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

I want to convert SVG into bitmap images (like JPEG, PNG, etc.) through JavaScript.

What task is it that you actually want to accomplish? Even though echo-flows answer tell us that it is (in some browsers) possible there are better and easier conversion methods for almost all practical cases.
Here's an example using d3: stackoverflow.com/a/23667012/439699
svgopen.org/2010/papers/62-From_SVG_to_Canvas_and_Back - Works perfectly! [On the link page, sourceSVG = $("#your_svg_elem_name").get(0) ]

C
Community

Here is how you can do it through JavaScript:

Use the canvg JavaScript library to render the SVG image using Canvas: https://github.com/gabelerner/canvg 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?


This isn't strictly Javascript, but HTML5 as well. This will not work on IE8, or any other browser that does not support HTML5 Canvas.
If the browser supports SVG and canvas, then there would be a much simpler way to load the SVG into memory and then paint it into a canvas, without the need for Canvg, which is a pretty large library because it handles all the SVG parsing that an SVG-supporting browser already provides for free. I'm not sure if this satisfies the original use-case, but if so, then see this resource for details.
Thanks for not supporting IE8. People should understand that it's time to move on.
You can now use the JavaScript SVG library Pablo to achieve this (I made it). See the toImage() and also download() for an auto-downloaded image.
svgopen.org/2010/papers/62-From_SVG_to_Canvas_and_Back - Works perfectly! [On the link page, sourceSVG = $("#your_svg_elem_name").get(0) ]
P
Pranav 웃

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...
});

canvg need the second parameter to be <svg>...</svg but jquery html() function don't add svg tag, so this code works for me but I needed to edit the canvg live to canvg('canvas', '<svg>'+$("#editor").html()+'</svg>');
@Luckyn if you call $(selector).html() on the parent of your svg element, it will work
@Luckyn and @jonathanGB, you shouldn't have to use html() on wrappers, or manually construct the parent svg tag -- which might even have attributes you leave out with this hack. Just use $(svg_elem)[0].outerHTML gives you the full source of the svg and its contents. Just saying...
w
worstenbrood

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;
}

This is not working in IE11, because of the security issue with .msToBlob()
Thanks!! I love how this works for both a "local" SVG HTML node and a remote SVG URL. Plus it doesn't require a full external library
Could you provide a usage example?
This copyStylesInline helped me a lot!! Without adding that, my exported png was looking very weird. Thank you!
S
Sundeep Pidugu

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

const svg=` 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 solution does not work for complex SVG (e.g. patterns with images)
Here is your code but optimized, but thank you for that... codepen.io/arcaelas-the-looper/pen/wvrqzvm
Thanks you @AlejandroReyes
You are welcome, u can followme in github: arcaelas
C
Cels

My use case was to have the svg data loaded from a network and this ES6 Class did the Job.

class SvgToPngConverter {
  constructor() {
    this._init = this._init.bind(this);
    this._cleanUp = this._cleanUp.bind(this);
    this.convertFromInput = this.convertFromInput.bind(this);
  }

  _init() {
    this.canvas = document.createElement("canvas");
    this.imgPreview = document.createElement("img");
    this.imgPreview.style = "position: absolute; top: -9999px";

    document.body.appendChild(this.imgPreview);
    this.canvasCtx = this.canvas.getContext("2d");
  }

  _cleanUp() {
    document.body.removeChild(this.imgPreview);
  }

  convertFromInput(input, callback) {
    this._init();
    let _this = this;
    this.imgPreview.onload = function() {
      const img = new Image();
      _this.canvas.width = _this.imgPreview.clientWidth;
      _this.canvas.height = _this.imgPreview.clientHeight;
      img.crossOrigin = "anonymous";
      img.src = _this.imgPreview.src;
      img.onload = function() {
        _this.canvasCtx.drawImage(img, 0, 0);
        let imgData = _this.canvas.toDataURL("image/png");
        if(typeof callback == "function"){
            callback(imgData)
        }
        _this._cleanUp();
      };
    };

    this.imgPreview.src = input;
  }
}

Here is how you use it

let input = "https://restcountries.eu/data/afg.svg"
new SvgToPngConverter().convertFromInput(input, function(imgData){
    // You now have your png data in base64 (imgData). 
    // Do what ever you wish with it here.
});

If you want a vanilla JavaScript version, you could head over to Babel website and transpile the code there.


M
Mahdi Khalili

change svg to match your element

function svg2img(){
    var svg = document.querySelector('svg');
    var xml = new XMLSerializer().serializeToString(svg);
    var svg64 = btoa(xml); //for utf8: btoa(unescape(encodeURIComponent(xml)))
    var b64start = 'data:image/svg+xml;base64,';
    var image64 = b64start + svg64;
    return image64;
};svg2img()

it's not working for me, i get this error: Uncaught TypeError: Failed to execute 'serializeToString' on 'XMLSerializer': parameter 1 is not of type 'Node'.
@Xsmael try to Switch the DOMParser interface developer.mozilla.org/en-US/docs/Web/API/DOMParser
Thanks, this works for me. No need to use external library.
@RyanArqueza what how?
@MTZ you should consider using utf8 part for utf8 characters for example your SVG contains non ASCI characters
k
klues

Here a function that works without libraries and returns a Promise:

/**
 * converts a base64 encoded data url SVG image to a PNG image
 * @param originalBase64 data url of svg image
 * @param width target width in pixel of PNG image
 * @return {Promise<String>} resolves to png data url of the image
 */
function base64SvgToBase64Png (originalBase64, width) {
    return new Promise(resolve => {
        let img = document.createElement('img');
        img.onload = function () {
            document.body.appendChild(img);
            let canvas = document.createElement("canvas");
            let ratio = (img.clientWidth / img.clientHeight) || 1;
            document.body.removeChild(img);
            canvas.width = width;
            canvas.height = width / ratio;
            let ctx = canvas.getContext("2d");
            ctx.drawImage(img, 0, 0, canvas.width, canvas.height);
            try {
                let data = canvas.toDataURL('image/png');
                resolve(data);
            } catch (e) {
                resolve(null);
            }
        };
        img.onerror = function() {
            resolve(null);
        };
        img.src = originalBase64;
    });
}

On Firefox there is an issue for SVGs without set width / height.

