BFI_Thumb.php

<?php
/*
 * bfi_thumb - WP Image Resizer v1.3
 *
 * (c) 2013 Benjamin F. Intal / Gambit
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/** Uses WP's Image Editor Class to resize and filter images
 *
 * @param $url string the local image URL to manipulate
 * @param $params array the options to perform on the image. Keys and values supported:
 *          'width' int pixels
 *          'height' int pixels
 *          'opacity' int 0-100
 *          'color' string hex-color #000000-#ffffff
 *          'grayscale' bool
 *          'negate' bool
 *          'crop' bool
 * @param $single boolean, if false then an array of data will be returned
 * @return string|array containing the url of the resized modofied image
 */

if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly

if ( !function_exists( 'bfi_thumb' ) ) {
function bfi_thumb($url, $params = array(), $single = true) {
    $class = BFI_Class_Factory::getNewestVersion( 'BFI_Thumb' );
    return call_user_func( array( $class, 'thumb' ), $url, $params, $single );
}
}


/**
 * Class factory, this is to make sure that when multiple bfi_thumb scripts
 * are used (e.g. a plugin and a theme both use it), we always use the
 * latest version.
 */
if ( !class_exists( 'BFI_Class_Factory' ) ) {
class BFI_Class_Factory {
    public static $versions = array();
    public static $latestClass = array();

    public static function addClassVersion( $baseClassName, $className, $version ) {
        if ( empty( self::$versions[$baseClassName] ) ) {
            self::$versions[$baseClassName] = array();
        }
        self::$versions[$baseClassName][] = array(
            'class' => $className,
            'version' => $version
        );
    }

    public static function getNewestVersion( $baseClassName ) {
        if ( empty( self::$latestClass[$baseClassName] ) ) {
            usort( self::$versions[$baseClassName], array( __CLASS__, "versionCompare" ) );
            self::$latestClass[$baseClassName] = self::$versions[$baseClassName][0]['class'];
            unset( self::$versions[$baseClassName] );
        }
        return self::$latestClass[$baseClassName];
    }

    public static function versionCompare( $a, $b ) {
        return version_compare( $a['version'], $b['version'] ) == 1 ? -1 : 1;
    }
}
}



/*
 * Change the default image editors
 */
add_filter('wp_image_editors', 'bfi_wp_image_editor');

// Instead of using the default image editors, use our extended ones
if ( !function_exists( 'bfi_wp_image_editor' ) ) {
function bfi_wp_image_editor($editorArray) {
    // Make sure that we use the latest versions
    return array(
        BFI_Class_Factory::getNewestVersion( 'BFI_Image_Editor_GD' ),
        BFI_Class_Factory::getNewestVersion( 'BFI_Image_Editor_Imagick' ),
    );
}
}

require_once ABSPATH . WPINC . '/class-wp-image-editor.php';
require_once ABSPATH . WPINC . '/class-wp-image-editor-imagick.php';
require_once ABSPATH . WPINC . '/class-wp-image-editor-gd.php';



/**
 * check for ImageMagick or GD
 */
add_action('admin_init', 'bfi_wp_image_editor_check');
if ( !function_exists( 'bfi_wp_image_editor_check' ) ) {
function bfi_wp_image_editor_check() {
    $arg = array('mime_type' => 'image/jpeg');
    if (wp_image_editor_supports($arg) !== true) {
        add_filter('admin_notices', 'bfi_wp_image_editor_check_notice');
    }
}
}
if ( !function_exists( 'bfi_wp_image_editor_check_notice' ) ) {
function bfi_wp_image_editor_check_notice() {
    printf("<div class='error'><p>%s</div>",
        __("The server does not have ImageMagick or GD installed and/or enabled! Any of these libraries are required for WordPress to be able to resize images. Please contact your server administrator to enable this before continuing.", "default"));
}
}


