Modules

Kohana_Image_GD
extends Image
extends Kohana_Image

This class is a transparent base class for Image_GD and should not be accessed directly.

Support for image manipulation using GD.

package
Kohana/Image
category
Drivers
author
Kohana Team
copyright
© 2008-2009 Kohana Team
license
http://kohanaphp.com/license.html

Class declared in MODPATH/image/classes/Kohana/Image/GD.php on line 11.

Constants

IMAGEROTATE

string(11) "imagerotate"

IMAGECONVOLUTION

string(16) "imageconvolution"

IMAGEFILTER

string(11) "imagefilter"

IMAGELAYEREFFECT

string(16) "imagelayereffect"

NONE

integer 1

WIDTH

integer 2

HEIGHT

integer 3

AUTO

integer 4

INVERSE

integer 5

PRECISE

integer 6

HORIZONTAL

integer 17

VERTICAL

integer 18

Properties

public static string $default_driver

default driver: GD, ImageMagick, etc

string(2) "GD"

public string $file

image file path

Default value:
NULL

public integer $height

image height

Default value:
NULL

public string $mime

mime type of the image

Default value:
NULL

public integer $type

one of the IMAGETYPE_* constants

Default value:
NULL

public integer $width

image width

Default value:
NULL

protected static $_available_functions

array(0) 

protected static $_checked

bool FALSE

protected $_create_function

Default value:
NULL

protected $_image

Default value:
NULL

Methods

public __construct( string $file ) (defined in Kohana_Image_GD)

Runs Image_GD::check and loads the image.

Parameters

  • string $file required - Image file path

Tags

Return Values

  • void

Source Code

public function __construct($file)
{
	if ( ! Image_GD::$_checked)
	{
		// Run the install check
		Image_GD::check();
	}

	parent::__construct($file);

	// Set the image creation function name
	switch ($this->type)
	{
		case IMAGETYPE_JPEG:
			$create = 'imagecreatefromjpeg';
		break;
		case IMAGETYPE_GIF:
			$create = 'imagecreatefromgif';
		break;
		case IMAGETYPE_PNG:
			$create = 'imagecreatefrompng';
		break;
	}

	if ( ! isset($create) OR ! function_exists($create))
	{
		throw new Kohana_Exception('Installed GD does not support :type images',
			array(':type' => image_type_to_extension($this->type, FALSE)));
	}

	// Save function for future use
	$this->_create_function = $create;

	// Save filename for lazy loading
	$this->_image = $this->file;
}

public __destruct( ) (defined in Kohana_Image_GD)

Destroys the loaded image to free up resources.

Return Values

  • void

Source Code

public function __destruct()
{
	if (is_resource($this->_image))
	{
		// Free all resources
		imagedestroy($this->_image);
	}
}

public static check( ) (defined in Kohana_Image_GD)

Checks if GD is enabled and verify that key methods exist, some of which require GD to be bundled with PHP. Exceptions will be thrown from those methods when GD is not bundled.

Return Values

  • boolean

Source Code

public static function check()
{
	if ( ! function_exists('gd_info'))
	{
		throw new Kohana_Exception('GD is either not installed or not enabled, check your configuration');
	}
	$functions = array(
		Image_GD::IMAGEROTATE,
		Image_GD::IMAGECONVOLUTION,
		Image_GD::IMAGEFILTER,
		Image_GD::IMAGELAYEREFFECT
	);
	foreach ($functions as $function)
	{
		Image_GD::$_available_functions[$function] = function_exists($function);
	}

	if (defined('GD_VERSION'))
	{
		// Get the version via a constant, available in PHP 5.2.4+
		$version = GD_VERSION;
	}
	else
	{
		// Get the version information
		$info = gd_info();

		// Extract the version number
		preg_match('/\d+\.\d+(?:\.\d+)?/', $info['GD Version'], $matches);

		// Get the major version
		$version = $matches[0];
	}

	if ( ! version_compare($version, '2.0.1', '>='))
	{
		throw new Kohana_Exception('Image_GD requires GD version :required or greater, you have :version',
			array('required' => '2.0.1', ':version' => $version));
	}

	return Image_GD::$_checked = TRUE;
}

public __toString( ) (defined in Kohana_Image)

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 Values

  • string

Source Code

public function __toString()
{
	try
	{
		// Render the current image
		return $this->render();
	}
	catch (Exception $e)
	{
		if (is_object(Kohana::$log))
		{
			// Get the text of the exception
			$error = Kohana_Exception::text($e);

