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Showing posts from December 20, 2018

Opening Day

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For the Twilight Zone episode, see Opening Day (The Twilight Zone). Opening Day 2009 Opening Day at Dodger Stadium in Los Angeles Observed by United States, Canada 2019 date March 28 2020 date April 5 Frequency annual Opening Day is the day on which professional baseball leagues begin their regular season. For Major League Baseball and most of the minor leagues, this day typically falls during the first week of April. For baseball fans, Opening Day serves as a symbol of rebirth; writer Thomas Boswell once penned a book titled, Why Time Begins on Opening Day . [1] Many feel that the occasion represents a newness or a chance to forget last season, in that all 30 of the major league clubs and their millions of fans begin with 0–0 records. [1] Opening Day festivities extend throughout the sport of baseball, from hundreds of Minor League Baseball franchises to college, high school, and youth leagues in North America and beyond. Since Major League Baseball ge...

帧率

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幀率 是用於測量顯示帧数的量度。測量單位為「每秒顯示帧数」( Frame per Second ,FPS)或「赫茲」,一般來說FPS用於描述影片、電子繪圖或遊戲每秒播放多少幀。 目录 1 帧率与人眼 2 电影 2.1 无声电影 2.2 有声电影 3 数位视频和电视标准 3.1 畫面撕裂 4 常见影视帧率 5 參考資料 帧率与人眼 人类视觉的时间敏感性和分辨率根据视觉刺激的类型和特征而变化,并且在个体之间是不同的。由於人類眼睛的特殊生理結構,如果所看畫面之幀率高於每秒約10至12帧的時候,就會認為是連貫的 [1] ,此現象稱之為視覺暫留。這也就是為什麼電影膠片是一格一格拍攝出來,但是藉由快速播放,能讓畫面看起來是連續的。 当调制光(如计算机显示器)闪烁的频率高于約50Hz至60Hz时,主流研究把在此状态下的调制光认定为稳定状态。这种对调制光稳定感知,被称为闪烁融合阈值。然而,当调制光不均匀且包含图像时,所需要的闪烁融合阈值要高得多。 [2] 如果人需要在一连串不同图像中识别指定图像,图像出现时间仅需13毫秒。 [3] 视觉残留有时会导致非常短暂的单毫秒视觉刺激,其感知持续时间在100毫秒至400毫秒之间。多个短暂刺激有时也能合成单个刺激,例如在10毫秒的绿色闪光后出现10毫秒的红色闪光,会被感知为单一的黄色闪光。 [4] 电影 无声电影 早期的无声电影的帧率介于16到24帧/秒之间 [5] ,但是由于摄像机由手摇驱动,所以在摄影过程中经常改变帧率来表现情绪。要改变影院中的帧率,还可以通过调节放映机的卷片机构电压变阻器来完成。 [6] 无声电影常用比拍摄时更高的帧率来放映。 [7] 虽然帧率足以让人感觉到运动,但往往被认为是在放快镜。通过放映机上两片式或三片式的快门,将帧率提高到观众看到的两倍或三倍。托马斯·爱迪生曾指出,低于视觉皮层帧率下限48帧/秒,会导致眼睛疲劳。 [8] [9] 在1920年代中后期,无声电影的帧率提高到20至26帧/秒之间。 [8] 有声电影 当有声电影在1926年推出时,人耳对音频的变化更敏感,反而削弱人对电影帧率的关注。因为许多无声电影使用22至26帧/秒播放,所以选择中间值24帧/秒...

Nashville Sounds

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Minor League Baseball team Minor League Baseball team Nashville Sounds Founded in 1978 Nashville, Tennessee Team logo Cap insignia Class-level Current Triple-A (1985–present) Previous Double-A (1978–1984) Minor league affiliations League Pacific Coast League (1998–present) Conference American Conference Division Northern Division Previous leagues American Association (1985–1997) Southern League (1978–1984) Major league affiliations Current Texas Rangers (from 2019) Previous Oakland Athletics (2015–2018) Milwaukee Brewers (2005–2014) Pittsburgh Pirates (1998–2004) Chicago White Sox (1993–1997) Cincinnati Reds (1987–1992) Detroit Tigers (1985–1986) New York Yankees (1980–1984) Cincinnati Reds (1978–1979) Minor league titles League titles .mw-parser-output .nobold{font-weight:normal} (3) 1979 1982 2005 Conference titles (2) 2003 2005 Division titles (10) 1979 1981 1982 1990 199...