Kohana_Image.php 29.1 KB
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<?php
namespace common\components\artboximage\drivers\Kohana;

use common\components\artboximage\drivers\Image;
use yii\base\ErrorException;
/**
 * Image manipulation support. Allows images to be resized, cropped, etc.
 *
 * @package    Kohana/Image
 * @category   Base
 * @author     Kohana Team
 * @copyright  (c) 2008-2009 Kohana Team
 * @license    http://kohanaphp.com/license.html
 */
abstract class Kohana_Image {

        // Resizing constraints
        const NONE    = 0x01;
        const WIDTH   = 0x02;
        const HEIGHT  = 0x03;
        const AUTO    = 0x04;
        const INVERSE = 0x05;
        const PRECISE = 0x06;
        const ADAPT   = 0x07;
        const CROP    = 0x08;

        // Flipping directions
        const HORIZONTAL = 0x11;
        const VERTICAL   = 0x12;

        /**
         * @var  string  default driver: GD, ImageMagick, etc
         */
        public static $default_driver = 'GD';

        // Status of the driver check
        protected static $_checked = FALSE;

        /**
         * Loads an image and prepares it for manipulation.
         *
         *     $image = Image::factory('upload/test.jpg');
         *
         * @param   string   $file    image file path
         * @param   string   $driver  driver type: GD, ImageMagick, etc
         * @return  Image
         * @uses    Image::$default_driver
         */
        public static function factory($file, $driver = NULL)
        {
                if ($driver === NULL)
                {
                       
                        // Use the default driver
                        $driver = Image::$default_driver;
                }

                // Set the class name
                $class = 'Image_'.$driver;

                return new Image\Image_GD(); // $class($file);
        }

        /**
         * @var  string  image file path
         */
        public $file;

        /**
         * @var  integer  image width
         */
        public $width;

        /**
         * @var  integer  image height
         */
        public $height;

        /**
         * @var  integer  one of the IMAGETYPE_* constants
         */
        public $type;

        /**
         * @var  string  mime type of the image
         */
        public $mime;

        /**
         * Loads information about the image. Will throw an exception if the image
         * does not exist or is not an image.
         *
         * @param   string  $file  image file path
         * @return  void
         * @throws  ErrorException
         */
        public function __construct($file)
        {
                try
                {
                        // Get the real path to the file
                        $file = realpath($file);

                        // Get the image information
                        $info = getimagesize($file);
                }
                catch (Exception $e)
                {
                        // Ignore all errors while reading the image
                }

                if (empty($file) OR empty($info))
                {
                        throw new ErrorException(sprintf('Not an image or invalid image: %s',$file));
                }

                // Store the image information
                $this->file   = $file;
                $this->width  = $info[0];
                $this->height = $info[1];
                $this->type   = $info[2];
                $this->mime   = image_type_to_mime_type($this->type);
        }

        /**
         * Render the current image.
         *
         *     echo $image;
         *
         * [!!] The output of this function is binary and must be rendered with the
         * appropriate Content-Type header or it will not be displayed correctly!
         *
         * @return  string
         */
        public function __toString()
        {
                try
                {
                        // Render the current image
                        return $this->render();
                }
                catch (ErrorException $e)
                {
                        /*
                        if (is_object(Kohana::$log))
                        {
                                // Get the text of the exception
                                $error = ErrorException::text($e);

                                // Add this exception to the log
                                Yii::error($error);
                        }
                        */

                        // Showing any kind of error will be "inside" image data
                        return '';
                }
        }

        /**
         * Resize the image to the given size. Either the width or the height can
         * be omitted and the image will be resized proportionally.
         *
         *     // Resize to 200 pixels on the shortest side
         *     $image->resize(200, 200);
         *
         *     // Resize to 200x200 pixels, keeping aspect ratio
         *     $image->resize(200, 200, Image::INVERSE);
         *
         *     // Resize to 500 pixel width, keeping aspect ratio
         *     $image->resize(500, NULL);
         *
         *     // Resize to 500 pixel height, keeping aspect ratio
         *     $image->resize(NULL, 500);
         *
         *     // Resize to 200x500 pixels, ignoring aspect ratio
         *     $image->resize(200, 500, Image::NONE);
         * 
         *     // Resize to 400 pixels on the shortest side, puts it in the center 
         *     // of the image with the transparent edges, keeping aspect ratio, 
         *     // output size will be 400x400 pixels
         *     $image->resize(400, 400, Image::ADAPT);
         *
         * @param   integer  $width   new width
         * @param   integer  $height  new height
         * @param   integer  $master  master dimension
         * @return  $this
         * @uses    Image::_do_resize
         */
        public function resize($width = NULL, $height = NULL, $master = NULL)
        {
                if ($master === NULL)
                {
                        // Choose the master dimension automatically
                        $master = Image::AUTO;
                }
                elseif ($master === Image::CROP)
                {
                        if (empty($width) || empty($height))
                        {
                                return $this->resize($width, $height, Image::AUTO);
                        }