/*
 * Enhanced Imagemagick Image Editor
 */
if ( !class_exists( 'BFI_Image_Editor_Imagick_1_3' ) ) {
BFI_Class_Factory::addClassVersion( 'BFI_Image_Editor_Imagick', 'BFI_Image_Editor_Imagick_1_3', '1.3' );

class BFI_Image_Editor_Imagick_1_3 extends WP_Image_Editor_Imagick {

    /** Changes the opacity of the image
     *
     * @supports 3.5.1
     * @access public
     *
     * @param float $opacity (0.0-1.0)
     * @return boolean|WP_Error
     */
    public function opacity($opacity) {
        $opacity /= 100;

        try {
            // From: http://stackoverflow.com/questions/3538851/php-imagick-setimageopacity-destroys-transparency-and-does-nothing
            // preserves transparency
            //$this->image->setImageOpacity($opacity);
            return $this->image->evaluateImage(Imagick::EVALUATE_MULTIPLY, $opacity, Imagick::CHANNEL_ALPHA);
        } catch ( Exception $e ) {
            return new WP_Error( 'image_opacity_error', $e->getMessage() );
        }
    }

    /** Tints the image a different color
     *
     * @supports 3.5.1
     * @access public
     *
     * @param string hex color e.g. #ff00ff
     * @return boolean|WP_Error
     */
    public function colorize($hexColor) {
        try {
            return $this->image->colorizeImage($hexColor, 1.0);
        } catch (Exception $e) {
            return new WP_Error( 'image_colorize_error', $e->getMessage() );
        }
    }

    /** Makes the image grayscale
     *
     * @supports 3.5.1
     * @access public
     *
     * @return boolean|WP_Error
     */
    public function grayscale() {
        try {
            return $this->image->modulateImage(100,0,100);
        } catch (Exception $e) {
            return new WP_Error( 'image_grayscale_error', $e->getMessage() );
        }
    }

    /** Negates the image
     *
     * @supports 3.5.1
     * @access public
     *
     * @return boolean|WP_Error
     */
    public function negate() {
        try {
            return $this->image->negateImage(false);
        } catch (Exception $e) {
            return new WP_Error( 'image_negate_error', $e->getMessage() );
        }
    }
}
}


/*
 * Enhanced GD Image Editor
 */
if ( !class_exists( 'BFI_Image_Editor_GD_1_3' ) ) {
BFI_Class_Factory::addClassVersion( 'BFI_Image_Editor_GD', 'BFI_Image_Editor_GD_1_3', '1.3' );

class BFI_Image_Editor_GD_1_3 extends WP_Image_Editor_GD {
    /** Rotates current image counter-clockwise by $angle.
     * Ported from image-edit.php
     * Added presevation of alpha channels
     *
     * @since 3.5.0
     * @access public
     *
     * @param float $angle
     * @return boolean|WP_Error
     */
    public function rotate( $angle ) {
        if ( function_exists('imagerotate') ) {
            $rotated = imagerotate( $this->image, $angle, 0 );

            // Add alpha blending
            imagealphablending($rotated, true);
            imagesavealpha($rotated, true);

            if ( is_resource( $rotated ) ) {
                imagedestroy( $this->image );
                $this->image = $rotated;
                $this->update_size();
                return true;
            }
        }
        return new WP_Error( 'image_rotate_error', __('Image rotate failed.', 'default'), $this->file );
    }

    /** Changes the opacity of the image
     *
     * @supports 3.5.1
     * @access public
     *
     * @param float $opacity (0.0-1.0)
     * @return boolean|WP_Error
     */
    public function opacity($opacity) {
        $opacity /= 100;

        $filtered = $this->_opacity($this->image, $opacity);

        if (is_resource($filtered)) {
            // imagedestroy($this->image);
            $this->image = $filtered;
            return true;
        }

        return new WP_Error( 'image_opacity_error', __('Image opacity change failed.', 'default'), $this->file );
    }

    // from: http://php.net/manual/en/function.imagefilter.php
    // params: image resource id, opacity (eg. 0.0-1.0)
    protected function _opacity($image, $opacity) {
        if (!function_exists('imagealphablending') ||
            !function_exists('imagecolorat') ||
            !function_exists('imagecolorallocatealpha') ||
            !function_exists('imagesetpixel')) return false;

        //get image width and height
        $w = imagesx( $image );
        $h = imagesy( $image );

        //turn alpha blending off
        imagealphablending( $image, false );

        //find the most opaque pixel in the image (the one with the smallest alpha value)
        $minalpha = 127;
        for ($x = 0; $x < $w; $x++) {
            for ($y = 0; $y < $h; $y++) {
                $alpha = (imagecolorat($image, $x, $y) >> 24 ) & 0xFF;
                if( $alpha < $minalpha ) {
                    $minalpha = $alpha;
                }
            }
        }

