为矩形图像创建重叠的方形面片

2024-09-30 18:19:14 发布

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给定为矩形图像img和面片s。现在,我想用边长为s的正方形面片覆盖整个图像,这样img中的每个像素至少在一个面片中,使用最少数量的面片。此外,我希望相邻的面片有尽可能少的重叠

到目前为止:我已经在下面包含了我的代码,并给出了一个示例。然而,它还不能完美地工作。希望有人能找到错误

示例:给定的是img的形状:(4616, 3016)s = 224 这意味着我将在较长的一侧添加21个补丁,在宽度较小的一侧添加14个补丁,总共添加21*14=294个补丁

现在,我试图找出补丁如何分布补丁之间的重叠。 我的补丁可以覆盖大小为:(4704, 3136)的图像,因此我的补丁在高度上必须覆盖88个重叠像素missing_h = ht * s - h,宽度类似

现在我想弄清楚,如何在21个补丁上分配88个像素。88 = 4* 21 + 4 因此,我将有hso = 17个重叠的面片shso = 4hbo = 4个重叠5的面片,宽度类似

现在我只需在整个图像上循环,并跟踪我当前的位置(cur_h, cur_w)。在每个循环之后,我调整,cur_h, cur_w。我有s,我当前的补丁编号i, j,它指示补丁是有小重叠还是有大重叠

import numpy as np

def part2(img, s):
    h = len(img)
    w = len(img[0])

    ht = int(np.ceil(h / s))
    wt = int(np.ceil(w / s))

    missing_h = ht * s - h
    missing_w = wt * s - w
    hbo = missing_h % ht
    wbo = missing_w % wt
    hso = ht - hbo
    wso = wt - wbo
    shso = int(missing_h / ht)
    swso = int(missing_w / wt)

    patches = list()
    cur_h = 0

    for i in range(ht):
        cur_w = 0
        for j in range(wt):
            patches.append(img[cur_h:cur_h + s, cur_w: cur_w + s])
            cur_w = cur_w + s
            if j < wbo:
                cur_w = cur_w - swso - 1
            else:
                cur_w = cur_w - swso
        cur_h = cur_h + s
        if i < hbo:
            cur_h = cur_h - shso - 1
        else:
            cur_h = cur_h - shso

    if cur_h != h or cur_w != w:
        print("expected (height, width)" + str((h, w)) + ", but got: " + str((cur_h, cur_w)))

    if wt*ht != len(patches):
        print("Expected number patches: " + str(wt*ht) + "but got: " + str(len(patches)) )


    for patch in patches:
        if patch.shape[0] != patch.shape[1] or patch.shape[0] != s:
            print("expected shape " + str((s, s)) + ", but got: " + str(patch.shape))
    return patches


def test1():
    img = np.arange(0, 34 * 7).reshape((34, 7))
    p = part2(img, 3)
    print("Test1 successful")


def test2():
    img = np.arange(0, 4616 * 3016).reshape((4616, 3016))
    p = part2(img, 224)
    print("Test2 successful")


test1()
test2()

Tags: 图像imgifnppatchhtprintshape