The Laplacian method searches for zero crossings in the second derivative of the image to find edges.

拉普拉斯算子的方法是在图像的二阶导数搜索零交叉来查找边缘。

youdao

If I have a physically delimited portion of the image, I can easily find my way from there. I build from the edges to the core of the puzzle, ring by ring.

如果把这幅图的边角定好，就很容易继续了，从边角直到拼图的中心，一环扣一环。

youdao

If I have a physically delimited portion of the image, I can easily find my way from there.I build from the edges to the core of the puzzle, ring by ring.

如果把这幅图的边角定好，就很容易继续了，从边角直到拼图的中心，一环扣一环。

youdao

In short, you'll be hard-pressed to find any hard edges.

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He said Ubuntu makes it quicker and easier to find apps and content than other smartphones by swiping from the screen edges rather than going in and out with the home button to find and switch applications.

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Take a tour around the edges and you'll find two USB 2.0 ports (no USB 3.0), a Gigabit Ethernet jack and an HDMI socket.

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