        //loop through image pixels and modify alpha for each
        for ( $x = 0; $x < $w; $x++ ) {
            for ( $y = 0; $y < $h; $y++ ) {
                //get current alpha value (represents the TANSPARENCY!)
                $colorxy = imagecolorat( $image, $x, $y );
                $alpha = ( $colorxy >> 24 ) & 0xFF;
                //calculate new alpha
                if ( $minalpha !== 127 ) {
                    $alpha = 127 + 127 * $opacity * ( $alpha - 127 ) / ( 127 - $minalpha );
                } else {
                    $alpha += 127 * $opacity;
                }
                //get the color index with new alpha
                $alphacolorxy = imagecolorallocatealpha( $image, ( $colorxy >> 16 ) & 0xFF, ( $colorxy >> 8 ) & 0xFF, $colorxy & 0xFF, $alpha );
                //set pixel with the new color + opacity
                if(!imagesetpixel($image, $x, $y, $alphacolorxy)) {
                    return false;
                }
            }
        }

        imagesavealpha($image, true);

        return $image;
    }

    /** Tints the image a different color
     *
     * @supports 3.5.1
     * @access public
     *
     * @param string hex color e.g. #ff00ff
     * @return boolean|WP_Error
     */
    public function colorize($hexColor) {
        if (function_exists('imagefilter') &&
            function_exists('imagesavealpha') &&
            function_exists('imagealphablending')) {
            $hexColor = preg_replace('#^\##', '', $hexColor);
            $r = hexdec (substr ($hexColor, 0, 2));
            $g = hexdec (substr ($hexColor, 2, 2));
            $b = hexdec (substr ($hexColor, 2, 2));

            imagealphablending( $this->image, false );
            if (imagefilter($this->image, IMG_FILTER_COLORIZE, $r, $g, $b, 0)) {
                imagesavealpha($this->image, true);
                return true;
            }
        }
        return new WP_Error( 'image_colorize_error', __('Image color change failed.', 'default'), $this->file );
    }

    /** Makes the image grayscale
     *
     * @supports 3.5.1
     * @access public
     *
     * @return boolean|WP_Error
     */
    public function grayscale() {
        if (function_exists('imagefilter')) {
            if (imagefilter($this->image, IMG_FILTER_GRAYSCALE)) {
                return true;
            }
        }
        return new WP_Error( 'image_grayscale_error', __('Image grayscale failed.', 'default'), $this->file );
    }

    /** Negates the image
     *
     * @supports 3.5.1
     * @access public
     *
     * @return boolean|WP_Error
     */
    public function negate() {
        if (function_exists('imagefilter')) {
            if (imagefilter($this->image, IMG_FILTER_NEGATE)) {
                return true;
            }
        }
        return new WP_Error( 'image_negate_error', __('Image negate failed.', 'default'), $this->file );
    }
}
}


/*
 * Main Class
 */
if ( !class_exists( 'BFI_Thumb_1_3' ) ) {
BFI_Class_Factory::addClassVersion( 'BFI_Thumb', 'BFI_Thumb_1_3', '1.3' );

class BFI_Thumb_1_3 {
    /** Uses WP's Image Editor Class to resize and filter images
     * Inspired by: https://github.com/sy4mil/Aqua-Resizer/blob/master/aq_resizer.php
     *
     * @param $url string the local image URL to manipulate
     * @param $params array the options to perform on the image. Keys and values supported:
     *          'width' int pixels
     *          'height' int pixels
     *          'opacity' int 0-100
     *          'color' string hex-color #000000-#ffffff
     *          'grayscale' bool
     *          'crop' bool
     *          'negate' bool
     * @param $single boolean, if false then an array of data will be returned
     * @return string|array
     */
    public static function thumb($url, $params = array(), $single = true) {
        extract($params);

        //validate inputs
        if(!$url) return false;

        //define upload path & dir
        $upload_info = wp_upload_dir();
        $upload_dir = $upload_info['basedir'];
        $upload_url = $upload_info['baseurl'];
        $theme_url = get_template_directory_uri();
        $theme_dir = get_template_directory();

        // find the path of the image. Perform 2 checks:
        // #1 check if the image is in the uploads folder
        if(strpos( $url, $upload_url ) !== false) {
            $rel_path = str_replace( $upload_url, '', $url);
            $img_path = $upload_dir . $rel_path;

        // #2 check if the image is in the current theme folder
        } else if (strpos($url, $theme_url) !== false) {
            $rel_path = str_replace( $theme_url, '', $url);
            $img_path = $theme_dir . $rel_path;
        }

