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Archive for June 2012

Cloud-based API for applying effects on images

Jun 18, 2012 by Nadav Soferman
Tags: Feature, Image-transformation, Ruby-on-Rails, Django, PHP

If you Google for “Hello Cloudinary”, you will find some intriguing articles claiming that Cloudinary is a Photoshop replacement. Well, although the comparison is very flattering and we do believe that Cloudinary is a fantastic service for web developers, we never thought of our service as a replacement for Photoshop. However, some image manipulation features of Cloudinary allow web developers and web designers to dynamically modify the look & feel of their website’s images in an extremely easy way without manually processing their images using an image editing desktop software. In this blog post we wanted to describe some of Cloudinary’s newest features - applying effects and filters on images.

Effects 

Applying effects on images is done using the new ‘effect’ parameter or ‘e’ for URLs. Some effects also accept an additional numeric parameter. Here are some examples:

Let’s take the following ‘horses’ image that was uploaded to Cloudinary:

http://res.cloudinary.com/demo/image/upload/horses.jpg

The following examples modify the color saturation of the image. A negative saturation value will reduce saturation and a positive will increase it:

.../image/upload/e_saturation:-70/horses.jpg       .../image/upload/e_saturation:70/horses.jpg

   

If you’re using Cloudinary’s client-side integration libraries, applying this transformation is made even simpler:

Ruby on Rails:

<%= cl_image_tag("horses.jpg", :effect => "saturation:70") %>

PHP:

<?php echo cl_image_tag("horses.jpg", array("effect" => "saturation:70")) ?>
Django:
{% cloudinary "horses.jpg" effect="saturation:70" %}

 

With Cloudinary’s cloud-based transformations you can also change an image’s brightness: 

.../image/upload/e_brightness:-50/horses.jpg      .../image/upload/e_brightness:50/horses.jpg

   

 
You can also apply a sepia effect. Use either the default sepia level or set a custom level by specifying the extra numeric value:
 
 
And you can also easily convert an image to grayscale or apply an oil-paint effect:
 

 

Chained Transformations

If you read our documentation and follow our blog posts, you probably know that Cloudinary already provides many image transformations and delivery methods. By chaining these image transformations together, you can create images that perfectly complement your graphic design.

For example, the following image is Arianna Huffington’s Facebok profile picture:

Take a look at the following Cloudinary URL that generates the image below:

.../image/facebook/w_150,h_150,c_thumb,g_face,r_20,e_sepia/l_techcrunch,g_south_west,x_5,y_5,w_50/a_10/AriannaHuffington.png 

 

What happened here? Simply accessing the above URL told Cloudinary to remotely fetch Arriana Huffington’s Facebook profile picture, created a 150x150px thumbnail using face detection based cropping, rounded the image’s corners, added a sepia effect, converted it to a transparent PNG format, added a watermark layer on the bottom-left corner, rotated the image by 10 degrees clock-wise and ultimately delivered the resulting image through a fast CDN using smart caching techniques. Isn’t that great?

Same example in Ruby on Rails:

<%= facebook_profile_image_tag("AriannaHuffington.png", :angle => 10, 
        :transformation => 
          [{:width => 150, :height => 150, :crop => :thumb, 
            :gravity => :face, :radius => 20, :effect => :sepia},
           {:overlay => "techcrunch", :gravity => :south_west, 
            :x => 5, :y => 5, :width => 50}]) %>

 

Tweaking a Website’s Color Scheme

Web developers and web designers often encounter a scenario in which a client sees their website and asks for just a tiny tweak to the color scheme they used. Changing colors of texts and other HTML elements can be easily done using CSS tweaks. But what about the images that construct your website’s design? With Cloudinary you no longer need to process all images to generate slightly different color variations. You can simply apply the hue change effect on all images delivered by Cloudinary. It accepts a numeric value between -100 and 100.

For example, the following is a background image used on Cloudinary’s web site.



