Video is an electronic medium for the recording, playback and display of moving visual media. Video was first developed for mechanical television systems, which were replaced by cathode ray tube systems which were replaced by flat panel displays of several types. Video systems vary in display resolution, aspect ratio, refresh rate, color capabilities and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcast, magnetic tape, optical discs, computer files, network streaming. Video technology was first developed for mechanical television systems, which were replaced by cathode ray tube television systems, but several new technologies for video display devices have since been invented. Video was exclusively a live technology. Charles Ginsburg led an Ampex research team developing one of the first practical video tape recorder. In 1951 the first video tape recorder captured live images from television cameras by converting the camera's electrical impulses and saving the information onto magnetic video tape.

Video recorders were sold for US$50,000 in 1956, videotapes cost US$300 per one-hour reel. However, prices dropped over the years; the use of digital techniques in video created digital video. It could not compete with analog video, due to early digital uncompressed video requiring impractically high bitrates. Practical digital video was made possible with discrete cosine transform coding, a lossy compression process developed in the early 1970s. DCT coding was adapted into motion-compensated DCT video compression in the late 1980s, starting with H.261, the first practical digital video coding standard. Digital video was capable of higher quality and much lower cost than earlier analog technology. After the invention of the DVD in 1997, the Blu-ray Disc in 2006, sales of videotape and recording equipment plummeted. Advances in computer technology allows inexpensive personal computers and smartphones to capture, store and transmit digital video, further reducing the cost of video production, allowing program-makers and broadcasters to move to tapeless production.

The advent of digital broadcasting and the subsequent digital television transition is in the process of relegating analog video to the status of a legacy technology in most parts of the world. As of 2015, with the increasing use of high-resolution video cameras with improved dynamic range and color gamuts, high-dynamic-range digital intermediate data formats with improved color depth, modern digital video technology is converging with digital film technology. Frame rate, the number of still pictures per unit of time of video, ranges from six or eight frames per second for old mechanical cameras to 120 or more frames per second for new professional cameras. PAL standards and SECAM specify 25 frame/s. Film is shot at the slower frame rate of 24 frames per second, which complicates the process of transferring a cinematic motion picture to video; the minimum frame rate to achieve a comfortable illusion of a moving image is about sixteen frames per second. Video can be progressive. In progressive scan systems, each refresh period updates all scan lines in each frame in sequence.

When displaying a natively progressive broadcast or recorded signal, the result is optimum spatial resolution of both the stationary and moving parts of the image. Interlacing was invented as a way to reduce flicker in early mechanical and CRT video displays without increasing the number of complete frames per second. Interlacing retains detail while requiring lower bandwidth compared to progressive scanning. In interlaced video, the horizontal scan lines of each complete frame are treated as if numbered consecutively, captured as two fields: an odd field consisting of the odd-numbered lines and an field consisting of the even-numbered lines. Analog display devices reproduce each frame doubling the frame rate as far as perceptible overall flicker is concerned; when the image capture device acquires the fields one at a time, rather than dividing up a complete frame after it is captured, the frame rate for motion is doubled as well, resulting in smoother, more lifelike reproduction of moving parts of the image when viewed on an interlaced CRT display.

NTSC, PAL and SECAM are interlaced formats. Abbreviated video resolution specifications include an i to indicate interlacing. For example, PAL video format is described as 576i50, where 576 indicates the total number of horizontal scan lines, i indicates interlacing, 50 indicates 50 fields per second; when displaying a natively interlaced signal on a progressive scan device, overall spatial resolution is degraded by simple line doubling—artifacts such as flickering or "comb" effects in moving parts of the image which appear unless special signal processing eliminates them. A procedure known as deinterlacing can optimize the display of an interlaced video signal from an analog, DVD or satellite source on a progressive scan device such as an LCD television, digital video projector or plasma panel. Deinterlacing cannot, produce video quality, equivalent to true progressive scan source material. Aspect ratio describes the proportional relationship between the width and height of video screens and video picture elements.

All popular video formats are rectangular, so can be described by a ratio between width and height


Onna-bugeisha was a type of female warrior belonging to the Japanese nobility. These women engaged in battle alongside samurai men in times of need, they were members of the bushi class in feudal Japan and were trained in the use of weapons to protect their household and honour in times of war. Significant icons such as Tomoe Gozen, Nakano Takeko, Hōjō Masako are famous examples of onna-bugeisha. Long before the emergence of the renowned samurai class, Japanese fighters were trained to wield a sword and spear. Women learned to use naginata and the art of tantojutsu in battle; such training ensured protection in communities. One such woman known as Empress Jingū, used her skills to inspire economic and social change, she was recognized as the onna bugeisha who led an invasion of Korea in 200 AD after her husband Emperor Chūai, the fourteenth emperor of Japan, was slain in battle. According to the legend, she miraculously led a Japanese conquest of Korea without shedding a drop of blood. Despite controversies surrounding her existence and her accomplishments, she was an example of the onna bugeisha in its entirety.

Years after her death, Jingū was able to transcend the socioeconomic structures that were instilled in Japan. In 1881, Empress Jingū became the first woman to be featured on a Japanese banknote. Designed to stop counterfeiting, her image was printed on oblong paper; the Genpei War marked the war between the Minamoto clans. The epic The Tale of the Heike was composed in the early 13th century in order to commemorate the stories of courageous and devoted samurai. Among those was Tomoe Gozen, servant of Minamoto no Yoshinaka of the Minamoto clan, she assisted Yoshinaka in defending himself against the forces of his cousin, Minamoto no Yoritomo during the Battle of Awazu on February 21, 1184. In The Tale of the Heike, written at the beginning of 14th century, she was described:... beautiful, with white skin, long hair, charming features. She was a remarkably strong archer, as a swords-woman she was a warrior worth a thousand, ready to confront a demon or a god, mounted or on foot, she handled unbroken horses with superb skill.