        // Fail if we can't find the image in our WP local directory
        if ( empty( $img_path ) ) return $url;

        //check if img path exists, and is an image indeed
        if( !@file_exists($img_path) OR !getimagesize($img_path) ) return $url;

        // This is the filename
        $basename = basename($img_path);

        //get image info
        $info = pathinfo($img_path);
        $ext = $info['extension'];
        list($orig_w,$orig_h) = getimagesize($img_path);

        // support percentage dimensions. compute percentage based on
        // the original dimensions
        if (isset($width)) {
            if (stripos($width, '%') !== false) {
                $width = (int)((float)str_replace('%', '', $width) / 100 * $orig_w);
            }
        }
        if (isset($height)) {
            if (stripos($height, '%') !== false) {
                $height = (int)((float)str_replace('%', '', $height) / 100 * $orig_h);
            }
        }

        // The only purpose of this is to detemine the final width and height
        // without performing any actual image manipulation, which will be used
        // to check whether a resize was previously done.
        if (isset($width)) {
            //get image size after cropping
            $dims = image_resize_dimensions($orig_w, $orig_h, $width, isset($height) ? $height : null, isset($crop) ? $crop : false);
            $dst_w = $dims[4];
            $dst_h = $dims[5];
        }

        // create the suffix for the saved file
        // we can use this to check whether we need to create a new file or just use an existing one.
        $suffix = (string)filemtime($img_path) .
            (isset($width) ? str_pad((string)$width, 5, '0', STR_PAD_LEFT) : '00000') .
            (isset($height) ? str_pad((string)$height, 5, '0', STR_PAD_LEFT) : '00000') .
            (isset($opacity) ? str_pad((string)$opacity, 3, '0', STR_PAD_LEFT) : '100') .
            (isset($color) ? str_pad(preg_replace('#^\##', '', $color), 8, '0', STR_PAD_LEFT) : '00000000') .
            (isset($grayscale) ? ($grayscale ? '1' : '0') : '0') .
            (isset($crop) ? ($crop ? '1' : '0') : '0') .
            (isset($negate) ? ($negate ? '1' : '0') : '0');
        $suffix = self::base_convert_arbitrary($suffix, 10, 36);

        // use this to check if cropped image already exists, so we can return that instead
        $dst_rel_path = str_replace( '.'.$ext, '', basename($img_path));

        // If opacity is set, change the image type to png
        if (isset($opacity)) $ext = 'png';


        // Create the upload subdirectory, this is where
        // we store all our generated images
        if ( defined( 'BFITHUMB_UPLOAD_DIR' ) ) {
            $upload_dir .= "/" . BFITHUMB_UPLOAD_DIR;
            $upload_url .= "/" . BFITHUMB_UPLOAD_DIR;
        } else {
            $upload_dir .= "/bfi_thumb";
            $upload_url .= "/bfi_thumb";
        }
        if ( !is_dir( $upload_dir ) ) {
            wp_mkdir_p( $upload_dir );
        }


        // desination paths and urls
        $destfilename = "{$upload_dir}/{$dst_rel_path}-{$suffix}.{$ext}";
        $img_url = "{$upload_url}/{$dst_rel_path}-{$suffix}.{$ext}";

        // if file exists, just return it
        if (@file_exists($destfilename) && getimagesize($destfilename)) {
        } else {
            // perform resizing and other filters
            $editor = wp_get_image_editor($img_path);

            if (is_wp_error( $editor )) return false;

            /*
             * Perform image manipulations
             */
            if ( ( isset( $width ) && $width ) || ( isset( $height ) && $height ) ) {
                if ( is_wp_error( $editor->resize( isset( $width ) ? $width : null, isset( $height ) ? $height : null, isset( $crop ) ? $crop : false ) ) ) {
                    return false;
                }
            }

            if ( isset( $negate ) ) {
                if ( $negate ) {
                    if ( is_wp_error( $editor->negate() ) ) {
                        return false;
                    }
                }
            }

            if ( isset( $opacity ) ) {
                if ( is_wp_error( $editor->opacity( $opacity ) ) ) {
                    return false;
                }
            }

            if ( isset( $grayscale ) ) {
                if ( $grayscale ) {
                    if ( is_wp_error( $editor->grayscale() ) ) {
                        return false;
                    }
                }
            }

            if ( isset( $color ) ) {
                if ( is_wp_error( $editor->colorize( $color ) ) ) {
                    return false;
                }
            }

