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I need to load all the frames of an animated GIF to an HTML5 canvas.

Please note, I don't want to "play" the animated (someone asked this before), all I want is to extract all the frames to use them as single images.

Michał Perłakowski
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Omiod
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  • can u please be more specific –  Jan 10 '11 at 12:09
  • Sure. Using javascript+canvas, I wish to load a single "anim-gif" file (that is composed of many frames), and then I'd like to use each single extracted frame as single images. – Omiod Jan 10 '11 at 13:25

4 Answers4

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Buzzfeed have librarified the code from the repo tommitytom posted. I haven't tried it yet but it looks good.

https://github.com/buzzfeed/libgif-js

Brendan
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8

Take a look at jsgif; it downloads a GIF, parses it, and draws the individual frames of the file to a <canvas>. With a bit of digging you should be able to find the code that draws the individual frames and work from there.

tommitytom
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5

Sorry, the short answer is that JavaScript has no way of controlling the current frame of an Animated GIF.

The long answer is that there are sort-of ways to do what you want with just JS, but they are very much convoluted hacks.

Example of hackish way: Create a canvas and don't add it to the DOM (so this won't be seen by anyone). In a fast loop (setTimeout), draw to this canvas constantly and collect snapshots. Compare the canvas ImageData to see if the frames have changed or not.

It would be a better use of your time, probably, to see how you can get your server to split it apart for you (with php/perl/python/etc)

Simon Sarris
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    The hackish way is smart, but unpredictable. I agree that if no better JS solutions comes out, I'll have to resort to server side scripting... Thanks. – Omiod Jan 10 '11 at 17:06
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    This hack should not be possible. `when a CanvasImageSource object represents an animated image in an HTMLImageElement, the user agent must use the default image of the animation (the one that the format defines is to be used when animation is not supported or is disabled), or, if there is no such image, the first frame of the animation` https://html.spec.whatwg.org/multipage/scripting.html#dom-context-2d-drawimage#image-sources-for-2d-rendering-contexts – Robert Dec 22 '14 at 16:14
  • This response was probably correct at the time. But today using libgif-js can get the job done, and it pretty easy aswell. – Clive Paterson May 12 '16 at 03:51
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    it's not true, check this example: https://codepen.io/hoanghals/pen/dZrWLZ and `move_to()` function of the libgif-js – Flash Thunder Oct 29 '20 at 20:29
1

When you only need the first frame of the GIF:

const image = document.getElementById('my-image');
const canvas = document.getElementById('my-canvas');
const ctx = canvas.getContext("2d");
// context.drawImage(img, x, y, width, height);
ctx.drawImage(image, 0, 0);

Credits: How to draw a GIF on a canvas?

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