无安全问题 我爸爸的出生地 我妈妈的出生地 我的小学校名 我的中学校名 我最喜欢的运动 我最喜欢的歌曲 我最喜欢的电影 我最喜欢的颜色 自定义问题
水墨江南
kohaku
春意盎然
紫色梦幻
绿之印象
蓝色天空
黑色旋风
引用 When the 16:9 aspect ratio was proposed by Kerns H. Powers, nobody was creating 16:9 videos. The popular choices in 1980 were 4:3 (based on television standard's ratio at the time), 1.66:1 (the European "flat" ratio), 1.85:1 (the American "flat" ratio), 2.20:1 (the ratio of 70 mm films) and 2.39:1 (the ratio of anamorphic widescreen films). Powers discovered that all of those aspects when normalised to constant area would fit within an outer rectangle and when over-lapped, all shared a common inner rectangle. The aspect ratio of these rectangles is simply the geometric mean of the extremes of 4:3 and 2.39:1, that is, 1.77:1, which is coincidentally close to 16:9, or 1.78:1.While 1.78:1 was initially selected as a compromise format, the popularity of HDTV broadcast has solidified 1.78:1 as perhaps the most important video aspect ratio for the future. Most 1.33:1 and 2.39:1 video is now recorded so that a 1.78:1 inner rectangle is "protected" for HD broadcast.
引用 最初由 physiophile 发布如此而已……lz要是再追问为啥开始是4:3,我也没辙了……
引用 最初由 逆鳞牙 发布日本那边流行16:9电视了吗,以前还真不知道。去年我家买的新电视都还是4:3的,看来中国和日本不一样。
引用 最初由 推倒机 发布去年那些高清宽屏壁挂电视都白菜价了吧
引用 最初由 joshown 发布:rolleyes:这ID是不是被盗用了啊