Quality of Generated Image is Low

我有这个简单的代码

function appendImg(imageData) {
    let img = new Image();
    img.src = imageData;
    document.getElementById("img-out-preview").innerHTML = '';
    document.getElementById("img-out-preview").appendChild(img);
    document.getElementById("img-preview-div").style.display = "block";
}

function saveAsPng() {
    var element = document.getElementById('output-location');

    domtoimage.toPng(element, {style: {transform: "scale(2)"}})
        .then(function (dataUrl) { appendImg(dataUrl) })
        .catch(function (error) { console.error('oops, something went wrong!', error); });
}

function saveAsSvg() {
    const filter = (node) => { return (node.tagName !== 'i'); }

    domtoimage.toSvg(document.getElementById('output-location'), {filter: filter})
        .then(function (dataUrl) { appendImg(dataUrl) })
        .catch(function (error) { console.error('oops, something went wrong!', error); });
}

$("#save-svg").on("click", saveAsSvg);
$("#save-png").on("click", saveAsPng);

/*! dom-to-image 10-06-2017 */
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@import url('https://fonts.googleapis.com/css2?family=Poppins:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;1,400;1,500;1,600;1,700;1,800&display=swap');

* { box-sizing: border-box; margin: 0; transition: all .3s ease; }
body { color: #333; background-color: #fefefe; font-family: 'Poppins', sans-serif; }
.wrapper { width: 90%; margin: 0 auto; text-align: center; }
button { color: #fff; background-color: #1a6ce9; padding: 10px; border-radius: 5px; outline: none; border: none; cursor: pointer; font-size: 1.3em; }
button:hover { background-color: #1158c4; }
input#text-input { width: 50%; padding: .5em; outline: none; min-width: 250px; border-radius: 5px; border: 3px solid #333; font-size: calc(80% + 1vw); }
input#text-input:focus { border-color: #1a6ce7a6; }
#html-output { margin: 30px auto; }
.heading { margin: 20px auto; }
#output-location { border-radius: 3px; padding: 10px; }
#img-preview-div { display: none; margin-top: 2vh; border: 1px dashed; }
kbd { display: inline-block; margin: .2em .3em; padding: .1em .6em; font: 400 calc(60% + 1vw)/1.4 'Poppins', sans-serif; background-color: #353535; color: #fff; border: 5px solid #555; border-top: 2px solid #555; border-radius: 3px; }
#output-location:not(kbd) { font-size: calc(70% + 1vw); font-weight: 600; }
h1 { font-size: calc(150% + 1vw); }
p { font-size: calc(40% + 1vw); }
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>


<div class="wrapper">
    <div class="heading">
        <h1>Key2Img</h1>
        <p>A Keyboard Shortcut To Image Generator</p>
    </div>

    <input type="text" id="text-input" placeholder="Example: Ctrl + Alt + C"/>

    <div id="html-output">
        <p>HTML Output</p>
        <p id="output-location">
            <kbd>Ctrl</kbd>+<kbd>Alt</kbd>+<kbd>C</kbd>
        </p>
    </div>

    <div class="btnHolder">
        <button class="btn btn-primary" type="button" id="save-svg">SVG</button>
        <button class="btn btn-primary" type="button" id="save-png">PNG</button>
    </div>

    <div id="img-preview-div">
        <p>Generated Image</p>
        <div id="img-out-preview"></div>
    </div>
</div>

I used 编辑到图像javascript库为我的简单项目,但是我面临的是生成的图像的质量太低,就像svg是无限的灰化,但PNG的质量非常低,我尝试过{style: {transform: "scale(2)"}}此选项在我的domtoimage.toPng功能,但我的图像只是溢出到任何东西。

有任何方法可以改变生成图像的高度或宽度,以便它的质量很高

我使用时transform我所生成的图像看起来像这样

This

"like SVG is infinitely zoomable but PNG's quality is very low"-为什么你期望一系列像素(PNG)表现得像矢量图(SVG)?Andreas
The issue tracker for the library has 与质量有关的一些问题结果图像。他们都有可能的修复。Andreas
@ andreas感谢我找到了解决方案Admi

回答 1

  1. 赞同 0

    谢谢很多我发现这个工作解决方案的人

    function saveAsPng() {
        let element = document.getElementById('html-output')
        let scale = 2;
    
        domtoimage.toPng(element, {
                width: element.clientWidth * scale,
                height: element.clientHeight * scale,
                style: { transform: 'scale('+scale+')', transformOrigin: 'top left'}
            })
            .then(function (dataUrl) { appendImg(dataUrl) })
            .catch(function (error) { console.error('oops, something went wrong!', error); });
    }
    

    Admi