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I would like to use createElement("img') to create .jpeg extension instead of .png

According to Flanagan's book JavaScript: The Definitive Guide: Activate Your Web Pages By David Flanagan,

For jpeg image type, the second argument should be a number between 0 and 1 specifying the image quality level.

I am not sure what the syntax for the code would be.

Is it something like this?

createElement("img",1)

I would like to use createElement("img') to create .jpeg extension instead of .png

According to Flanagan's book JavaScript: The Definitive Guide: Activate Your Web Pages By David Flanagan,

For jpeg image type, the second argument should be a number between 0 and 1 specifying the image quality level.

I am not sure what the syntax for the code would be.

Is it something like this?

createElement("img",1)

• javascript
• jquery

Share Improve this question Follow asked Sep 26, 2011 at 20:56 Jason KimJason Kim 19.1k1313 gold badges6969 silver badges106106 bronze badges 2

• When you create an <img> element, it doesn't actually create an image. It creates an HTML element that can hold an image. You have to then specify the path to that image. What exactly are you trying to do? – John Kurlak Commented Sep 26, 2011 at 21:01
• You really have to buy the book to get that previous page, because there is no "type" attribute to createElement. Flanagan is referring to a different function. – John Kurlak Commented Sep 26, 2011 at 21:04

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3 Answers 3

Sorted by: Reset to default 4

The book is talking about html5's canvas tag and specifically its .toDataURL method.

I think you want to do something like:

var img = document.createElement('img');
img.src = 'myImageSource.jpg';

In this case, it's up to the web server to deliver the image and its type information to the web browser.

The book that you're referring to seems to be talking about the toDataURL method of the canvas API (see this), which accepts type and quality arguments.

You can use document.createElement without worrying about MIME types or quality.

you can use setAttrebure() Method or built-in 'src' property.

var img = document.createElement('img');
img.setAttibute('src', 'img.jpg');
document.body.appendChild(img);

or use

 var img = document.createElement('img');
 img.src = "img.jpg";
 document.body.appendChild(img);

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