Quality of Generated Image is Low

Question

I have this simple code

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 Dom to Image JavaScript Library for my simple project, but what i am facing is the generated image's quality is too low, like SVG is infinitely zoomable but PNG's quality is very low, i tried using {style: {transform: "scale(2)"}} this option in my domtoimage.toPng function but my Image is just overflowed to nothing.

Is there any way to change the height or width of the generated image so that it's quality is high

When i use transform style my generated image looks like this

Answer 1

Well thanks alot to some people i found out this working solution

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); });
}