            // save our new image
            $mime_type = isset( $opacity ) ? 'image/png' : null;
            $resized_file = $editor->save($destfilename, $mime_type);
        }

        //return the output
        if($single) {
            $image = $img_url;
        } else {
            //array return
            $image = array (
                0 => $img_url,
                1 => isset($dst_w) ? $dst_w : $orig_w,
                2 => isset($dst_h) ? $dst_h : $orig_h,
            );
        }

        return $image;
    }

    /** Shortens a number into a base 36 string
     *
     * @param $number string a string of numbers to convert
     * @param $fromBase starting base
     * @param $toBase base to convert the number to
     * @return string base converted characters
     */
    protected static function base_convert_arbitrary($number, $fromBase, $toBase) {
        $digits = '0123456789abcdefghijklmnopqrstuvwxyz';
        $length = strlen($number);
        $result = '';

        $nibbles = array();
        for ($i = 0; $i < $length; ++$i) {
            $nibbles[$i] = strpos($digits, $number[$i]);
        }

        do {
            $value = 0;
            $newlen = 0;
            for ($i = 0; $i < $length; ++$i) {
                $value = $value * $fromBase + $nibbles[$i];
                if ($value >= $toBase) {
                    $nibbles[$newlen++] = (int)($value / $toBase);
                    $value %= $toBase;
                }
                else if ($newlen > 0) {
                    $nibbles[$newlen++] = 0;
                }
            }
            $length = $newlen;
            $result = $digits[$value].$result;
        }
        while ($newlen != 0);
        return $result;
    }
}
}


// don't use the default resizer since we want to allow resizing to larger sizes (than the original one)
// Parts are copied from media.php
// Crop is always applied (just like timthumb)
add_filter('image_resize_dimensions', 'bfi_image_resize_dimensions', 10, 5);
if ( !function_exists( 'bfi_image_resize_dimensions' ) ) {
function bfi_image_resize_dimensions($payload, $orig_w, $orig_h, $dest_w, $dest_h, $crop = false) {
    $aspect_ratio = $orig_w / $orig_h;

    $new_w = $dest_w;
    $new_h = $dest_h;

    if ( !$new_w ) {
        $new_w = intval($new_h * $aspect_ratio);
    }

    if ( !$new_h ) {
        $new_h = intval($new_w / $aspect_ratio);
    }

    $size_ratio = max($new_w / $orig_w, $new_h / $orig_h);

    $crop_w = round($new_w / $size_ratio);
    $crop_h = round($new_h / $size_ratio);
    $s_x = floor( ($orig_w - $crop_w) / 2 );
    $s_y = floor( ($orig_h - $crop_h) / 2 );

    // the return array matches the parameters to imagecopyresampled()
    // int dst_x, int dst_y, int src_x, int src_y, int dst_w, int dst_h, int src_w, int src_h
    return array( 0, 0, (int) $s_x, (int) $s_y, (int) $new_w, (int) $new_h, (int) $crop_w, (int) $crop_h );
}
}


// This function allows us to latch on WP image functions such as
// the_post_thumbnail, get_image_tag and wp_get_attachment_image_src
// so that you won't have to use the function bfi_thumb in order to do resizing.
// To make this work, in the WP image functions, when specifying an
// array for the image dimensions, add a 'bfi_thumb' => true to
// the array, then add your normal $params arguments.
//
// e.g. the_post_thumbnail( array( 1024, 400, 'bfi_thumb' => true, 'grayscale' => true ) );
add_filter( 'image_downsize', 'bfi_image_downsize', 1, 3 );
if ( !function_exists( 'bfi_image_downsize' ) ) {
function bfi_image_downsize( $out, $id, $size ) {
    if ( ! is_array( $size ) ) {
        return false;
    }
    if ( ! array_key_exists( 'bfi_thumb', $size ) ) {
        return false;
    }
    if ( empty( $size['bfi_thumb'] ) ) {
        return false;
    }

    $img_url = wp_get_attachment_url( $id );

    $params = $size;
    $params['width'] = $size[0];
    $params['height'] = $size[1];

    $resized_img_url = bfi_thumb( $img_url, $params );

    return array( $resized_img_url, $size[0], $size[1], false );
}
}