			// Add this exception to the log
			Kohana::$log->add(Log::ERROR, $error);
		}

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

public background( string $color [, integer $opacity = integer 100 ] ) (defined in Kohana_Image)

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);

Parameters

  • string $color required - Hexadecimal color value
  • integer $opacity = integer 100 - Background opacity: 0-100

Tags

Return Values

  • $this

Source Code

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;
}

public crop( integer $width , integer $height [, mixed $offset_x = NULL , mixed $offset_y = NULL ] ) (defined in Kohana_Image)

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);

Parameters

  • integer $width required - New width
  • integer $height required - New height
  • mixed $offset_x = NULL - Offset from the left
  • mixed $offset_y = NULL - Offset from the top

Tags

Return Values

  • $this

Source Code

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;
}

public static factory( string $file [, string $driver = NULL ] ) (defined in Kohana_Image)

Loads an image and prepares it for manipulation.

$image = Image::factory('upload/test.jpg');

Parameters

  • string $file required - Image file path
  • string $driver = NULL - Driver type: GD, ImageMagick, etc

Tags

Return Values

  • Image

Source Code

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 $class($file);
}

public flip( integer $direction ) (defined in Kohana_Image)

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);

Parameters

  • integer $direction required - Direction: Image::HORIZONTAL, Image::VERTICAL

Tags

Return Values

  • $this

Source Code

public function flip($direction)
{
	if ($direction !== Image::HORIZONTAL)
	{
		// Flip vertically
		$direction = Image::VERTICAL;
	}

	$this->_do_flip($direction);

	return $this;
}

public reflection( [ integer $height = NULL , integer $opacity = integer 100 , boolean $fade_in = bool FALSE ] ) (defined in Kohana_Image)

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.

Parameters

  • integer $height = NULL - Reflection height
  • integer $opacity = integer 100 - Reflection opacity: 0-100
  • boolean $fade_in = bool FALSE - TRUE to fade in, FALSE to fade out

Tags

Return Values

  • $this

Source Code

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;
}

public render( [ string $type = NULL , integer $quality = integer 100 ] ) (defined in Kohana_Image)

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');

Parameters

  • string $type = NULL - Image type to return: png, jpg, gif, etc
  • integer $quality = integer 100 - Quality of image: 1-100

Tags

Return Values

  • string

Source Code

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);
}

public resize( [ integer $width = NULL , integer $height = NULL , integer $master = NULL ] ) (defined in Kohana_Image)

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);

Parameters

  • integer $width = NULL - New width
  • integer $height = NULL - New height
  • integer $master = NULL - Master dimension

Tags

Return Values

  • $this

Source Code

public function resize($width = NULL, $height = NULL, $master = NULL)
{
	if ($master === NULL)
	{
		// Choose the master dimension automatically
		$master = Image::AUTO;
	}
	// Image::WIDTH and Image::HEIGHT deprecated. You can use it in old projects,
	// but in new you must pass empty value for non-master dimension
	elseif ($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;
	}

	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);

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

	return $this;
}

public rotate( integer $degrees ) (defined in Kohana_Image)

Rotate the image by a given amount.

// Rotate 45 degrees clockwise
$image->rotate(45);

// Rotate 90% counter-clockwise
$image->rotate(-90);

Parameters

  • integer $degrees required - Degrees to rotate: -360-360

Tags

Return Values

  • $this

Source Code

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;
}

public save( [ string $file = NULL , integer $quality = integer 100 ] ) (defined in Kohana_Image)

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.

Parameters

  • string $file = NULL - New image path
  • integer $quality = integer 100 - Quality of image: 1-100

Tags

Return Values

  • boolean

Source Code

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 Kohana_Exception('File must be writable: :file',
				array(':file' => Debug::path($file)));
		}
	}
	else
	{
		// Get the directory of the file
		$directory = realpath(pathinfo($file, PATHINFO_DIRNAME));

		if ( ! is_dir($directory) OR ! is_writable($directory))
		{
			throw new Kohana_Exception('Directory must be writable: :directory',
				array(':directory' => Debug::path($directory)));
		}
	}

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

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

public sharpen( integer $amount ) (defined in Kohana_Image)

Sharpen the image by a given amount.

