We will first talk about how to do resizing purely in JavaScript using the canvas element.There are libraries like fabric.js that offer rich APIs.Īpart from the above two reasons, in almost all cases, you would want to get the resized images from the backend itself so that client doesn't have to deal with heavy processing tasks. Image manipulation in JavaScript is done using the canvas element. Imagine this with operations like undo/redo and complex text and image overlays. If a user is manipulating a heavy image, it will take a lot of time to download transformed images from the server. The speed is critical for the user in these editors. Rich image editors that work on client-sideĪ rich image editor that offers image resize, crop, rotation, zoom IN and zoom OUT capabilities often require image manipulation on the client-side.You can first resize images on the browser and then upload them to reduce upload time and improve application performance. Uploading a large file on your server will take a lot of time. Resizing images before uploading to server.

However, there are a couple of situations where you might need to resize images purely using JavaScript on the client side. This approach also saves data while transmitting images from the server to the client. To guarantee that the aspect ratio options are respected by other modifiers, those modifiers must be in the aspectRatio.modifiers array option, not in the same resize.modifiers array as the aspectRatio one.Image resizing is computationally expensive and usually done on the server-side so that right-sized image files are delivered to the client-side.

Modifiers to apply to the resize which will be made to respect the aspect ratio options Increase edges by the same amount instead of maintaining the same ratio The aspect ratio to maintain or the value ‘preserve’ to maintain the starting ratio Interact.js comes with an aspectRatio modifier which can be used to force the resized rect to maintain a certain aspect ratio.

Resize js