On the fly image resizer / cropper / grayscaler / colorizer / opacitor :) for WordPress

Update: BFI Thumb now integrates into the core WordPress image functions, you actually don't have to call bfi_thumb to use it!

You can read the tutorial and get more information about BFI_Thumb from this article: Moving Away From TimThumb to BFIThumb

Supports WordPress 3.5+

Bfi_thumb resizes image on the fly using WordPress' Image Editor classes, thus supports both Imagick and GD and switches automatically depending on what's available. The default Image Editors only have a handful of basic functions (crop, resize, rotate, etc), bfi_thumb also extends these classes to include these new functions:

• Grayscale
• Color (colorize)
• Opacity
• Negate
• Resize images down or UP

The code was inspired by the awesome Aqua Resizer

You can use this script in your WordPress themes or plugins. The script is safe to be included multiple times in a single WordPress site by different plugins and themes. When multiple versions of BFI_Thumb are found within a site, the newest version will be used.

This means that if you use bfi_thumb in your WordPress theme, and some plugins you also have activated use bfi_thumb, they would all work without any problems.

My themes usee BFI Thumb to generate all it's images:

• MaS WP Theme
• Amplus WP Theme
• Dimension WP Theme

Bfi_thumb stores previously created images in WP's default uploads directory in the subdirectory bfi_thumb, and uses those for future calls. The script automatically checks for updates on the original image then re-creates new images when needed. Any image can be used as long it is in your WordPress instance. Remote images are not supported due to security concerns.

You can change the location of where the images are saved by defining this constant anywhere in your code:

// Change the upload subdirectory to wp-content/uploads/other_dir
@define( BFITHUMB_UPLOAD_DIR, 'other_dir' );

Aqua Resizer is awesome, WP's Image Editor is awesome, Timthumb is awesome.

When WP reached 3.5 and introduced the Image Editor class, as a theme author I couldn't anymore use Timthumb in my WP themes. An alternative was to use Aqua Resizer instead. Although it did the job quite well, I needed some of the functionalities supported by Timthumb.. I needed to be allowed to grayscale, color tint images and change the opacity of images all while resizing them. I couldn't find anything that did everything I wanted, so I made BFI_Thumb.

Use this if your image can be accessed by WP functions such as the_post_thumbnail

1. Include / require BFI_Thumb.php into your WordPress files.

require_once('BFI_Thumb.php');

2. Call your normal WordPress image functions, specify an array as the $size of your image, then add a parameter 'bfi_thumb' => true to it.

// Getting the featured image without bfi_thumb
the_post_thumbnail( array( 1024, 400 ) );

// With bfi_thumb
the_post_thumbnail( array( 1024, 400, 'bfi_thumb' => true ) );

// With bfi_thumb & with parameters
the_post_thumbnail( array( 1024, 400, 'bfi_thumb' => true, 'grayscale' => true ) );

// Getting an attachment image with bfi_thumb & multiple parameters
$params = array( 400, 300, 'opacity' => 50, 'grayscale' => true, 'colorize' => '#ff0000' );
wp_get_attachment_image_src( $attachment_id, $size )

This method can be used also in other WordPress image functions that accept a $size parameter.

Use this if your image cannot be accessed by WP functions such as the_post_thumbnail

1. Include / require BFI_Thumb.php into your WordPress files.

require_once('BFI_Thumb.php');

2. Call the function to get the image URL

$params = array( 'width' => 400 );
echo "<img src='" . bfi_thumb( "URL-to-image.jpg", $params ) . "'/>";

$params is an associative array containing the actions to perform on your image.

Examples:

// Resize by width only
$params = array( 'width' => 400 );
bfi_thumb( "URL-to-image.jpg", $params );

// Resize by width and height
$params = array( 'width' => 400, 'height' => 300 );
bfi_thumb( "URL-to-image.jpg", $params );

// Crop
$params = array( 'width' => 400, 'height' => 300, 'crop' => true );
bfi_thumb( "URL-to-image.jpg", $params );

// Change opacity (makes your image into a PNG)
$params = array( 'opacity' => 80 ); // 80% opaque
bfi_thumb( "URL-to-image.jpg", $params );

// Grayscale
$params = array( 'grayscale' => true );
bfi_thumb( "URL-to-image.jpg", $params );

// Colorize
$params = array( 'color' => '#ff0000' );
bfi_thumb( "URL-to-image.jpg", $params );

// Negate
$params = array( 'negate' => true );
bfi_thumb( "URL-to-image.jpg", $params );

// Multiple parameters
$params = array( 'width' => 400, 'height' => 300, 'opacity' => 50, 'grayscale' => true, 'colorize' => '#ff0000' );
bfi_thumb( "URL-to-image.jpg", $params );

v1.3

• Now integrates in WordPress image functions

v1.2.1

• Fixed T_PAAMAYIM_NEKUDOTAYIM error in PHP 5.2.x

GPL 3.0

It's not required but I appreciate if you attribute and/or link back if you find this helpful :)

Twitter: @bfintal & @gambitph

Google+: +Benjamin Intal