基于未校准照片构造全景图的新方法

提出一种基于未校准的系列照片构造全景图纳新方法，该组照片可采用普通三脚架/数码相机在固定地点拍摄。采用普通三角架通过旋转角度拍摄的照片难以保证轴心一致性，可能出现图像扭曲、交叠和倾斜，照片之间可能有一定色差，因此，在图像的拼接和建立全景图方面难度大。文中采用特征匹配技术实现照片的拼接，通过照片的定位拼接、相邻照片颜色亮度的协调实现全景图的构建。该算法所生成的全景图效果好，计算速度快，巳得到实际应用。它可广泛应用于Web环境下的基于图像的虚拟场景构造等方面。     

Preservation of Photographs

Photogrophs ore susceptible to degradation (rom many sources. Attock on the imoge or bose can occur (rom residual processing chemicals. industrial atmospheric pollutants, contaminants (rom storage area construction materials or (rom the materials used (or mounting and containing the pictures. Degradation (rom poor processing can be detected with simple chemical tests. Until more becomes known about the many products normally associated with the preservation o( photographs, one should avoid using in the storage area fresh point, raw woods and volatile substances, and near or on the photographs avoid adhesives, plastics and poor quality papers. Regardless o( the preservation technique used it is help(ul to remember that the storage li(e of photographs can be extended by slowing down chemical activity. This can be achieved by care(ul control a( storage temperature and relative humidity (60 references).     

Walker Evans' American Photographs

Abstract

It is an article of faith among photographers and scholars that Walker Evans' American Photographs is a sequence of pictures rather than a simple collection or anthology; that is to say that the photographs should be looked at in the order in which they are given. Indeed the book is often spoken of as innovative and influential in precisely that respect (among others). Some years ago I set out to learn more about the origin of Evans' sequence in the context of a broader investigation of American Photographs.¹ That study (which remained unpublished) has now been superseded in many ways by Alan Trachtenberg's insightful discussion in the book Reading American Photographs, which appeared in 1989.² Nevertheless some of my original material remains useful and I offer it here largely intact, with only a small number of revisions and additions.     

Smith at Auschwitz: Research Product #5

Smith at Auschwitz: Research Product #5 is part of an ongoing series of projects that use photography and writing to address, often tangentially, the phenomenon of “dark tourism”. Here the author uses the form of documentary-fiction to consider the production, distribution and consumption of a public art project, staged in Poland, that ostensibly focused on Holocaust tourism in Eastern Europe. The author produces a “cultural biography” of the project that provides an account of: the relationship between it and the promotional value of research in a new English university; the performative nature of a photographic event at Auschwitz-Birkenau in 2005; and the project’s reception in the Polish city of Toruń in 2009. Smith at Auschwitz: Research Product #5 was originally performed, by four actors, at Belfast Exposed Gallery as part of the 2013 Belfast Photo Festival.     

The Extraction and Processing of Data from Bubble Chamber Photographs

If an ionizing particle passes through a super heated liquid boiling can take place on the ions created by the particle. These vapour bubbles are photographed under flash illumination and show up the track of the particle. By using two or more cameras the original space position of the track is calculated from measurements made on the different views. The present total rate of production of such photographs in the various high energy physics laboratories throughout the world is about ten million photographs per year. The various methods, in use today, for processing all this information are described and some comments made about possible future development.     

Photographs of the great game

Abstract

Since the discovery of photography, the camera has been a silent witness at countless theatres of war, presenting a story that is ofteh as objective as any written account. The conflicts in the Crimea and in India in the 1850s were the first to allow the photographer an opportunity to report publicly on the progress of a war. Given the developments in photographic techniques, however, the camera still lagged some distance behind the main action and was usually relegated to documneting the carnage left in the wake of a victorious force. Omar Khan's book tells many stories, but perhaps the most presistent and enthralling is the journey of the photographer from the back of the army, straught into the frontline in Afghanistan. The story is surprisingly emotional, as a thrilling narrative of tribal war and the history of the British Raj are interwoven into the lives of two relatively forgotten men who devoted theri lives to photography.     

The ‘Peccavi’ Photographs

Abstract

Among the holdings of the Asiatic Library of Bombay, there is a major album entitled Sind Photographs, which has become known to the initiated under the title ‘Peccavi Photographs’, in memory of a delicious political pun¹. All the photographs are portraits, with captions neatly inscribed. None is signed, but one bears the imprint ‘Photo by Capt. Houghton’, which was sufficient to provide researchers with an important clue as to their origin.     

Preparation of Stereoscopic Electron Microscope Photographs

The author discusses some of the problems involved in the mounting of stereoscopic electron microscope photographs taken on 35mm film.     

Photographs in the Janos Scholz Collection

Abstract

Janos Scholz (1903–1993), who was to become one of the great cellists of the twentieth century, began collecting when he was a child in Sopron, Hungary. After completing his studies at the Royal Hungarian Academy of Music, Scholz was named first cellist with the Budapest Symphony Orchestra. In 1932 he joined the Roth Quartet, and the following year he left Hungary to tour with the quartet in the United States. He became an American citizen in 1933 and made his home in New York until his death in 1993. Scholz began to collect prints and drawings in 1935 and over the next three decades he amassed an unrivalled collection ofItalian drawings. In keeping with the nature of his life as a musician, in which he shared his music through public recitals, Scholz announced in 1973 that he had decided to give his drawings to the Pierpont Morgan Library in New York. Soon afterwards he began a new collection, one that focused upon nineteenth-century European photographs on paper.     

Optical Processing of Bubble Chamber Photographs

Purely optical methods of spatial pulse width coding for coherent optical densitometry are described. The proposed coding scheme correlates the image intensity with the orientation of one edge of triangular or trapezoidal pulses. One encoding technique employs a contact screen similar to those used for half-tone printing. The image to be coded is copied through this contact screen onto hard-limiting film. This method is limited to the encoding of images with density distributions varying only slowly across the area of one pulse. A holographic encoding technique overcomes these drawbacks, utilizing the storage redundancy of holograms recorded with diffuse object beams. An array of identical holograms is reconstructed with a beam spatially modulated by the image transparency to be encoded. The array of reconstructed real images is recorded on hard-limiting film and renders a pulse-modulated version of the original image. The limiting conditions for the pulse size and the size of details in the image imposed by diffraction effects and speckle pattern are derived.     

Degradation of Gelatin in Historical Photographs

Abstract

In order to study age related changes in photographic gelatin toe analysed black-and-white roll film before and after accelerated ageing and samples of naturally aged glass plate negatives. Two-dimensional gel electrophoresis (2D-PACE) was used to separate collagen chains In the gelatin by isoelectric point (pi) and molecular weight. The results shoiv that the x-chatns break down into smaller fragments on ageing. Amino acid analysis ivas performed to examine the oxidative deterioration of gelatin. It shows that the amount of lysine decreases with age.     

牙齿形态图像的对比研究

在法庭科学中，人体鉴别主要采用下列四种技术：指纹鉴别、眼角膜纹识别、DNA技术和牙齿形态识别。指纹载体是综合性有机物，眼角膜是软组织，都不能长久保存，且我国未形成无前科人群的档案库，DNA技术虽精确，并已广泛应用，但费用昂贵而费时，因此这三种技术都有其不足之处。相比之下，牙齿形态鉴定法无上述缺点，效果甚佳。本文对此作了较详细的介绍。