Is there a way to use JCrop to crop an area larger than the actual image?

Question

From what I can tell, JCrop will not let me set things up so the user can crop outside the actual image and include surrounding whitespace. Is there a way to do that? To help explain what I mean, say we are restricting our crop to a 16:9 ratio. That works fine for an image with a naturally wide subject: But sometimes the source image that a user wants to use does not comfortably accommodate the desired ratio: Instead, we'd like to allow them to include space outside the image by making the crop area larger than the image itself: I've been messing around with JCrop and looking through the manual and Google for a while and it doesn't look like this is possible (without modifying JCrop). Am I wrong? If so, how do you do it? FWIW, the actual images in this case will be product/organization logo images, which come in a large variety of aspect ratios, and almost always the images available to people have almost no whitespace around the text/imagery. Which means any fixed aspect ratio crop r…

Accepted Answer

My solution was to create a temporary canvas with square dimensions equal to the largest side of the image. I made the canvas background white and added the image in the center. Then I created a new image and used the canvas as the image source. Then I used that image with jcrop. It's slower, but it works!

Here's an example:

```
img.onload = function(){ 
    // get the largest side of the image
    // and set the x and y coordinates for where the image will go in the canvas
    if( img.width > img.height ){
        var largestDim = img.width;
        var x = 0;
        var y = (img.width-img.height)/2;
    }
    else{
        var largestDim = img.height;
        var y = 0;
        var x = (img.height-img.width)/2;
    }
    // create a temporary canvas element and set its height and width to largestDim
    canvastemp = document.createElement("canvas");
    canvastemp.width = canvastemp.height = largestDim;
    var ctx = canvastemp.getContext('2d');
    // set the canvas background to white
    ctx.fillStyle="#FFFFFF";
    ctx.fillRect(0, 0, canvastemp.width, canvastemp.height);
    // center the image in the canvas
    ctx.drawImage(img, x, y, img.width, img.height);
    // create a new image and use the canvas as its source
    var squaredImg = document.createElement("img");
    squaredImg.src = canvastemp.toDataURL();
    // add jcrop once the image loads
    squaredImg.onload = function(){
        addJcrop(squaredImg);   
    }
};

function addJcrop(img){
   // your jcrop code
}
```

This way users can choose to include the entire image in the crop if they wish.

Is there a way to use JCrop to crop an area larger than the actual image?

Solution

Problem

Related problems