// Sharpen the image by 20%
$image->sharpen(20);

Parameters

  • integer $amount required - Amount to sharpen: 1-100

Tags

Return Values

  • $this

Source Code

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;
}

public watermark( Image $watermark [, integer $offset_x = NULL , integer $offset_y = NULL , integer $opacity = integer 100 ] ) (defined in Kohana_Image)

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);

Parameters

  • Image $watermark required - Watermark Image instance
  • integer $offset_x = NULL - Offset from the left
  • integer $offset_y = NULL - Offset from the top
  • integer $opacity = integer 100 - Opacity of watermark: 1-100

Tags

Return Values

  • $this

Source Code

public function watermark(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;
}

protected _create( integer $width , integer $height ) (defined in Kohana_Image_GD)

Create an empty image with the given width and height.

Parameters

  • integer $width required - Image width
  • integer $height required - Image height

Return Values

  • resource

Source Code

protected function _create($width, $height)
{
	// Create an empty image
	$image = imagecreatetruecolor($width, $height);

	// Do not apply alpha blending
	imagealphablending($image, FALSE);

	// Save alpha levels
	imagesavealpha($image, TRUE);

	return $image;
}

protected _do_background( integer $r , integer $g , integer $b , integer $opacity ) (defined in Kohana_Image_GD)

Execute a background.

Parameters

  • integer $r required - Red
  • integer $g required - Green
  • integer $b required - Blue
  • integer $opacity required - Opacity

Return Values

  • void

Source Code

protected function _do_background($r, $g, $b, $opacity)
{
	// Loads image if not yet loaded
	$this->_load_image();

	// Convert an opacity range of 0-100 to 127-0
	$opacity = round(abs(($opacity * 127 / 100) - 127));

	// Create a new background
	$background = $this->_create($this->width, $this->height);

	// Allocate the color
	$color = imagecolorallocatealpha($background, $r, $g, $b, $opacity);

	// Fill the image with white
	imagefilledrectangle($background, 0, 0, $this->width, $this->height, $color);

	// Alpha blending must be enabled on the background!
	imagealphablending($background, TRUE);

	// Copy the image onto a white background to remove all transparency
	if (imagecopy($background, $this->_image, 0, 0, 0, 0, $this->width, $this->height))
	{
		// Swap the new image for the old one
		imagedestroy($this->_image);
		$this->_image = $background;
	}
}

protected _do_crop( integer $width , integer $height , integer $offset_x , integer $offset_y ) (defined in Kohana_Image_GD)

Execute a crop.

Parameters

  • integer $width required - New width
  • integer $height required - New height
  • integer $offset_x required - Offset from the left
  • integer $offset_y required - Offset from the top

Return Values

  • void

Source Code

protected function _do_crop($width, $height, $offset_x, $offset_y)
{
	// Create the temporary image to copy to
	$image = $this->_create($width, $height);

	// Loads image if not yet loaded
	$this->_load_image();

	// Execute the crop
	if (imagecopyresampled($image, $this->_image, 0, 0, $offset_x, $offset_y, $width, $height, $width, $height))
	{
		// Swap the new image for the old one
		imagedestroy($this->_image);
		$this->_image = $image;

		// Reset the width and height
		$this->width  = imagesx($image);
		$this->height = imagesy($image);
	}
}

protected _do_flip( integer $direction ) (defined in Kohana_Image_GD)

Execute a flip.

Parameters

  • integer $direction required - Direction to flip

Return Values

  • void

Source Code

protected function _do_flip($direction)
{
	// Create the flipped image
	$flipped = $this->_create($this->width, $this->height);

	// Loads image if not yet loaded
	$this->_load_image();

	if ($direction === Image::HORIZONTAL)
	{
		for ($x = 0; $x < $this->width; $x++)
		{
			// Flip each row from top to bottom
			imagecopy($flipped, $this->_image, $x, 0, $this->width - $x - 1, 0, 1, $this->height);
		}
	}
	else
	{
		for ($y = 0; $y < $this->height; $y++)
		{
			// Flip each column from left to right
			imagecopy($flipped, $this->_image, 0, $y, 0, $this->height - $y - 1, $this->width, 1);
		}
	}

	// Swap the new image for the old one
	imagedestroy($this->_image);
	$this->_image = $flipped;

	// Reset the width and height
	$this->width  = imagesx($flipped);
	$this->height = imagesy($flipped);
}

protected _do_reflection( integer $height , integer $opacity , boolean $fade_in ) (defined in Kohana_Image_GD)

Execute a reflection.

