Abstract-A new method of farthest point strategy (FPS) for progressive image acquisition-an acquisition process that enables an approximation of the whole image at each sampling stage-is presented. Its main advantage is in retaining its uniformity with the increased density, providing efficient means for sparse image sampling and display. In contrast to previously presented stochastic approaches, the FPS guarantees the uniformity in a deterministic min-max sense. Within this uniformity criterion, the sampling points are irregularly spaced, exhibiting anti-aliasing properties comparable to those characteristic of the best available method (Poisson disk). A straightforward modification of the FPS yields an image-dependent adaptive sampling scheme. An efficient O(N log N) algorithm for both versions is introduced, and several applications of the FPS are discussed.

No abstract

Abstract-A new method of farthest point strategy (FPS) for progressive image acquisition-an acquisition process that enables an approximation of the whole image at each sampling stage-is presented. Its main advantage is in retaining its uniformity with the increased density, providing efficient means for sparse image sampling and display. In contrast to previously presented stochastic approaches, the FPS guarantees the uniformity in a deterministic min-max sense. Within this uniformity criterion, the sampling points are irregularly spaced, exhibiting anti-aliasing properties comparable to those characteristic of the best available method (Poisson disk). A straightforward modification of the FPS yields an image-dependent adaptive sampling scheme. An efficient O(N log N) algorithm for both versions is introduced, and several applications of the FPS are discussed.

Recent studies of cortical simple cell function suggest that the primitives of image representation in vision have a wavelet form similar to Gabor elementary functions (EF's). It is shown that textures and fully-textured images can be practically decomposed into, and synthesized from, a finite set of EF's. Textured-images can be synthesized from a set of EF's using image coefficient library. Alternatively, texturing of contoured (cartoon-like) images is analogous to adding chromaticity information to contoured images. A method for texture discrimination and image segmentation using local features based on the Gabor approach is introduced. Features related to the EF's parameters provide efficient means for texture discrimination and classification. This method is invariant under rotation and translation. The performance of the classification appears to be robust with respect to noisy conditions. The results show an insensitivity of the discrimination to relatively high noise levels, comparable to the performances of the human observer.

\s=b\The long-term results of myringoplasty in children, including closure of perforation and hearing improvement, were reviewed in relation to age, condition of the operated-on ear, and condition of the untreated ear. The overall success rate in 155 operations evaluated one year postoperatively was 79%. Children in the 5-to 8-year-old age group had a success rate comparable to that of older (9-to 12-year-old) children (77.7% vs 80.4%). Where graft failure occurred, it was usually within one year of surgery. The outcome of surgery could not be related to the presence or absence of chronic otitis media in the untreated ear, the status of the operated-on ear (whether dry or discharging), or the performance of adenoidectomy before myringoplasty. Results of postoperative hearing, analyzed by calculating the postoperative air-bone gap and by speech audiometry, were similar in the two age groups. It is concluded that myringoplasty has a good chance of success in children, regardless of age.The surgical management of chron¬ ic suppurative otitis media in children remains a controversial sub¬ ject. Most otologie surgeons believe that the results of tympanoplastic surgery to repair a tympanic mem¬ brane perforation are less satisfacto¬ ry in children than in adults, attribut¬ ing their findings both to the higher incidence of upper respiratory tract infections in children leading to acute otitis media or otitis media with effu¬ sion (OME), and to the unpredictabili¬ ty of their eustachian tube function.1The optimum age for myringoplasty is considered to be anywhere from 3 years to puberty.2"6 While for some children, closure of the tympanic membrane appears to be contraindi¬ cated, for others it is a necessity because of hearing problems and recurrent infection. This retrospective study of myrin¬ goplasty in children was undertaken to determine whether surgery in chil¬ dren aged 5 to 8 years is less success¬ ful in terms of perforation closure and hearing gain than in older children, and to identify which, if any, preoper¬ ative parameter might predict the outcome of surgery. PATIENTS AND METHODSThe charts of 172 children, aged 5 to 12 years, who underwent myringoplasty between 1974 and 1985 in Kaplan Hospital (Rehovot, Israel) were reviewed. All the children had a central perforation involv¬ ing only the pars tensa of the tympanic membrane, without cholesteatoma. All children aged 5 years or older who were seen in our clinic and in whom perforation did not close spontaneously for at least one year of follow-up underwent surgery. No further preselection of surgical candidates was made. Data were available from 155 children undergoing 172 operations, in¬ cluding 17 revision procedures.In all patients, the postauricular approach was used and temporal fascia was used as graft material. The underlay technique was used in 96% of patients and the overlay method (lateral graft place¬ ment) in the rest. The patients were rou¬ tinely discharged on the morning following surgery. Prophylactic antibiotics were not given before or aft...