Timur Kamaev

Convenient way to create post thumbnails on the fly without server overload.
The best alternative to scripts like “thumbnail.php”.
Supports Multisite.
<h3>Usage</h3>
The plugin for developers firstly, because it don’t do anything after install. In order to the plugin begin to work, you need use one of plugin function in your theme or plugin. Example:
<pre><code><?php echo kama_thumb_img( 'w=150 &h=150' ); ?>
</code></pre>
Using the code in the loop you will get ready thumbnail IMG tag. Plugin takes post thumbnail image or find first image in post content, resize it and create cache. Also creates custom field for the post with URL to original image. In simple words it cache all routine and in next page loads just take cache result.
You can make thumbs from custom URL, like this:
 
The <code>URL_TO_IMG</code> must be from local server: by default, plugin don’t work with external images, because of security. But you can set allowed hosts on settings page: <code>Settings > Media</code>.
All plugin functions:
<pre><code>// return thumb url URL
echo kama_thumb_src( $args, $src );

// return thumb IMG tag
echo kama_thumb_img( $args, $src );

// return thumb IMG tag wraped with <a>. A link of A will leads to original image.
echo kama_thumb_a_img( $args, $src );

// to get image width or height after thumb creation
echo kama_thumb( $optname );
// ex:
echo '<img src="'. kama_thumb_src('w=200') .'" width="'. kama_thumb('width') .'" height="'. kama_thumb('height') .'" alt="" />';
</code></pre>
Parameters:
<ul>
<li>
$args (array/string) 
Arguments to create thumb. Accepts:
<ul>
<li>
w | width 
(int) desired width.
</li>
<li>
h | height 
(int) desired height.
if parameters <code>w</code> and <code>h</code> not set, both of them became 100 – square thumb 100х100 px.
</li>
<li>
notcrop 
(isset) if set <code>crop</code> parameter become false – <code>crop=false</code>.
</li>
<li>
crop 
(isset) Control image cropping. By default always <code>true</code>.
To disable cropping set here <code>false/0/no/none</code> or set parameter <code>'notcrop'</code>. Then image will not be cropped and will be created as small copy of original image by sizes settings of one side: width or height – here plugin select the smallest suitable side. So one side will be as it set in <code>w</code> or <code>h</code> and another side will be smaller then <code>w</code> or <code>h</code>.
Cropping position
Also, you can specify string: <code>'top'</code>, <code>'bottom'</code>, <code>'left'</code>, <code>'right'</code> or <code>'center'</code> and any other combinations of this strings glued with <code>/</code>. Ex: <code>'right/bottom'</code>. All this will set cropping area:
<ul>
<li><code>'left', 'right'</code> – horizontal side (w)</li>
<li><code>'top', 'bottom'</code> – vertical side (h)</li>
<li><code>'center'</code> – for both sides (w and h)</li>
</ul>
When only one value is set, the other will be by default. By default: <code>'center/center'</code>.
Examples:
<pre><code>// image will be reduced by height, and width will be cropped.
// "right" means that right side of image will be shown and left side will be cut.
kama_thumb_img('w=200 &h=400 &crop=right');

// image will be redused by width, and height will be cropped.
// "top" means that the top of the image will be shown and bottom side will be cut.
kama_thumb_img('w=400 &h=200 &crop=top');

// you can specify two side position at once, order doesn't matter
kama_thumb_img('w=400 &h=200 &crop=top/right');
</code></pre>
Reduce image by specified side
In order to get not cropped proportionally rediced image by specified side: by width or height. You need specify only width or only height, then other side will be reduced proportional. And no cropping will appear here.
<pre><code>kama_thumb_img('w=200');
</code></pre>
So, width of our image will be 200, and height will be as it will… 
Теперь ширина всегда будет 200, а высота какая получится… And the picture will be always full, without cropping.
</li>
<li>
q | quality 
(int) jpg compression quality (Default 85. max.100)
</li>
<li>
stub_url 
(string) URL to no_photo image.
</li>
<li>
alt 
(str) alt attr of img tag.
</li>
<li>
title 
(str) title attr of img tag.
</li>
<li>
class 
(str) class attr of img tag.
</li>
<li>
style 
(str) style attr of img tag.
</li>
<li>
attr 
(str) Allow to pass any attributes in IMG tag. String passes in IMG tag as it is, without escaping.
</li>
<li>
a_class 
(str) class attr of A tag.
</li>
<li>
a_style 
(str) style attr of A tag.
</li>
<li>
a_attr 
(str) Allow to pass any attributes in A tag. String passes in A tag as it is, without escaping.
</li>
<li>
no_stub 
(isset) don’t show picture stub if there is no picture. Return empty string.
</li>
<li>
yes_stub 
(isset) show picture stub if global option in option disable stub showing, but we need it…
</li>
<li>
post_id | post 
(int|WP_Post) post ID. It needs when use function not from the loop. If pass the parameter plugin will exactly knows which post to process. Parametr ‘post’ added in ver 2.1.
</li>
<li>
attach_id 
(int) ID of wordpress attachment image. Also, you can set this parametr by pass attachment ID to ‘$src’ parament – second parametr of plugin functions: <code>kama_thumb_img('h=200', 250)</code> or <code>kama_thumb_img('h=200 &attach_id=250')</code>
</li>
<li>
allow 
(str) Which hosts are allowed. This option sets globally in plugin setting, but if you need allow hosts only for the function call, specify allow hosts here. Set ‘any’ to allow to make thumbs from any site (host).
</li>
</ul>
</li>
<li>
$src 
(string) URL to any image. In this case plugin will not parse URL from post thumbnail/content/attachments.
If parameters passes as array second argument <code>$src</code> can be passed in this array, with key: <code>src</code> или <code>url</code> или <code>link</code> или <code>img</code>:
<pre><code> echo kama_thumb_img( array(
 'src' => 'http://yousite.com/IMAGE_URL.jpg',
 'w' => 150,
 'h' => 100,
 ) );
</code></pre>
</li>
</ul>
<h3>Notes</h3>
<ol>
<li>
You can pass <code>$args</code> as string or array:
<pre><code> // string
 kama_thumb_img('w=200 &h=100 &alt=IMG NAME &class=aligncenter', 'IMG_URL');

