java - 获取图像边界的程序

Question

给定像 here 这样的光栅图像，有没有一种方法可以使用 java 获取不同多边形的坐标，以便为 HTML 区域元素生成坐标？

下面给出了引用图像的示例 HTML 区域坐标:

<area shape="poly" alt="North West Delhi (SC)"
coords="224,148,237,122,243,117,249,120,262,116,286,119,311,132,314,120,320,
116,319,107,325,92,342,64,356,70,361,70,369,63,365,52,373,43,378,45,382,56,3
90,63,412,64,433,87,447,76,458,77,465,94,460,105,463,119,483,119,499,96,507,
93,507,81,526,82,547,79,570,88,574,95,571,104,583,129,584,138,577,147,576,16
5,552,158,548,184,567,202,549,209,532,202,531,194,523,194,519,189,496,190,48
4,187,469,199,461,198,457,201,458,212,436,219,436,225,444,224,444,231,459,23
5,473,239,477,237,483,244,496,240,512,245,513,254,499,264,495,271,502,275,49
4,289,496,292,493,299,487,292,480,296,473,284,456,294,447,307,438,328,422,34
4,401,352,397,361,393,424,379,424,349,454,342,440,339,419,327,415,321,392,29
8,401,267,400,254,420,249,430,246,427,241,407,207,403,192,401,192,384,206,35
5,178,333,196,301,193,292,189,288,191,279,172,263,179,248,189,241,177,224,18
3,200,172,190,166,189,172,175,175,162,178,155,194,162,199,153,198,143,205,13
9,211,139,221,149" nohref title="North West Delhi (SC)" />
<area shape="poly" alt="North East Delhi"
coords="642,288,631,280,633,271,638,261,636,255,633,252,623,254,602,241,602,
228,598,227,593,220,579,217,600,206,590,202,567,204,567,203,550,209,532,202,
531,195,522,193,520,189,496,190,484,187,469,199,461,198,458,200,458,210,455,
214,436,219,436,225,444,224,444,232,474,239,478,237,483,244,497,240,512,245,
513,253,498,265,496,272,502,274,494,289,495,294,504,291,524,294,540,302,554,
307,555,313,537,313,532,320,532,325,526,328,527,336,550,346,547,356,542,366,
545,372,555,365,561,373,564,379,554,389,557,396,565,398,569,384,572,384,579,
366,585,353,592,338,600,340,600,383,606,399,621,407,646,394,655,392,658,396,
694,391,701,386,718,380,745,360,734,348,737,338,736,333,746,322,728,324,725,
321,721,322,707,323,697,329,693,339,682,332,681,322,686,307,675,297,661,283,
655,288" nohref title="North East Delhi" />
<area shape="poly" alt="Chandni Chowk"
coords="492,394,426,386,423,405,429,412,423,413,409,413,393,424,397,359,402,
352,422,343,439,327,445,309,457,294,473,284,480,296,487,291,493,300,496,293,
507,292,524,294,544,303,554,308,555,313,536,313,532,320,532,325,526,329,527,
336,551,346,542,367,545,372,554,365,562,374,563,380,554,389,557,395,564,397,
566,398,570,383,573,384,592,339,600,341,600,383,606,400,619,406,632,420,627,
431,607,434,616,462,616,468,615,467,589,452,583,450,578,441,570,437,564,431,
561,429,556,420,557,413,549,413,544,408,527,402,526,412,521,414,513,412,516,
404,512,404,505,395,496,392" nohref title="Chandni Chowk" />

等等。请注意，我不想从 HTML 解析坐标我想从光栅图像生成坐标

Answer 1

正则表达式怎么样？

Pattern p = Pattern.compile("(?<=coords=\")(\\d+,)+\\d+(?=\")");
Matcher m = p.matcher(s);
while (m.find()) {
    String coord = m.group(1);
}

这假设上面给定的文本位于名为 s 的单行字符串中。