Cloudinary Blog

Automatic image sharpening and blurring in the cloud

Images. Your web (or mobile) application is probably filled to the brim with images. You might be surprised at just how much impact these images have on your visitors. From their graphical appeal to their size and access times - these images determine your visitors browsing experience and ultimately their conversion to repeating visitors and paying clients.
 
Now, while your graphic designer has created a cool graphical concept, many of the images you need to embed inside it are not in your direct control. Social websites contain profile photos uploaded by their users. E-commerce solutions contain many product photos that can't be edited one at a time. Media outlets contain many photographs of different consistency.
 
Having a tool in your belt that offers automatic tweaks and retouches for all these images is quite handy. Here a couple of things you can do with Cloudinary that can really improve your website.

Image sharpening

How can you make your website "pop"? it's easy if you control the exact content across your web application - a great graphics design can make wonders. But what can we do to improve user uploaded images? 
 
Let's look look at the following image uploaded to Cloudinary:
  
 
The photo looks good. But just take a look at what a bit of sharpness can do to it. 
You can add sharpness by setting the effect transformation parameter to sharpen (or e_sharpen for URLs):
 
 
 
Here's the same example in Rails:
<%= cl_image_tag("front_face.jpg", :effect => "sharpen") %>
You can control the strength of the sharpen effect to match your taste. Here's a more intense sharpening of the same image by setting the sharpen level to 300. Quite a nice photographic effect.
 
 

 
Same example in PHP:
<?php echo cl_image_tag("front_face.jpg", array("effect" => "sharpen:300")) ?>
Sharpening is also useful in making text elements in thumbnails clearer. For example, the following screenshot was uploaded to Cloudinary. As you can see the small gray text snippets are not so clear here.
 
 
 
 
Sharpening such an screenshot would make the text more readable. The following example sharpened this image. This time using the unsharp_mask effect that is similar to sharpen but uses a different algorithm. Much more readable:
 
 
 
 
Same example in Django:
img = cloudinary.CloudinaryImage("front_face.jpg")
img.image(effect="unsharp_mask")

Image blurring

Image sharpening is useful for improving images and making them "pop". But sometimes you would want to aim for the opposite effect. Quora, for example, is using dynamically created blurred snippets of text if you're browsing an answer while being logged out. How can you do that using Cloudinary?
 
To blur images, you can use Cloudinary's blur effect (e_blur for URLs). Here's an example: 
 
 
 
 
You can also make the blurring more intense by passing a numeric level. The following example applies the blur effect with a 400 intensity on the sample image:
 
 
 
In the following example, we blurred the image intensely and also reduced its opacity. Then we added a text overlay that calls users to sign up to your site if they want to view the full content:
 
 
 
Sample example in Rails:
<%= cl_image_tag("front_face.jpg", 
                 :overlay => "text:bold_dark:Sign up to see more",
                 :gravity => :center,  
                 :transformation => {:effect => "blur:500", :opacity => 50}) %>
Sometimes you want to blur only a certain region of an image. You can use the blur_region effect together with exact coordinates specified by x, y, width and height parameters. Here's an example that blurs only part of an uploaded screenshot:
 
 
 
Same example in Node.js:
cloudinary.image("front_face.jpg", { effect: "blur_region", x: 0, y: 0.5, w: 1.0 });
You can also automatically blur all faces detected in an image using Cloudinary's blur_faces. In the following example the face was automatically detected and blurred using the default level:
 
 
 
Same example in .NET:
string url = cloudinary.Api.UrlImgUp.Transform(
  new CloudinaryDotNet.Transformation().Effect("blur_faces")).BuildUrl("front_face.jpg");


Summary

Automatic image sharpening and blurring can do wonders to a website. For static assets, you can do that manually using your favorite image manipulation software. With Cloudinary such effects can be automatically applied to millions of user-uploaded images with ease. And if you decide to spruce up the graphical effects in your site's images, you can simply modify the transformation parameters in your development framework of choice. All images will be regenerated on the fly using the updated effect and will be served to your users optimized through a fast CDN.
 
It would be great if you try out the new filters and tell us when you think. If you don't have a Cloudinary account yet, you can create one for free.
 

Recent Blog Posts

An interview with Jason Grigsby about Responsive Images

In the conclusion of this three-part interview the Jason Grigsby, we examine what the future may hold for images on the web. Previously: Part 1, Part 2.

EP: I want to go back to the idea that we started with, that images are fundamentally complicated; that they’ll always present us with problems. What do you think we are going to be working on and talking about in five-to-10 years with regard to images?

Read more
Improve user experience with responsive websites and applications
This article originally appeared on Inc. Magazine and is reprinted with permission.

Back in the day, responsive website design wasn't the business imperative that it is now. In fact, just having a functioning website was all that it took to set you apart, and if it had images that loaded correctly within a few minutes, then that was a nice bonus. Needless to say, but I'll say it anyway, those days are long gone.
Read more
What to consider when developing media rich websites and apps
Websites have evolved greatly over the past few years. Once text-heavy websites have become more eye-catching with prominent images and video. But the addition of richer media isn’t the only change impacting websites. Consumer behavior also factors into this evolution, as web access has moved from the desktop realm to a variety of different devices – smartphones, tablets, laptops, smartwatches and TVs – with different dimensions and resolutions. And consumers want to be able to access web content anytime and from any location.
 
To ensure that website performance is optimized, bandwidth usage is minimized and users have a top-notch experience, we will need to address many challenges.

High resolution images and videos

If a picture is worth 1,000 words, it’s no surprise that website owners are using images and videos as powerful tools on their websites to engage visitors. High-resolution images look best, but these files are so big that they cause websites to load slowly and use excessive bandwidth. These problems frustrate visitors, and potentially decrease their incentive to  engage further on the website.
Read more
Plugin for automatic responsive images in Jekyll-generated sites

This is a guest post by Nicolas Hoizey, co-founder of Clever Age and creator of the Jekyll Cloudinary plugin. Nicolas’ plugin leverages Cloudinary’s image storage, optimization, resizing, and delivery infrastructures to automate responsive images in Jekyll-generated static sites. We think it’s the bee’s knees, and invited Nicolas to write a bit about the process and motivation behind it. Without further ado, here’s Nicolas.

Read more