Parameters

  • integer $height required - Reflection height
  • integer $opacity required - Reflection opacity
  • boolean $fade_in required - TRUE to fade out, FALSE to fade in

Return Values

  • void

Source Code

protected function _do_reflection($height, $opacity, $fade_in)
{
	if (empty(Image_GD::$_available_functions[Image_GD::IMAGEFILTER]))
	{
		throw new Kohana_Exception('This method requires :function, which is only available in the bundled version of GD',
			array(':function' => 'imagefilter'));
	}

	// Loads image if not yet loaded
	$this->_load_image();

	// Convert an opacity range of 0-100 to 127-0
	$opacity = round(abs(($opacity * 127 / 100) - 127));

	if ($opacity < 127)
	{
		// Calculate the opacity stepping
		$stepping = (127 - $opacity) / $height;
	}
	else
	{
		// Avoid a "divide by zero" error
		$stepping = 127 / $height;
	}

	// Create the reflection image
	$reflection = $this->_create($this->width, $this->height + $height);

	// Copy the image to the reflection
	imagecopy($reflection, $this->_image, 0, 0, 0, 0, $this->width, $this->height);

	for ($offset = 0; $height >= $offset; $offset++)
	{
		// Read the next line down
		$src_y = $this->height - $offset - 1;

		// Place the line at the bottom of the reflection
		$dst_y = $this->height + $offset;

		if ($fade_in === TRUE)
		{
			// Start with the most transparent line first
			$dst_opacity = round($opacity + ($stepping * ($height - $offset)));
		}
		else
		{
			// Start with the most opaque line first
			$dst_opacity = round($opacity + ($stepping * $offset));
		}

		// Create a single line of the image
		$line = $this->_create($this->width, 1);

		// Copy a single line from the current image into the line
		imagecopy($line, $this->_image, 0, 0, 0, $src_y, $this->width, 1);

		// Colorize the line to add the correct alpha level
		imagefilter($line, IMG_FILTER_COLORIZE, 0, 0, 0, $dst_opacity);

		// Copy a the line into the reflection
		imagecopy($reflection, $line, 0, $dst_y, 0, 0, $this->width, 1);
	}

	// Swap the new image for the old one
	imagedestroy($this->_image);
	$this->_image = $reflection;

	// Reset the width and height
	$this->width  = imagesx($reflection);
	$this->height = imagesy($reflection);
}

protected _do_render( string $type , integer $quality ) (defined in Kohana_Image_GD)

Execute a render.

Parameters

  • string $type required - Image type: png, jpg, gif, etc
  • integer $quality required - Quality

Return Values

  • string

Source Code

protected function _do_render($type, $quality)
{
	// Loads image if not yet loaded
	$this->_load_image();

	// Get the save function and IMAGETYPE
	list($save, $type) = $this->_save_function($type, $quality);

	// Capture the output
	ob_start();

	// Render the image
	$status = isset($quality) ? $save($this->_image, NULL, $quality) : $save($this->_image, NULL);

	if ($status === TRUE AND $type !== $this->type)
	{
		// Reset the image type and mime type
		$this->type = $type;
		$this->mime = image_type_to_mime_type($type);
	}

	return ob_get_clean();
}

protected _do_resize( integer $width , integer $height ) (defined in Kohana_Image_GD)

Execute a resize.

Parameters

  • integer $width required - New width
  • integer $height required - New height

Return Values

  • void

Source Code

protected function _do_resize($width, $height)
{
	// Presize width and height
	$pre_width = $this->width;
	$pre_height = $this->height;

	// Loads image if not yet loaded
	$this->_load_image();

	// Test if we can do a resize without resampling to speed up the final resize
	if ($width > ($this->width / 2) AND $height > ($this->height / 2))
	{
		// The maximum reduction is 10% greater than the final size
		$reduction_width  = round($width  * 1.1);
		$reduction_height = round($height * 1.1);

		while ($pre_width / 2 > $reduction_width AND $pre_height / 2 > $reduction_height)
		{
			// Reduce the size using an O(2n) algorithm, until it reaches the maximum reduction
			$pre_width /= 2;
			$pre_height /= 2;
		}

		// Create the temporary image to copy to
		$image = $this->_create($pre_width, $pre_height);

		if (imagecopyresized($image, $this->_image, 0, 0, 0, 0, $pre_width, $pre_height, $this->width, $this->height))
		{
			// Swap the new image for the old one
			imagedestroy($this->_image);
			$this->_image = $image;
		}
	}

	// Create the temporary image to copy to
	$image = $this->_create($width, $height);

	// Execute the resize
	if (imagecopyresampled($image, $this->_image, 0, 0, 0, 0, $width, $height, $pre_width, $pre_height))
	{
		// Swap the new image for the old one
		imagedestroy($this->_image);
		$this->_image = $image;

		// Reset the width and height
		$this->width  = imagesx($image);
		$this->height = imagesy($image);
	}
}

protected _do_rotate( integer $degrees ) (defined in Kohana_Image_GD)

Execute a rotation.

