所以你可以选择模式简单，但是有较多明暗对比区域的图片。

So pick an image with simpler patterns, and lots of contrasting light and dark areas.

youdao

这些模式会由于图片的改动而改变。

These patterns change when the picture is manipulated.

youdao

下图里的每帧图片是在这种特定触发模式下拍摄的三分之一。

You’re actually seeing only about a third of the photos from this particular burst.

youdao

It turns out they're relatively simple to find even -- when they've been deleted whether accidentally - or in some cases intentionally-- that too is part of the job undeleting things that people had deleted.

原来，这些图片的模式很容易找到,即使他们已经被删除,无论是因为意外还是有人故意为之-,要恢复已删除的东西,需要做这部分的工作。

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