 // array
 kama_thumb_img( array(
 'width' => 200,
 'height' => 150,
 'class' => 'alignleft'
 'src' => ''
 ) );
</code></pre>
</li>
<li>
You can set only one side: <code>width</code> | <code>height</code>, then other side became proportional.
</li>
<li><code>src</code> parameter or second function argument is for cases when you need create thumb from any image not image of WordPress post.</li>
<li>
For test is there image for post, use this code:
<pre><code> if( ! kama_thumb_img('w=150&h=150&no_stub') )
 echo 'NO img';
</code></pre>
</li>
</ol>
<h3>Examples</h3>
<h4>#1 Get Thumb</h4>
In the loop where you need the thumb 150х100:
<pre><code><?php echo kama_thumb_img('w=150 &h=100 &class=alignleft myimg'); ?>
</code></pre>
Result:
<pre><code><img src='thumbnail_URL' alt='' class='alignleft myimg' width='150' height='100'>
</code></pre>
<h4>#2 Not show stub image</h4>
<pre><code><?php echo kama_thumb_img('w=150 &h=100 &no_stub'); ?>
</code></pre>
<h4>#3 Get just thumb URL</h4>
<pre><code><?php echo kama_thumb_src('w=100&h=80'); ?>
</code></pre>
Result: <code>/wp-content/cache/thumb/ec799941f_100x80.png</code>
This url you can use like:
<pre><code><img src='<?php echo kama_thumb_src('w=100 &h=80 &q=75'); ?>' alt=''>
</code></pre>
<h4>#4 <code>kama_thumb_a_img()</code> function</h4>
<pre><code><?php echo kama_thumb_a_img('w=150 &h=100 &class=alignleft myimg &q=75'); ?>
</code></pre>
Result:
<pre><code><a href='ORIGINAL_URL'><img src='thumbnail_URL' alt='' class='alignleft myimg' width='150' height='100'></a>
</code></pre>
<h4>#5 Thumb of any image URL</h4>
Pass arguments as array:
<pre><code><?php
 echo kama_thumb_img( array(
 'src' => 'http://yousite.com/IMAGE_URL.jpg',
 'w' => 150,
 'h' => 100,
 ) );
?>
</code></pre>
Pass arguments as string:
<pre><code><?php
 echo kama_thumb_img('w=150 &h=200 ', 'http://yousite.com/IMAGE_URL.jpg');
?>
</code></pre>
When parameters passes as string and “src” parameter has additional query args (“src=$src &w=200” where $src = http://site.com/img.jpg?foo&foo2=foo3) it might be confuse. That’s why “src” parameter must passes as second function argument, when parameters passes as string (not array).
<h4>#6 Parameter post_id</h4>
Get thumb of post ID=50:
<pre><code><?php echo kama_thumb_img("w=150 &h=100 &post_id=50"); ?>
</code></pre>
<h3>I don’t need plugin</h3>
This plugin can be easily used not as a plugin, but as a simple php file.
If you are themes developer, and need all it functionality, but you need to install the plugin as the part of your theme, this short instruction for you:
<ol>
<li>Create folder in your theme, let it be ‘thumbmaker’ – it is for convenience.</li>
<li>Download the plugin and copy the files: <code>class.Kama_Make_Thumb.php</code> and <code>no_photo.jpg</code> to the folder you just create.</li>
<li>Include <code>class.Kama_Make_Thumb.php</code> file into theme <code>functions.php</code>, like this: 
require ‘thumbmaker/class.Kama_Make_Thumb.php’;</li>
<li>Bingo! Use functions: <code>kama_thumb_*()</code> in your theme code.</li>
<li>If necessary, open <code>class.Kama_Make_Thumb.php</code> and edit options (at the top of the file): cache folder URL/PATH, custom field name etc.</li>
</ol>
<ul>
<li>Conditions of Use – mention of this plugin in describing of your theme.</li>
</ul>

Kama Thumbnail

Great plugin! Allows you to save space on hosting and speeds up the site. The author quickly reacts and modifies the plugin. Thank you!

