The method divides the background of fingerprint image into two layers: outboard black area and inboard tint area.

该方法将指纹图像的背景分为两层：外层黑色背景区域和内层浅色背景区域。

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Tint fine thread could be found in dark background after negative staining observed by TEM.

透射电镜下，经负染后，在深色的背景中间可见浅色细丝状。

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If your navigation bar uses them, you can also specify its tint color (with the TintColor key) or the name of its custom background image (with the BackgroundImage key).

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