                        $master = $this->width / $this->height > $width / $height ? Image::HEIGHT : Image::WIDTH;
                        $this->resize($width, $height, $master);

                        if ($this->width !== $width || $this->height !== $height) 
                        {
                                $offset_x = round(($this->width - $width) / 2);
                                $offset_y = round(($this->height - $height) / 2);
                                $this->crop($width, $height, $offset_x, $offset_y);
                        }

                        return $this;
                }
                // Image::WIDTH and Image::HEIGHT deprecated. You can use it in old projects,
                // but in new you must pass empty value for non-master dimension
                elseif ($master == Image::WIDTH AND ! empty($width))
                {
                        $master = Image::AUTO;

                        // Set empty height for backward compatibility
                        $height = NULL;
                }
                elseif ($master == Image::HEIGHT AND ! empty($height))
                {
                        $master = Image::AUTO;

                        // Set empty width for backward compatibility
                        $width = NULL;
                }
                elseif ($master === Image::ADAPT) 
                {
                        if (empty($width)) 
                        {
                                $width = $this->width * $height / $this->height;
                        } 
                        elseif (empty($height)) 
                        {
                                $height = $this->height * $width / $this->width;
                        }
                }

                if (empty($width))
                {
                        if ($master === Image::NONE)
                        {
                                // Use the current width
                                $width = $this->width;
                        }
                        else
                        {
                                // If width not set, master will be height
                                $master = Image::HEIGHT;
                        }
                }

                if (empty($height))
                {
                        if ($master === Image::NONE)
                        {
                                // Use the current height
                                $height = $this->height;
                        }
                        else
                        {
                                // If height not set, master will be width
                                $master = Image::WIDTH;
                        }
                }

                switch ($master)
                {
                        case Image::AUTO:
                                // Choose direction with the greatest reduction ratio
                                $master = ($this->width / $width) > ($this->height / $height) ? Image::WIDTH : Image::HEIGHT;
                        break;
                        case Image::INVERSE:
                                // Choose direction with the minimum reduction ratio
                                $master = ($this->width / $width) > ($this->height / $height) ? Image::HEIGHT : Image::WIDTH;
                        break;
                }

                switch ($master)
                {
                        case Image::WIDTH:
                                // Recalculate the height based on the width proportions
                                $height = $this->height * $width / $this->width;
                        break;
                        case Image::HEIGHT:
                                // Recalculate the width based on the height proportions
                                $width = $this->width * $height / $this->height;
                        break;
                        case Image::PRECISE:
                                // Resize to precise size
                                $ratio = $this->width / $this->height;

                                if ($width / $height > $ratio)
                                {
                                        $height = $this->height * $width / $this->width;
                                }
                                else
                                {
                                        $width = $this->width * $height / $this->height;
                                }
                        break;
                }

                // Convert the width and height to integers, minimum value is 1px
                $width  = max(round($width), 1);
                $height = max(round($height), 1);

                // Adapt the image if the ratios are not equivalent
                if ($master === Image::ADAPT && $width / $height !== $this->width / $this->height)
                {
                        $image_width = $bg_width = $this->width;
                        $image_height = $bg_height = $this->height;

                        $offset_x = $offset_y = 0;

                        if ($width / $height > $image_width / $image_height) 
                        {
                                $bg_width = floor($image_height * $width / $height);
                                $offset_x = abs(floor(($bg_width - $image_width) / 2));
                        }
                        else 
                        {
                                $bg_height = floor($image_width * $height / $width);
                                $offset_y = abs(floor(($bg_height - $image_height) / 2));
                        }

                        $this->_do_adapt($image_width, $image_height, $bg_width, $bg_height, $offset_x, $offset_y);
                }