Must have

Попробовал на одном огромном портале с несколькими миллионами картинок - результта превзошел все мои ожидания.

Количество фоток на сервере стало заметно меньше (а размеров у нас очень много) и делать руками приходится не так много работы.

Спасибо!

Пожалуй, лучший плагин для создания тумбочек у постов

Creates post thumbnails on fly and cache the result. Auto-create of post thumbnails based on: WP post thumbnail OR first img in post content OR attach …

benplum

Presswell

Presswell Art Direction gives editors and developers a consistent way to manage image sizing and cropping in WordPress. Define custom sizes, set focal points, and generate non-core thumbnails only when they are actually needed.
Features
<ul>
<li>Control image cropping with focal points</li>
<li>Define custom image sizes and nested thumbnail variants</li>
<li>Select custom image sizes directly in the WordPress editor</li>
<li>Dynamically generate non-core thumbnails on demand</li>
<li>Run batch regeneration from a dedicated Media tool</li>
<li>Use Endpoint Mode when filename-based 404 handoff is unavailable</li>
<li>Import/export size definitions and migrate legacy focal-point metadata</li>
</ul>
Focal Point Cropping
Set a focal point for Media Library images to control how custom crops are framed. Mark the visual subject once, and generated thumbnails stay centered on the correct area.
Custom Size Management
Use the settings UI to define and edit custom image sizes. Registered sizes become available when inserting images in the block editor and classic editor workflows.
Dynamic Generation + Endpoint Mode
Presswell Art Direction avoids generating every custom size at upload time. WordPress core sizes are generated normally, while custom sizes are generated when requested in templates or by URL.
If filename-based 404 image requests do not reach WordPress (common in some NGINX/server setups), enable Endpoint Mode (<code>/pwad-image/?id=...&size=...</code>). The plugin includes an automatic compatibility check in wp-admin.
Regenerator
The Regenerator screen (Media -> Regenerate Thumbnails) builds a queue and processes images in batches, with progress metrics and retry handling for failed jobs. You can choose exactly which sizes should be regenerated.
<h4>Documentation</h4>
Public APIs
pwad_add_image_size( $args )
<ul>
<li>$args (array) (required) – Keyed array containing <code>name</code>, <code>key</code>, <code>height</code>, <code>width</code>, <code>crop</code> (optional), and optionally <code>thumbnails</code> values.</li>
<li>Thumbnail keys are prefixed with parent’s key like <code>[size]-[thumbnail]</code>.</li>
</ul>
Example:
<pre><code>pwad_add_image_size( array(
 'name' => 'Square',
 'key' => 'square',
 'width' => '1200',
 'height' => '1200',
 'crop' => true,
 'thumbnails' => array(
 array(
 'name' => 'Medium',
 'key' => 'medium',
 'width' => '800',
 'height' => '800',
 ),
 array(
 'name' => 'Small',
 'key' => 'small',
 'width' => '400',
 'height' => '400',
 ),
 ),
) );
</code></pre>
pwad_get_image_sizes()
Returns all currently-available sizes (WordPress defaults + plugin/theme sizes + Presswell Art Direction sizes/thumbnails).
Example:
$sizes = pwad_get_image_sizes();
pwad_get_image( $attachment_ID, $size_key, $attr = array() )
<ul>
<li>$attachment_ID (int) (required) – ID of image attachment</li>
<li>$size_key (string) (required) – Image size identifier (<code>thumbnail</code>, <code>large</code>, <code>my-size</code>, <code>my-size-mobile</code>, etc.)</li>
<li>$attr (array) (optional) – HTML attributes passed to the rendered image element</li>
</ul>
Returns an image tag.
Example:
$square_large = pwad_get_image( $img_ID, ‘square’ ); 
 $square_small = pwad_get_image( $img_ID, ‘square-small’, array( ‘class’ => ‘hero-image’ ) );
pwad_get_image_src( $attachment_ID, $size_key )
<ul>
<li>$attachment_ID (int) (required) – ID of image attachment</li>
<li>$size_key (string) (required) – Image size identifier (<code>thumbnail</code>, <code>large</code>, <code>my-size</code>, <code>my-size-mobile</code>, etc.)</li>
</ul>
Returns a keyed array containing the <code>file</code>, <code>url</code>, <code>path</code>, <code>height</code>, <code>width</code>, and <code>mime-type</code> values.