Whenever a battle was imminent, Yoshinaka sent her out as his first captain, equipped with strong armor, an oversized sword, a mighty bow. Although she was not proven to be a historical figure, Tomoe Gozen has impacted much of the warrior class, including many traditional Naginata schools, her actions in battle received much attention in the arts plays such as Tomoe no Monogatari and various ukiyo-e. As time passed, the influence of onna-bugeisha saw its way from paintings to politics. Another famous female general of the Genpei War was Hangaku Gozen. While Tomoe Gozen was an ally of the Minamoto clan, Hangaku allied with the Taira clan; the existence of these two prominent female generals confirms that the status of women during this time was still less unequal than future periods. Several other women are supposed to have acted as samurai during this period, but many of them have been omitted from history. In ages past, it was more common to see women become reigning empresses, this would change in the future during the Meiji restoration.

Throughout Japanese history, while not becoming de jure chiefs of a samurai clan, several de facto ruled their clans. After the Heike were thwarted towards the western provinces of Japan, the Kamakura shogunate was soon established under the rule of Minamoto no Yoritomo. After he passed, his wife, Hōjō Masako, acting in the early years of the Hōjō regency, became the first onna-bugeisha to be a prominent player in politics. Masako became a Buddhist nun, a traditional fate of samurai widows, continued her involvement in politics, influencing the fates of her sons Minamoto no Yoriie and Minamoto no Sanetomo, the second and third shōgun, of the Hōjō faction at the shōguns' court. Through the collective efforts of Masako and a few political puppets, laws governing the shōgun's court in the early 13th century allowed women equal rights of inheritance with fraternal kin. Though the primary role of women in ancient Japan continued to be the support to their family and their husbands, they acquired a higher status in the household.

These laws allowed Japanese women to control finances, bequeath property, maintain their homes, manage servants, raise their children with proper, samurai upbringing. Japanese women were expected to defend their homes in times of war. During the Ashikaga Shogunate, due to tensions between the shogunate retainers, Japan goes to war again. In 1460, when shogun Ashikaga Yoshimasa abdicated his position to his younger brother Ashikaga Yoshimi, Hino Tomiko was against this decision. Tomiko sought political and military support to rule as regent until the birth of her son, she secured the support of Yamana Sōzen and other leaders of powerful samurai clans, she went to war against Yoshimasa and his supporters the Hosokawa clan. This dispute for succession led to the begin of the Sengoku period. In the Azuchi–Momoyama period several daimyos took charge of their own affairs and fought against each other by territory, women of noble clans and peasant women members of Ikkō-ikki, Ikkō-shu, Saika Ikki and others Ikki sects went to the battlefields.

In 1569, Ichikawa no Tsubone, the wife of a Mori family retainer from western Japan. When her husband was absent from the campaign, she as

Adrian Zandberg

Adrian Tadeusz Zandberg is a Polish historian and computer programmer, doctor of humanities and left-wing politician, member of the Board of the Razem party. His parents moved in 1967 from Poland to Denmark, where Zandberg was born in 1979. In 1985 his family moved back to Poland. After studying history at Warsaw University, he received his doctorate for his dissertation about British and German left-wing social democratic movements, he studied computer science at a Polish-Japanese computing academy. As a student he devoted himself to politics. On 14 November 2001, he published an article in the "Gazeta Wyborcza" daily newspaper written together with civil rights activist Jacek Kuroń on the topic of social justice in Poland, he was elected chairman of the youth wing of the Labour United party, was a member of the executive of this party and founded the Federation of Young Socialists. In May 2015, he became one of the founders of Partia Razem, a new political party, was elected to the nine-member Board, together with Jakub Baran, Aleksandra Cacha, Alicja Czubek, Maciej Konieczny, Magdalena Malińska, Mateusz Mirys, Katarzyna Paprota, Marcelina Zawisza.

Zandberg was placed on the first place on Razem's Warsaw candidate list of the Sejm elections in October 2015. As a Razem party representative during a television debate before the 2015 parliamentary elections, held in Poland on 25 October he represented the smallest of the eight parties. Among other positions, he was the only one of the eight panelists who pleaded for an unconditional acceptance of Syrian war refugees in Poland. Following the debate, some of the media declared him the winner of this discussion, his appearance at the debate generated more media interest in him and his party in the following days. Zandberg received 49,711 votes, but his party won only 3.62 percent of votes, so did not gain any seats in the Sejm. While some commentators claimed that the increase in popularity of Razem was at the expense of the United Left coalition, which did not win any seats, resulting in neither left-wing party being represented in the new parliament, including United Left leader Barbara Nowacka, disagreed with that assessment, pointing out that Razem attracted new electorate, few of its voters had voted for SLD or Twój Ruch in previous elections and that the decrease in popularity of United Left's member parties had been a steady process over the years due to past errors.

He has two children. As of 2015, he works professionally as a computer programmer. "Interview with Adrian Zandberg". OpenDemocracy. 2016-08-10. Retrieved 2016-08-17