I want to show an image from an URL with a certain width and height even if it has a different size ratio. So I want to resize (maintaining the ratio) and then cut the image to the size I want. I can resize with html img property and I can cut with background-image. How can I do both? Example: This image: Has the size 800x600 pixels and I want to show like an image of 200x100 pixels With img I can resize the image 200x150px: <img style="width: 200px; height: 150px;" src="http://i.stack.imgur.com/wPh0S.jpg"> That gives me this: <img style="width: 200px; height: 150px;" src="https://i.stack.imgur.com/wPh0S.jpg"> And with background-image I can cut the image 200x100 pixels. <div style="background-image: url('https://i.stack.imgur.com/wPh0S.jpg'); width:200px; height:100px; background-position:center;"> </div> Gives me: <div style="background-image:url('https://i.stack.imgur.com/wPh0S.jpg'); width:200px; height:100px; background-position:center;"> </div> How can I do both? Resize the image and then cut it the size I want?
当前回答
你可以使用Kodem的图片调整服务。您可以通过http调用调整任何图像的大小。可以在浏览器中随意使用，也可以在生产应用程序中使用。
上传图片到你喜欢的地方(S3, imgur等) 将其插入到您的专用API url(从我们的仪表板)
其他回答
使用CSS3，可以通过background-size来改变背景图像的大小，同时实现这两个目标。
在css3.info上有很多例子。
基于您的示例实现，使用donald_duck_4.jpg。在本例中，background-size: cover;正是你想要的-它适合背景图像覆盖整个区域的包含<div>和剪辑多余的部分(取决于比例)。
.with-bg-size { 背景图片:url (https://i.stack.imgur.com/wPh0S.jpg); 宽度:200 px; 身高:100 px; 背景位置:中心; /*使背景图像覆盖<div>的区域，并剪辑多余的*/ background-size:封面; ｝ <div class="with-bg-size">唐老鸭!< / div >
Css3 background-image background-size
我所做的是创建一个服务器端脚本，它将在服务器端调整大小和裁剪图片，这样它就会在互联网上发送更少的数据。
它相当简单，但如果有人感兴趣，我可以挖掘并发布代码(asp.net)
你也可以使用一个叫做Croppie的工具来裁剪图片…
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
<link href="https://foliotek.github.io/Croppie/croppie.css" rel="stylesheet" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"> </script>
<script src="https://foliotek.github.io/Croppie/croppie.js"> </script>
<script src="https://foliotek.github.io/Croppie/bower_components/exif-js/exif.js"> </script>
<style>
#page {
background: #ffffff;
padding: 20px;
margin: 20px;
}
#demo-basic {
width: 600px;
height: 600px;
}
</style>
</head>
<body>
<h1>Crop Image Demo</h1>
<input id="upload" type="file" />
<br />
<div id="page">
<div id="demo-basic"></div>
</div>
<input id="upload-result" type="button" value="Crop Image"/>
<br />
<img id="cropped-result" src=""/>
<script>
var $uploadCrop;
$("#upload").on("change", function () { readFile(this); show(); });
$("#upload-result").on("click", function (ev) {
$uploadCrop.croppie("result", {
type: "canvas",
size: "viewport"
}).then(function (resp) {
$("#cropped-result").attr("src", resp);
});
});
function show() {
$uploadCrop = $("#demo-basic").croppie({
viewport: { width: 100, height: 100 },
boundary: { width: 300, height: 300 },
enableResize: true,
enableOrientation: true,
mouseWheelZoom: 'ctrl',
enableExif: true
});
}
function readFile(input) {
if (input.files && input.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
$("#demo-basic").addClass("ready");
$uploadCrop.croppie("bind", {
url: e.target.result
}).then(function () {
console.log("jQuery bind complete");
});
}
reader.readAsDataURL(input.files[0]);
}
else {
alert("Sorry - you're browser doesn't support the FileReader API");
}
}
</script>
</body>
</html>
您可以将img标记放在div标记中，但我建议不要在浏览器中缩放图像。它在大多数时候都做得很糟糕，因为浏览器的缩放算法非常简单。最好先在Photoshop或ImageMagick中进行缩放，然后将其漂亮地提供给客户端。
在裁剪类中，放置你想要显示的图像大小:
.crop {
width: 282px;
height: 282px;
overflow: hidden;
}
.crop span.img {
background-position: center;
background-size: cover;
height: 282px;
display: block;
}
html看起来像这样:
<div class="crop">
<span class="img" style="background-image:url('http://url.to.image/image.jpg');"></span>
</div>
