Remember, any white pixels you put in your foreground image will provide a mask over the background frames.

记住，在您的前景图像中所使用的任何白色像素将提供背景帧的蒙版。

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When he finally made it to the medical office, the school nurse led him to a bed, removed his tie, then placed a mask over his mouth and nose. The cool rush of oxygen brought some relief.

他来到学校的医务室，护士让他躺在床上，松开他的领带，然后给他戴上氧气面罩 凉爽的氧气使他的症状得到一些缓解。

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Put the mask over your nose and mouth and breathe normally.

把面罩盖在口鼻上，像往常一样呼吸。

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The old man wore thick gloves on his hands and a mask over his mouth and nose.

VOA: special.2009.05.23

It seems that Lawes himself actually played the role of the attendant spirit, that beneficent, slightly frightening figure who hovers over the entire landscape of the mask.

看起来好像,劳斯自己扮演了跟班精神，那善行微妙地,让那些参与《面具》创作的人员产生了恐惧。

耶鲁公开课 - 弥尔顿课程节选

She was put on a non invasive ventilator, which included a mask over her face to help her to breathe.

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An ALA billboard ad in Michigan targeted House Energy and Commerce Committee Chairman Fred Upton, featuring a child with an oxygen mask over her face.

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If you want to watch Ben-Hur in the original aspect ratio of 2.76:1, Autoscope can handle it by moving a mask over the screen at an eightieth of an inch.

ENGADGET: Runco @ CEDIA - 1080p projectors HD