See this working example including a fix for the Firefox issue.


Didn't work for me in Safari, just hung, no error
Thanks for testing, I didn't test with Safari before. So there is also no error in the Javascript console, which would be strange?
Yes, very odd in my experience, but I didn't have more time to waste on it unfortunately
Thanks for including that fantastic example!
1) I suggest attaching to img.onerror also to not risk stalling the Promise in that case. 2) you don't have to attach the image to the document.body.
a
albert

Svg to png can be converted depending on conditions:

If svg is in format SVG (string) paths:

create canvas

create new Path2D() and set svg as parameter

draw path on canvas

create image and use canvas.toDataURL() as src.

example:

const canvas = document.createElement('canvas');
const ctx = canvas.getContext('2d');
let svgText = 'M10 10 h 80 v 80 h -80 Z';
let p = new Path2D('M10 10 h 80 v 80 h -80 Z');
ctx.stroke(p);
let url = canvas.toDataURL();
const img = new Image();
img.src = url;

Note that Path2D not supported in ie and partially supported in edge. Polyfill solves that: https://github.com/nilzona/path2d-polyfill

Create svg blob and draw on canvas using .drawImage():

make canvas element

make a svgBlob object from the svg xml

make a url object from domUrl.createObjectURL(svgBlob);

create an Image object and assign url to image src

draw image into canvas

get png data string from canvas: canvas.toDataURL();

Nice description: https://web.archive.org/web/20200125162931/http://ramblings.mcpher.com:80/Home/excelquirks/gassnips/svgtopng

Note that in ie you will get exception on stage of canvas.toDataURL(); It is because IE has too high security restriction and treats canvas as readonly after drawing image there. All other browsers restrict only if image is cross origin.

Use canvg JavaScript library. It is separate library but has useful functions.

Like:

ctx.drawSvg(rawSvg);
var dataURL = canvas.toDataURL();

3rd link is broken
yes, indeed. I don't know how to reach there now. But description above can be enough for some understanding. Good idea for future co copy some context after the reference
fixed linkrot. the wayback machine is your friend for fixing linkrot.
c
cancerbero

I recently discovered a couple of image tracing libraries for JavaScript that indeed are able to build an acceptable approximation to the bitmap, both size and quality. I'm developing this JavaScript library and CLI :

https://www.npmjs.com/package/svg-png-converter

Which provides unified API for all of them, supporting browser and node, non depending on DOM, and a Command line tool.

For converting logos/cartoon/like images it does excellent job. For photos / realism some tweaking is needed since the output size can grow a lot.

It has a playground although right now I'm working on a better one, easier to use, since more features has been added:

https://cancerberosgx.github.io/demos/svg-png-converter/playground/#


f
foske

There are several ways to convert SVG to PNG using the Canvg library.

In my case, I needed to get the PNG blob from inline SVG.

The library documentation provides an example (see OffscreenCanvas example).

But this method does not work at the moment in Firefox. Yes, you can enable the gfx.offscreencanvas.enabled option in the settings. But will every user on the site do this? :)

However, there is another way that will work in Firefox too.

const el = document.getElementById("some-svg"); //this is our inline SVG

var canvas = document.createElement('canvas'); //create a canvas for the SVG render
canvas.width = el.clientWidth; //set canvas sizes
canvas.height = el.clientHeight;

const svg = new XMLSerializer().serializeToString(el); //convert SVG to string

//render SVG inside canvas
const ctx = canvas.getContext('2d');
const v = await Canvg.fromString(ctx, svg);
await v.render();

let canvasBlob = await new Promise(resolve => canvas.toBlob(resolve));

For the last line thanks to this answer


U
Umair Khan

Here are my 2 cents. Somehow Download anchor tag is not working as expected in code snippet, however it was working fine in Chrome.

Here is working jsFiddle

const waitForImage = imgElem => new Promise(resolve => imgElem.complete ? resolve() : imgElem.onload = imgElem.onerror = resolve); const svgToImgDownload = ext => { if (!['png', 'jpg', 'webp'].includes(ext)) return; const _svg = document.querySelector("#svg_container").querySelector('svg'); const xmlSerializer = new XMLSerializer(); let _svgStr = xmlSerializer.serializeToString(_svg); const img = document.createElement('img'); img.src = 'data:image/svg+xml;base64,' + window.btoa(_svgStr); waitForImage(img) .then(_ => { const canvas = document.createElement('canvas'); canvas.width = _svg.clientWidth; canvas.height = _svg.clientHeight; canvas.getContext('2d').drawImage(img, 0, 0, _svg.clientWidth, _svg.clientHeight); return canvas.toDataURL('image/' + (ext == 'jpg' ? 'jpeg' : ext), 1.0); }) .then(dataURL => { console.log(dataURL); document.querySelector("#img_download_btn").innerHTML = `Download`; }) .catch(console.error); }; document.querySelector('#map2Png').addEventListener('click', _ => svgToImgDownload('png')); document.querySelector('#map2Jpg').addEventListener('click', _ => svgToImgDownload('jpg')); document.querySelector('#map2Webp').addEventListener('click', _ => svgToImgDownload('webp'));