求图片根据四个坐标裁剪方法,该如何处理
求图片根据四个坐标裁剪方法
选定裁剪区域效果图
根据juqery图片插件 产生四个坐标参数
?x1=55&y1=17&x2=420&y2=265&file=images/1600x1200.jpg
根据这四个坐标参数,将原图1600*1200 在指定选择区域裁剪图片
请问下他这个坐标比例是怎么计算的? 比如x1坐标是55, 他并不是说x轴就从55开始..
另外是如何根据这四个坐标计算出要裁剪的图片大小为1269*1033
用这些GD库imagecopyresampled 处理函数 该怎么弄呢？求指教！3Q
------解决方案--------------------
你应该给出教程出处
------解决方案--------------------
需要知道1、2、3的参数
1、供裁剪时图片的高宽（拉伸/缩放的实际值）
2、裁剪框的起点坐标，及其裁剪框的长宽
3、你需要生成的图片的高宽
3、根据缩放的级别，计算出原图待裁剪的实际起点坐标，及裁剪区域在原图的实际长宽
4、用函数imagecopyresampled就得到你需要的图片了，参数自己看手册
------解决方案--------------------
确定了。起始坐标和宽高是不是长方形就确定了
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