I noticed some knife marks on the pan.

我注意到锅上有些刀痕。

We can see the knife marks down the side which slip off at one point, so it's clearly been cut out of a bound volume.

我们可以看到边缘有刀的痕迹，因为刀划偏了，所以很明显这幅画是从一本合订本上割下来的。