<img src="site_bg.jpg" width="350" height="135" data-src="site_bg.jpg" 
     class="bg_image"/>

The following URL can be used to generate a version with a slightly different hue:



The same can be achieved using Cloudinary’s client-side libraries. For example, this is how it might look like using our jQuery library:
$('.bg_image').cloudinary({ effect: "hue:50"});

All effects and filters described above are available for all our paid and free plans. Want to try it out? Sign up to our free plan in seconds.
Please tell us what you think about the new effects. Should we support additional effects? Any other image transformation features still missing?

Automatic and custom image rotation

Jun 13, 2012 by Itai Lahan
Tags: Feature, Image-transformation
Several years ago, a good friend of mine showed me a cool graphic design concept for his new web-based startup company. It looked pretty great. What really caught my eye was the designer’s unique use of visitor profile photos. You see, when a visitor registered to the service and uploaded his photo, the designer envisioned a large, faded, B&W, slightly rotated version of the same profile photo being used as the background image for the visitor’s personal home page. I thought for a minute and told my friend to let this one go. 
 
While the effect looked great, installing a server-side image manipulation software just for the creation of a background photo seemed like an excessive effort for an early-stage, self-funded startup. I still have mixed feelings about this particular piece of advice. Today, I have a chance to make some right out of this wrong, with the addition of image rotation to Cloudinary’s cloud-based image manipulation capabilities. If we had Cloudinary back then, applying these effects to an image while rotating it would have been a no brainer. 
 
In order to rotate an image, simply use the new 'angle' parameter, or 'a' for URL based transformations. It accepts an integer of either positive or negative number of degrees to rotate the image by.
 
The following example rotates an uploaded image by 25 degrees clockwise in addition to resizing it to 30% of the original size:
 


    
 
Same example in Ruby on Rails:
<%= cl_image_tag("sheep.jpg", :width => 0.3, :crop => :scale, :angle => 25) %>
In PHP:
<?php echo cl_image_tag("sheep.jpg", array("width" => 0.3, "crop" => "scale",
                        "angle" => 25)); ?>
 
And with our jQuery plugin:
$.cloudinary.image("sheep.jpg", {width: 0.3, crop: "scale", angle: 25});
 
 
You can also chain multiple transformations to reach nicer effects. As always, this can be achieved using either a simple URL or a one-liner piece of code with your preferred Cloudinary client-side library. The following example scales down the uploaded image, rounds its corners, adds a watermark and rotates the image by 15 degrees counter-clockwise:
 


Automatic image rotation

Real-world photos usually have a clear orientation. Occasionally, you’ll run into image that can be depicted just fine in both landscape and portrait modes. One example might be an architectural floor plan or a design for an apartment. Let’s see how such images might fit a graphic design that leaves room for 300x200px photos.
 


  

As you can see the landscape plan fits almost perfectly into the 300x200 rectangle. However, the portrait one on the right doesn’t effectively use the given space and requires lots of padding on its right and left sides.
 
Such drawings are oblivious to orientation and hence we can rotate them without affecting their content. For such images, we can get a perfect fit by letting Cloudinary automatically rotate the image, when needed. Simply pass 'auto' (or 'auto_right') and 'auto_left' as the 'angle' parameter. This parameter tells Cloudinary that it can rotate the image left or right when the aspect ratio of the original image doesn’t match the requested target ratio.
 
Here’s the same example, this time with auto rotation:
 
 

  
 
As you can see, the result is a much better display of the drawing, with considerably less padding required. All that, without any effort or coding on your side.
 
Same example in Ruby on Rails:
<%= cl_image_tag("portrait_plan.jpg", :width => 300, :height => 200, 
                 :crop => :pad, :background => '#cddae4', :angle => :auto) %>
If you use CarrierWave in your a Rails project, you can add the following to your versions:
cloudinary_transformation :angle => :auto
View The SpaceIncidentally, we saw the need for auto-rotated images at the website of one of Cloudinary’s customers. The service, View The Space, a smart online tool that helps generate leasing activity for landlords and brokers, embeds such architectural designs and floor plans within its website.
 
Custom and automatic image rotation are now available for our free and paid plans. Note that although some samples above are in Ruby, the same can be done in other Cloudinary client libraries - PHP, Python & Django, Perl, .NET and jQuery.
 
If you enjoyed our new image rotation capabilities, make sure you check out Coudinary’s face detection based cropping, corners rounding and watermarks overlays.