                $this->_do_resize($width, $height);

                return $this;
        }

        /**
         * Crop an image to the given size. Either the width or the height can be
         * omitted and the current width or height will be used.
         *
         * If no offset is specified, the center of the axis will be used.
         * If an offset of TRUE is specified, the bottom of the axis will be used.
         *
         *     // Crop the image to 200x200 pixels, from the center
         *     $image->crop(200, 200);
         *
         * @param   integer  $width     new width
         * @param   integer  $height    new height
         * @param   mixed    $offset_x  offset from the left
         * @param   mixed    $offset_y  offset from the top
         * @return  $this
         * @uses    Image::_do_crop
         */
        public function crop($width, $height, $offset_x = NULL, $offset_y = NULL)
        {
                if ($width > $this->width)
                {
                        // Use the current width
                        $width = $this->width;
                }

                if ($height > $this->height)
                {
                        // Use the current height
                        $height = $this->height;
                }

                if ($offset_x === NULL)
                {
                        // Center the X offset
                        $offset_x = round(($this->width - $width) / 2);
                }
                elseif ($offset_x === TRUE)
                {
                        // Bottom the X offset
                        $offset_x = $this->width - $width;
                }
                elseif ($offset_x < 0)
                {
                        // Set the X offset from the right
                        $offset_x = $this->width - $width + $offset_x;
                }

                if ($offset_y === NULL)
                {
                        // Center the Y offset
                        $offset_y = round(($this->height - $height) / 2);
                }
                elseif ($offset_y === TRUE)
                {
                        // Bottom the Y offset
                        $offset_y = $this->height - $height;
                }
                elseif ($offset_y < 0)
                {
                        // Set the Y offset from the bottom
                        $offset_y = $this->height - $height + $offset_y;
                }

                // Determine the maximum possible width and height
                $max_width  = $this->width  - $offset_x;
                $max_height = $this->height - $offset_y;

                if ($width > $max_width)
                {
                        // Use the maximum available width
                        $width = $max_width;
                }

                if ($height > $max_height)
                {
                        // Use the maximum available height
                        $height = $max_height;
                }

                $this->_do_crop($width, $height, $offset_x, $offset_y);

                return $this;
        }

        /**
         * Rotate the image by a given amount.
         *
         *     // Rotate 45 degrees clockwise
         *     $image->rotate(45);
         *
         *     // Rotate 90% counter-clockwise
         *     $image->rotate(-90);
         *
         * @param   integer  $degrees  degrees to rotate: -360-360
         * @return  $this
         * @uses    Image::_do_rotate
         */
        public function rotate($degrees)
        {
                // Make the degrees an integer
                $degrees = (int) $degrees;

                if ($degrees > 180)
                {
                        do
                        {
                                // Keep subtracting full circles until the degrees have normalized
                                $degrees -= 360;
                        }
                        while ($degrees > 180);
                }

                if ($degrees < -180)
                {
                        do
                        {
                                // Keep adding full circles until the degrees have normalized
                                $degrees += 360;
                        }
                        while ($degrees < -180);
                }

                $this->_do_rotate($degrees);

                return $this;
        }

        /**
         * Flip the image along the horizontal or vertical axis.
         *
         *     // Flip the image from top to bottom
         *     $image->flip(Image::HORIZONTAL);
         *
         *     // Flip the image from left to right
         *     $image->flip(Image::VERTICAL);
         *
         * @param   integer  $direction  direction: Image::HORIZONTAL, Image::VERTICAL
         * @return  $this
         * @uses    Image::_do_flip
         */
        public function flip($direction)
        {
                if ($direction !== Image::HORIZONTAL)
                {
                        // Flip vertically
                        $direction = Image::VERTICAL;
                }

                $this->_do_flip($direction);

                return $this;
        }

        /**
         * Sharpen the image by a given amount.
         *
         *     // Sharpen the image by 20%
         *     $image->sharpen(20);
         *
         * @param   integer  $amount  amount to sharpen: 1-100
         * @return  $this
         * @uses    Image::_do_sharpen
         */
        public function sharpen($amount)
        {
                // The amount must be in the range of 1 to 100
                $amount = min(max($amount, 1), 100);

