标题: [Unity 组件参考手册]组件：图像特效脚本之对比度增强 [打印本页] 作者: . 时间: 2013-1-31 21:18 标题: [Unity 组件参考手册]组件：图像特效脚本之对比度增强 The Contrast Enhance image effect enhances the impression of contrast for a given camera. It uses the well-known unsharp mask process available in image processing applications.对于一个特定的相机，对比度增强特效可以增强其生成图片的对比度感知。它主要使用了图像处理领域中著名的非锐化掩膜方法来达到这种效果。When blurring is applied to an image, the colors of adjacent pixels are averaged to some extent, resulting in a reduction of sharp edge detail. However, areas of flat color remain relatively unchanged. The idea behind unsharp masking is that an image is compared with a blurred (or "unsharp") version of itself. The difference in brightness between each pixel in the original and the corresponding pixel in the blurred image is an indication of how much constrast the pixel has against its neighbours. The brightness of that pixel is then changed in proportion to the local contrast. A pixel which is darker after blurring must be brighter than its neighbours, so its brightness is further increased while if the pixel is darker after blurring then it will be darkened even more. The effect of this is to increase contrast selectively in areas of the image where the detail is most noticeable. The parameters of unsharp masking are the pixel radius over which colors are blurred, the degree to which brightness will be altered by the effect and a "threshold" of contrast below which no change of brightness will be made.当向一张图片是用模糊化特效时，临近像素间的颜色将会被平均，这也就减少了锐利边缘的细节信息，但拥有平滑颜色过度的区域则相对地保持不变。非锐化掩膜的核心思想这是将一张图片与其自身的模糊化效果相比较，对于同一个像素来说，原始图像中的颜色与其在模糊化后图像的颜色差异，则表示该像素在其临域内具有多大的对比度。这样，就可以根据局部对比度来成比例地改变该像素的亮度。如果一个像素在模糊化后变得比原来暗，那说明该像素要比其临域内其他像素的颜色要亮，所以增强后其颜色会更亮，同理，如果该像素模糊后比原来亮，则增强后会变得更加暗。这种特效可以用来有选择地增加图像的对比度，特别是针对那些需要关注的细节。非锐化掩膜方法的参数有像素的模糊半径，增强系数以及对比度阈值，在此阈值之下的亮度将不受影响。As with the other image effects, this effect is only available in Unity Pro and you must have the Pro Standard Assets installed before it becomes available.跟其他图像特效一样，该特效只能用于Unity Pro版本中年，而且你在使用它之前需要安装Pro Standard Assets。
No Contrast Enhance 没有对比度增强特效
Contrast enhance enabled 使用对比度增强特效
[Properties 属性]-------------------------------------------------------------------------Intensity 强度
The intensity of contrast enhancement. 对比度增强的强度
Threshhold 阈值
The constrast threshold below which no enhancement is applied.
对于阈值以下的像素将不进行增强处理
Blur Spread 模糊扩散
The radius over which contrast comparisons are made.
在该半径下将进行对比度的比较 -------------------------------------------------------------------------[Hardware support 硬件支持]This effect requires a graphics card with pixel shaders (2.0) or OpenGL ES 2.0. PC: NVIDIA cards since 2003 (GeForce FX), AMD cards since 2004 (Radeon 9500), Intel cards since 2005 (GMA 900); Mobile: OpenGL ES 2.0; Consoles: Xbox 360, PS3.该特效要求在拥有像素着色器（3.0）或OpenGL ES2.0的显卡上进行。PC：2004年以后的NVIDIA卡（GeForce6），2005年以后的AMD卡（Radeon X1300），2006年以后的Intel卡（GMA X3000）；移动设备：OpenGL ES2.0；控制台：Xbox360，PS3。All image effects automatically disable themselves when they can not ***n on end-users graphics card.所有图像特效如果不能在用户终端的显卡上运行时则会自动关闭。
【来源：互联网】
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