r - 已知植物位置的裁剪行检测 - 如何？

Question

通过图像识别和分割，我已经获得了田野上植物的抽象表示(即我确切地知道图像中所有植物的所有坐标)。

现在我想检测这个抽象表示中的裁剪行 - 但不太清楚如何做。我的问题是:

1. 图像中的行可能有点旋转，而不是完全在北/南方向(角度可能在 -10° 到 +10° 之间变化)
2. 每张图片的裁剪行数可能因图片而异且不固定 - 在处理之前也是未知的
3. 在每张处理过的图像中，裁剪行的旋转可能略有不同
4. 我有数百个图像/表示要处理(所以手工处理显然不太可行 :-))，所以我需要一个以后可以使用的算法，例如放入循环

您能否至少帮助我制定一种策略(或代码片段)来进行此类裁剪行检测？理想情况下，对于每个裁剪行，我最终都会有一个线性方程 (y=m*x+t) 的参数，以便可以使用 abline()，但我对任何事情都持开放态度。最后它可能看起来像这样(这里纯粹是为了手工完成的说明目的):

图像的基础数据在这里:

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Answer 1

下面是一些可能有帮助的东西:

对于每个检测到的植物点，找到最近的相邻植物。希望这能更频繁地在同一裁剪行中找到植物。如果先验地知道图像大致在北/南方向，我们应该更喜欢在垂直方向上看更多来选择邻近的植物。一种方法是将最近邻搜索的“距离”重新定义为各向异性的东西，例如

distance = 10 * (x0 - x1)² + (y0 - y1)²

下面是它产生的图，在每株植物和它最近的邻居之间画了一条线段:

它并不完美，但可能是一个有用的开始。大多数裁剪行都很幸运，4 株或更多株植物被正确地链接在一起。

从这里开始思考可能的策略:

1. 识别连接的组件，即植物的“链条”。

2. 对于每条链，通过最小二乘法回归最佳拟合线。或者更好的是，使用 RANSAC algorithm这样拟合就可以稳健地忽略共线链中的单个杂散植物。

3. 再次使用粗略的北/南方向，只有当它足够接近垂直时才认为最佳拟合线“有效”。假设它是有效的，找到所有接近最佳拟合线的植物。如果附近有许多植物，那么最适合的线可能是裁剪行。