                $this->_do_sharpen($amount);

                return $this;
        }

        /**
         * Add a reflection to an image. The most opaque part of the reflection
         * will be equal to the opacity setting and fade out to full transparent.
         * Alpha transparency is preserved.
         *
         *     // Create a 50 pixel reflection that fades from 0-100% opacity
         *     $image->reflection(50);
         *
         *     // Create a 50 pixel reflection that fades from 100-0% opacity
         *     $image->reflection(50, 100, TRUE);
         *
         *     // Create a 50 pixel reflection that fades from 0-60% opacity
         *     $image->reflection(50, 60, TRUE);
         *
         * [!!] By default, the reflection will be go from transparent at the top
         * to opaque at the bottom.
         *
         * @param   integer   $height   reflection height
         * @param   integer   $opacity  reflection opacity: 0-100
         * @param   boolean   $fade_in  TRUE to fade in, FALSE to fade out
         * @return  $this
         * @uses    Image::_do_reflection
         */
        public function reflection($height = NULL, $opacity = 100, $fade_in = FALSE)
        {
                if ($height === NULL OR $height > $this->height)
                {
                        // Use the current height
                        $height = $this->height;
                }

                // The opacity must be in the range of 0 to 100
                $opacity = min(max($opacity, 0), 100);

                $this->_do_reflection($height, $opacity, $fade_in);

                return $this;
        }

        /**
         * Add a watermark to an image with a specified opacity. Alpha transparency
         * will be preserved.
         *
         * If no offset is specified, the center of the axis will be used.
         * If an offset of TRUE is specified, the bottom of the axis will be used.
         *
         *     // Add a watermark to the bottom right of the image
         *     $mark = Image::factory('upload/watermark.png');
         *     $image->watermark($mark, TRUE, TRUE);
         *
         * @param   Kohana_Image  $watermark  watermark Image instance
         * @param   integer       $offset_x   offset from the left
         * @param   integer       $offset_y   offset from the top
         * @param   integer       $opacity    opacity of watermark: 1-100
         * @return  $this
         * @uses    Image::_do_watermark
         */
        public function watermark(Kohana_Image $watermark, $offset_x = NULL, $offset_y = NULL, $opacity = 100)
        {
                if ($offset_x === NULL)
                {
                        // Center the X offset
                        $offset_x = round(($this->width - $watermark->width) / 2);
                }
                elseif ($offset_x === TRUE)
                {
                        // Bottom the X offset
                        $offset_x = $this->width - $watermark->width;
                }
                elseif ($offset_x < 0)
                {
                        // Set the X offset from the right
                        $offset_x = $this->width - $watermark->width + $offset_x;
                }

                if ($offset_y === NULL)
                {
                        // Center the Y offset
                        $offset_y = round(($this->height - $watermark->height) / 2);
                }
                elseif ($offset_y === TRUE)
                {
                        // Bottom the Y offset
                        $offset_y = $this->height - $watermark->height;
                }
                elseif ($offset_y < 0)
                {
                        // Set the Y offset from the bottom
                        $offset_y = $this->height - $watermark->height + $offset_y;
                }

                // The opacity must be in the range of 1 to 100
                $opacity = min(max($opacity, 1), 100);

                $this->_do_watermark($watermark, $offset_x, $offset_y, $opacity);

                return $this;
        }

        /**
         * Set the background color of an image. This is only useful for images
         * with alpha transparency.
         *
         *     // Make the image background black
         *     $image->background('#000');
         *
         *     // Make the image background black with 50% opacity
         *     $image->background('#000', 50);
         *
         * @param   string   $color    hexadecimal color value
         * @param   integer  $opacity  background opacity: 0-100
         * @return  $this
         * @uses    Image::_do_background
         */
        public function background($color, $opacity = 100)
        {
                if ($color[0] === '#')
                {
                        // Remove the pound
                        $color = substr($color, 1);
                }

                if (strlen($color) === 3)
                {
                        // Convert shorthand into longhand hex notation
                        $color = preg_replace('/./', '$0$0', $color);
                }

                // Convert the hex into RGB values
                list ($r, $g, $b) = array_map('hexdec', str_split($color, 2));

                // The opacity must be in the range of 0 to 100
                $opacity = min(max($opacity, 0), 100);

