The second algorithm is proposed because the method of difference image is not effective when the different information coming from two frames of difference image is too much or too little.

算法二是针对两帧差分图像之间所提供的差异信息过多或过少这两种极端情况，用差影法粗分割对人脸图像进行预处理时失效而提出来的。

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First based on the difference image and the skin color the face is detected and localized, then features are extracted by using improved SVD, last the features is classified by minimal distance.

首先基于差分图像和肤色信息检测出人脸，其次使用改进的奇异值分解方法提取面部特征，最后运用最小距离分类器进行识别。

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In this paper, a fast human face detection method based on difference image and multi-templates matching is proposed.

提出了一种用差影法与多模板匹配快速实现人脸检测的方法。

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The difference is between actively sharing information -- uploading an image with location data, checking into a restaurant or other business -- and passively sharing it (what the tech companies like to call "frictionless" sharing).

CNN: Facebook Home, privacy and you

When viewing from six meters away, the difference between native and upscaled was there but it was subtle -- it was just a sense of the image being sharper and more natural at the edges of objects.

ENGADGET: This is what native 4K home cinema looks like on Sony's VPL-VW1000ES projector

The new Kinect -- which we've heard of in the past -- is said to capture up to six people at once, and an alleged image demonstrating the difference between new and old versions of the camera puts much higher specs on said device (1920x1080 color resolution, more trackable joints, improved depth resolution, etc.).

ENGADGET