michele.settembre

This plugin was created to make easier the life of people that want to get pictures, images, photos from the web, rather than download your image on your computer and, then, upload it in your media library, you can paste the image url in the field and get it from the web straight in your media library. Afterword you can click to set the post thumbnail and you will find the aquired image in your media library, ready to be inserted in your post.
This plugin is a simple box, activate the plugin, follow the settings link, activate the option to see the new form in the post thumbnail metabox in the post edit page and it’s done!
I created this plugin mainly for me, when I was creating websites I incurred the need to quickly grab some of my photos from another website ands that was the reason of this idea, it is something like creating a tunnel from one site to another to transfer images.

Post Thumbnail from URL

Post Thumbnail From URL is a plugin to quickly import images from the web straight to your Media Library using a public URL.

Fabien Quatravaux

Sometimes, your website design requires to turn pictures in black & white : for example in a gallery display, you can have all thumbnails in grayscale and bring up colors when the mouse is hovering it. 
This plugin will make it possible without the need to manualy create the grayscale variant of each picture.
In your theme’s <code>functions.php</code>, instead of using WP <a href="https://codex.wordpress.org/Function_Reference/add_image_size" rel="nofollow ugc">add_image_size</a> function, use <code>grayscale_add_image_size('custom_size', xxx, yyy, $crop, $grayscale)</code> (with <code>$crop</code> set to <code>true</code> if you want to crop the image, and <code>$grayscale</code> set to <code>true</code> if you want a grayscale version of the image). Then, you can use <a href="https://codex.wordpress.org/Function_Reference/the_post_thumbnail" rel="nofollow ugc">the_post_thumbnail</a> or any thumbnail function to get your grayscale image :
<pre><code>the_post_thumbnail('custom_size-gray')
</code></pre>
A gamma correction is applied automatically to make the black & white pictures look good. From version 1.2, You can tune this gamma correction with the <code>grayscale_gamma_correction</code> filter. Your filter would have to return a float number that will be use as the <code>outputgamma</code> parameter of the <a href="http://php.net/manual/fr/function.imagegammacorrect.php" rel="nofollow ugc">imagegammacorrect</a> function.
<h4>Known bugs</h4>
<ul>
<li>Grayscale images are not generated when the original image size is smaller than the specified thumbnail size.</li>
</ul>

Grayscale

Automatically create grayscale thumbnails for a given image size.

Post Thumbnail from URL vs Grayscale