Convert SVG to image (JPEG, PNG, etc.) in the browser

The solution to convert SVG to blob URL and blob URL to png image

const svg=`<svg version="1.1" baseProfile="full" width="300" height="200"
xmlns="http://www.w3.org/2000/svg">
   <rect width="100%" height="100%" fill="red" />
   <circle cx="150" cy="100" r="80" fill="green" />
   <text x="150" y="125" font-size="60" text-anchor="middle" fill="white">SVG</text></svg>`
svgToPng(svg,(imgData)=>{
    const pngImage = document.createElement('img');
    document.body.appendChild(pngImage);
    pngImage.src=imgData;
});
 function svgToPng(svg, callback) {
    const url = getSvgUrl(svg);
    svgUrlToPng(url, (imgData) => {
        callback(imgData);
        URL.revokeObjectURL(url);
    });
}
function getSvgUrl(svg) {
    return  URL.createObjectURL(new Blob([svg], { type: 'image/svg+xml' }));
}
function svgUrlToPng(svgUrl, callback) {
    const svgImage = document.createElement('img');
    // imgPreview.style.position = 'absolute';
    // imgPreview.style.top = '-9999px';
    document.body.appendChild(svgImage);
    svgImage.onload = function () {
        const canvas = document.createElement('canvas');
        canvas.width = svgImage.clientWidth;
        canvas.height = svgImage.clientHeight;
        const canvasCtx = canvas.getContext('2d');
        canvasCtx.drawImage(svgImage, 0, 0);
        const imgData = canvas.toDataURL('image/png');
        callback(imgData);
        // document.body.removeChild(imgPreview);
    };
    svgImage.src = svgUrl;
 }

This seems to work in most browsers:

function copyStylesInline(destinationNode, sourceNode) {
   var containerElements = ["svg","g"];
   for (var cd = 0; cd < destinationNode.childNodes.length; cd++) {
       var child = destinationNode.childNodes[cd];
       if (containerElements.indexOf(child.tagName) != -1) {
            copyStylesInline(child, sourceNode.childNodes[cd]);
            continue;
       }
       var style = sourceNode.childNodes[cd].currentStyle || window.getComputedStyle(sourceNode.childNodes[cd]);
       if (style == "undefined" || style == null) continue;
       for (var st = 0; st < style.length; st++){
            child.style.setProperty(style[st], style.getPropertyValue(style[st]));
       }
   }
}

function triggerDownload (imgURI, fileName) {
  var evt = new MouseEvent("click", {
    view: window,
    bubbles: false,
    cancelable: true
  });
  var a = document.createElement("a");
  a.setAttribute("download", fileName);
  a.setAttribute("href", imgURI);
  a.setAttribute("target", '_blank');
  a.dispatchEvent(evt);
}

function downloadSvg(svg, fileName) {
  var copy = svg.cloneNode(true);
  copyStylesInline(copy, svg);
  var canvas = document.createElement("canvas");
  var bbox = svg.getBBox();
  canvas.width = bbox.width;
  canvas.height = bbox.height;
  var ctx = canvas.getContext("2d");
  ctx.clearRect(0, 0, bbox.width, bbox.height);
  var data = (new XMLSerializer()).serializeToString(copy);
  var DOMURL = window.URL || window.webkitURL || window;
  var img = new Image();
  var svgBlob = new Blob([data], {type: "image/svg+xml;charset=utf-8"});
  var url = DOMURL.createObjectURL(svgBlob);
  img.onload = function () {
    ctx.drawImage(img, 0, 0);
    DOMURL.revokeObjectURL(url);
    if (typeof navigator !== "undefined" && navigator.msSaveOrOpenBlob)
    {
        var blob = canvas.msToBlob();         
        navigator.msSaveOrOpenBlob(blob, fileName);
    } 
    else {
        var imgURI = canvas
            .toDataURL("image/png")
            .replace("image/png", "image/octet-stream");
        triggerDownload(imgURI, fileName);
    }
    document.removeChild(canvas);
  };
  img.src = url;
}

Here is how you can do it through JavaScript:

1. Use the canvg JavaScript library to render the SVG image using Canvas: https://github.com/gabelerner/canvg
2. Capture a data URI encoded as a JPG (or PNG) from the Canvas, according to these instructions: Capture HTML Canvas as gif/jpg/png/pdf?

jbeard4 solution worked beautifully.

I'm using Raphael SketchPad to create an SVG. Link to the files in step 1.

For a Save button (id of svg is "editor", id of canvas is "canvas"):

$("#editor_save").click(function() {

// the canvg call that takes the svg xml and converts it to a canvas
canvg('canvas', $("#editor").html());

// the canvas calls to output a png
var canvas = document.getElementById("canvas");
var img = canvas.toDataURL("image/png");
// do what you want with the base64, write to screen, post to server, etc...
});