                $this->_do_background($r, $g, $b, $opacity);

                return $this;
        }

        /**
         * Save the image. If the filename is omitted, the original image will
         * be overwritten.
         *
         *     // Save the image as a PNG
         *     $image->save('saved/cool.png');
         *
         *     // Overwrite the original image
         *     $image->save();
         *
         * [!!] If the file exists, but is not writable, an exception will be thrown.
         *
         * [!!] If the file does not exist, and the directory is not writable, an
         * exception will be thrown.
         *
         * @param   string   $file     new image path
         * @param   integer  $quality  quality of image: 1-100
         * @return  boolean
         * @uses    Image::_save
         * @throws  ErrorException
         */
        public function save($file = NULL, $quality = 100)
        {
                if ($file === NULL)
                {
                        // Overwrite the file
                        $file = $this->file;
                }

                if (is_file($file))
                {
                        if ( ! is_writable($file))
                        {
                                throw new ErrorException(sprintf('File must be writable: %s',$file));
                        }
                }
                else
                {
                        // Get the directory of the file
                        $directory = realpath(pathinfo($file, PATHINFO_DIRNAME));

                        if ( ! is_dir($directory) OR ! is_writable($directory))
                        {
                                throw new ErrorException(sprintf('Directory must be writable: %s',$directory));
                        }
                }

                // The quality must be in the range of 1 to 100
                $quality = min(max($quality, 1), 100);

                return $this->_do_save($file, $quality);
        }

        /**
         * Render the image and return the binary string.
         *
         *     // Render the image at 50% quality
         *     $data = $image->render(NULL, 50);
         *
         *     // Render the image as a PNG
         *     $data = $image->render('png');
         *
         * @param   string   $type     image type to return: png, jpg, gif, etc
         * @param   integer  $quality  quality of image: 1-100
         * @return  string
         * @uses    Image::_do_render
         */
        public function render($type = NULL, $quality = 100)
        {
                if ($type === NULL)
                {
                        // Use the current image type
                        $type = image_type_to_extension($this->type, FALSE);
                }

                return $this->_do_render($type, $quality);
        }

        /**
         * Execute a resize.
         *
         * @param   integer  $width   new width
         * @param   integer  $height  new height
         * @return  void
         */
        abstract protected function _do_resize($width, $height);

        /**
         * Adaptation the image.
         * 
         * @param   integer  $width      image width
         * @param   integer  $height     image height
         * @param   integer  $bg_width   background width
         * @param   integer  $bg_height  background height
         * @param   integer  $offset_x   offset from the left
         * @param   integer  $offset_y   offset from the top
         */
        abstract protected function _do_adapt($width, $height, $bg_width, $bg_height, $offset_x, $offset_y);

        /**
         * Execute a crop.
         *
         * @param   integer  $width     new width
         * @param   integer  $height    new height
         * @param   integer  $offset_x  offset from the left
         * @param   integer  $offset_y  offset from the top
         * @return  void
         */
        abstract protected function _do_crop($width, $height, $offset_x, $offset_y);

        /**
         * Execute a rotation.
         *
         * @param   integer  $degrees  degrees to rotate
         * @return  void
         */
        abstract protected function _do_rotate($degrees);

        /**
         * Execute a flip.
         *
         * @param   integer  $direction  direction to flip
         * @return  void
         */
        abstract protected function _do_flip($direction);

        /**
         * Execute a sharpen.
         *
         * @param   integer  $amount  amount to sharpen
         * @return  void
         */
        abstract protected function _do_sharpen($amount);

        /**
         * Execute a reflection.
         *
         * @param   integer   $height   reflection height
         * @param   integer   $opacity  reflection opacity
         * @param   boolean   $fade_in  TRUE to fade out, FALSE to fade in
         * @return  void
         */
        abstract protected function _do_reflection($height, $opacity, $fade_in);

        /**
         * Execute a watermarking.
         *
         * @param   Kohana_Image  $image     watermarking Kohana_Image
         * @param   integer       $offset_x  offset from the left
         * @param   integer       $offset_y  offset from the top
         * @param   integer       $opacity   opacity of watermark
         * @return  void
         */
        abstract protected function _do_watermark(Kohana_Image $image, $offset_x, $offset_y, $opacity);

        /**
         * Execute a background.
         *
         * @param   integer  $r        red
         * @param   integer  $g        green
         * @param   integer  $b        blue
         * @param   integer  $opacity  opacity
         * @return void
         */
        abstract protected function _do_background($r, $g, $b, $opacity);

        /**
         * Execute a save.
         *
         * @param   string   $file     new image filename
         * @param   integer  $quality  quality
         * @return  boolean
         */
        abstract protected function _do_save($file, $quality);

        /**
         * Execute a render.
         *
         * @param   string    $type     image type: png, jpg, gif, etc
         * @param   integer   $quality  quality
         * @return  string
         */
        abstract protected function _do_render($type, $quality);

} // End Image