Example:
$square_large = pwad_get_image_src( $img_ID, ‘square’ ); 
 $square_small = pwad_get_image_src( $img_ID, ‘square-small’ );
Actions
pwad/image_generated
Fires immediately after a custom crop file is generated so themes/plugins can queue optimizers or post-processing.
Arguments:
<ul>
<li>$data[‘attachment_id’] (int) – Attachment ID.</li>
<li>$data[‘size_key’] (string) – Requested size key.</li>
<li>$data[‘size_data’] (array) – Registered/requested size definition used for generation.</li>
<li>$data[‘source_file’] (string) – Source file path from attachment metadata (relative upload path).</li>
<li>$data[‘generated_file’] (string) – Generated filename for the new crop.</li>
</ul>
Example:
add_action( ‘pwad/image_generated’, function( $data ) { 
 // Example: queue optimization when a new crop is created. 
 if ( ! empty( $data[‘attachment_id’] ) && ! empty( $data[‘generated_file’] ) ) { 
 do_action( ‘my_optimizer/queue’, $data ); 
 } 
 } );
WP-CLI
wp pwad regenerate
Regenerates thumbnails.
<ul>
<li><code>--queue-per-page=<int></code> (default <code>200</code>)</li>
<li><code>--batch-size=<int></code> (default <code>25</code>)</li>
<li><code>--target-seconds=<float></code> (default <code>5</code>)</li>
<li><code>--resume-last=<0|1></code> (default <code>0</code>, continue the last interrupted queue)</li>
</ul>
wp pwad cache-prime
Generates thumbnails based on sitemap.
<ul>
<li><code>--sitemap=<url></code> (optional, auto-detects from robots.txt/common sitemap endpoints)</li>
<li><code>--page-limit=<int></code> (default unlimited)</li>
<li><code>--image-limit=<int></code> (default unlimited)</li>
<li><code>--delay-ms=<int></code> (default <code>250</code>)</li>
<li><code>--timeout=<float></code> (default <code>10</code>)</li>
<li><code>--retries=<int></code> (default <code>2</code>)</li>
<li><code>--include-external=<0|1></code> (default <code>0</code>)</li>
<li><code>--force-endpoint=<0|1></code> (default <code>0</code>)</li>
<li><code>--report-csv=<path></code> (optional, writes per-URL status/error report)</li>
<li><code>--dry-run=<0|1></code> (default <code>0</code>)</li>
<li><code>--resume-last=<0|1></code> (default <code>0</code>, continue the last interrupted prime run)</li>
</ul>
wp pwad cache-prune
Deletes cached thumbnails not referenced in sitemap.
<ul>
<li><code>--sitemap=<url></code> (optional, auto-detects from robots.txt/common sitemap endpoints)</li>
<li><code>--batch-size=<int></code> (default <code>200</code>)</li>
<li><code>--max-images=<int></code> (default unlimited)</li>
<li><code>--page-limit=<int></code> (default unlimited)</li>
<li><code>--image-limit=<int></code> (default unlimited)</li>
<li><code>--timeout=<float></code> (default <code>10</code>)</li>
<li><code>--grace-days=<int></code> (default <code>0</code>, uses file modified time)</li>
<li><code>--include-external=<0|1></code> (default <code>0</code>)</li>
<li><code>--force-endpoint=<0|1></code> (default <code>0</code>)</li>
<li><code>--report-csv=<path></code> (optional, writes per-file keep/delete report)</li>
<li><code>--dry-run=<0|1></code> (default <code>1</code>)</li>
<li><code>--resume-last=<0|1></code> (default <code>0</code>, continue the last interrupted prune run)</li>
</ul>
wp pwad cache-clean
Deletes all cached thumbnails.
<ul>
<li><code>--batch-size=<int></code> (default <code>200</code>)</li>
<li><code>--max-images=<int></code> (default unlimited)</li>
<li><code>--include-default=<0|1></code> (default <code>0</code>)</li>
<li><code>--dry-run=<0|1></code> (default <code>1</code>)</li>
<li><code>--resume-last=<0|1></code> (default <code>0</code>, continue the last interrupted clean run)</li>
</ul>
wp pwad queue-status
Shows resumable/remaining state for regenerator and cache queue runs.
<h3>Privacy</h3>
Presswell Art Direction does not send image data to external services. It processes image metadata and generated variants within your WordPress environment.

Presswell Art Direction

Really easy to use, and integrated perfectly with the front end of the site without any extra javascript or CSS required. Perfect add-on.

Very well done

Manage focal-point cropping and on-demand custom image generation in WordPress.

Kama Thumbnail vs Presswell Art Direction