizers (e.g. two pieces of sheet polarizing material, such as that produced by the Polaroid Co., Cambridge, Mass., U.S.A.), striking color effects are produced when ordinary white light is passed through the sandwich [4, 5]. Furthermore, when one of the polarizers is rotated through 360?, a particular color will change to its complement twice during this rotation. Additional color effects can be produced when different thicknesses or several layers of a birefringent material are used (such as ordinary transparent cellulose tape, cellophane or certain other plastics), when the angle of the surface of these materials is varied with respect to the surfaces of the polarizers and when their birefringent property is altered, for example by heat or chemical treatment. The colors produced also generally vary with the type of light source used. Thus, since the wavelength composition of sunlight and of light from fluorescent and incandescent lamps are different, the amounts of light at each wavelength transmitted by the sandwich are different, leading to the production of different colors.

Exploiting Art: The Pictures in Bernard Shaw's Plays

THROUGHOUT A LONG LIFETIME Bernard Shaw remained intensely interested in the visual arts, and exploited his familiarity with English and Continental art in his plays. A new dimension emerges when Shavian drama is examined through this lens. A century ago, when English painting was still suffering from the blight of the sentimental academic subject picture, and Ireland was culturally at least a generation behind, the young Bernard Shaw could have been guaranteed a surfeit of subject paintings in Dublin. When he left for London at twenty, in 1876, the art which English galleries found saleable, despite the inroads of PreRaphaelitism, was much the same. Victorian religiosity and humanitarianist idealism encouraged production of the overloaded anecdote or genteel landscape, and Shaw's early dramatic settings could not help but be influenced, even when he intended to use a scene ironically, by what English eyes were accustomed to encountering in art.

The Autonomy of Idiopathic Erosive Proctitis

HIGH ON the list of badly underpublicized diseases of the gastrointestinal tract stands idiopathic erosive proctitis. Its poor press is explained by the usual habit of lumping it with common ulcerative colitis. The fact: it is an entirely different disease, no more like ulcerative colitis than amebic colitis. The Subjective Picture Idiopathic erosive proctitis usually begins during the third or fourth decade. Most patients are women, although I am unable to suggest in what proportion. To the patient, the onset seems sudden. The patient feels well but all at once sees red blood on stool or toilet tissue. Rectal bleeding is the main manifestation at the beginning and throughout the course of the illness. It tends to persist daily for many weeks or months, sometimes with brief periods of spontaneous improvement, but in most patients it shows a doggedness that leads to chronic discouragement among all concerned. The blood is

Opinion-rating model applied to television-transmission-system studies

The means by which a recently described opinion-rating model may be applied to the performance of television transmission systems are outlined. The starting point is the statistical description of the objective magnitude of each distinct type of impairment arising in the system. For each type, the relationship between objective magnitude and picture quality must be known or estimated. Three distinct continua are invoked for the model, each having a functional relationship with the ‘psychological scale’ of opinion regarding the picture quality. The first, the t scale, may be regarded as the direct scale of opinion level; it is used to interpret the results of laboratory experiments and to express system performance meaningfully. The second scale, the T scale, is useful because the variability of observers&apos; standards results in a near-normal distribution on it. The third scale, the J scale, is one on which the effects of different coexisting impairments may be arithmetically summed; the scale resembles the existing I, or ‘imp’ scale, but, whereas the I scale is based on the mean opinion score, the J scale may be used to express the probability distribution of opinions as well as the average value. By way of example, the model is applied to fading interference in broadcasting, and to the measured performance of a long point-to-point transmission chain in the United Kingdom, involving 5 main links, a rebroadcasting link, and several lesser components. An interesting conclusion of the latter study is that the variation in subjective picture quality resulting from the combined effects of all the varying transmission impairments was unimportant. Although viewers could have noted that the most prominent impairment was not always the same, variations in opinion level would have been almost entirely due to the variability of the viewers themselves.

Milk intolerance after gastrectomy.

The authors compared by X-ray the passage of a milk containing lactose with that of a lactose-free milk in subjects after partial gastrectomy who, after operation, developed milk intolerance. In the X-ray picture of subjects with a lower mucosal lactase level, typical differences between the two passages are found. The main difference is that the gastric stump is unable to slow down the milk supply sufficiently to the small intestine and, thus, as a result of the lower mucosal lactase level, the relative lactase insufficiency becomes manifest. During the fractionated administration of the lactose containing milk mixture the X-ray intolerance changes disappear. When the X-ray pictures after both milk mixtures do not differ, milk intolerance has obviously another cause than lactose maldigestion.