Parameters

  • integer $degrees required - Degrees to rotate

Return Values

  • void

Source Code

protected function _do_rotate($degrees)
{
	if (empty(Image_GD::$_available_functions[Image_GD::IMAGEROTATE]))
	{
		throw new Kohana_Exception('This method requires :function, which is only available in the bundled version of GD',
			array(':function' => 'imagerotate'));
	}

	// Loads image if not yet loaded
	$this->_load_image();

	// Transparent black will be used as the background for the uncovered region
	$transparent = imagecolorallocatealpha($this->_image, 0, 0, 0, 127);

	// Rotate, setting the transparent color
	$image = imagerotate($this->_image, 360 - $degrees, $transparent, 1);

	// Save the alpha of the rotated image
	imagesavealpha($image, TRUE);

	// Get the width and height of the rotated image
	$width  = imagesx($image);
	$height = imagesy($image);

	if (imagecopymerge($this->_image, $image, 0, 0, 0, 0, $width, $height, 100))
	{
		// Swap the new image for the old one
		imagedestroy($this->_image);
		$this->_image = $image;

		// Reset the width and height
		$this->width  = $width;
		$this->height = $height;
	}
}

protected _do_save( string $file , integer $quality ) (defined in Kohana_Image_GD)

Execute a save.

Parameters

  • string $file required - New image filename
  • integer $quality required - Quality

Return Values

  • boolean

Source Code

protected function _do_save($file, $quality)
{
	// Loads image if not yet loaded
	$this->_load_image();

	// Get the extension of the file
	$extension = pathinfo($file, PATHINFO_EXTENSION);

	// Get the save function and IMAGETYPE
	list($save, $type) = $this->_save_function($extension, $quality);

	// Save the image to a file
	$status = isset($quality) ? $save($this->_image, $file, $quality) : $save($this->_image, $file);

	if ($status === TRUE AND $type !== $this->type)
	{
		// Reset the image type and mime type
		$this->type = $type;
		$this->mime = image_type_to_mime_type($type);
	}

	return TRUE;
}

protected _do_sharpen( integer $amount ) (defined in Kohana_Image_GD)

Execute a sharpen.

Parameters

  • integer $amount required - Amount to sharpen

Return Values

  • void

Source Code

protected function _do_sharpen($amount)
{
	if (empty(Image_GD::$_available_functions[Image_GD::IMAGECONVOLUTION]))
	{
		throw new Kohana_Exception('This method requires :function, which is only available in the bundled version of GD',
			array(':function' => 'imageconvolution'));
	}

	// Loads image if not yet loaded
	$this->_load_image();

	// Amount should be in the range of 18-10
	$amount = round(abs(-18 + ($amount * 0.08)), 2);

	// Gaussian blur matrix
	$matrix = array
	(
		array(-1,   -1,    -1),
		array(-1, $amount, -1),
		array(-1,   -1,    -1),
	);

	// Perform the sharpen
	if (imageconvolution($this->_image, $matrix, $amount - 8, 0))
	{
		// Reset the width and height
		$this->width  = imagesx($this->_image);
		$this->height = imagesy($this->_image);
	}
}

protected _do_watermark( Image $watermark , integer $offset_x , integer $offset_y , integer $opacity ) (defined in Kohana_Image_GD)

Execute a watermarking.

Parameters

  • Image $watermark required - $image watermarking Image
  • integer $offset_x required - Offset from the left
  • integer $offset_y required - Offset from the top
  • integer $opacity required - Opacity of watermark

Return Values

  • void

Source Code

protected function _do_watermark(Image $watermark, $offset_x, $offset_y, $opacity)
{
	if (empty(Image_GD::$_available_functions[Image_GD::IMAGELAYEREFFECT]))
	{
		throw new Kohana_Exception('This method requires :function, which is only available in the bundled version of GD',
			array(':function' => 'imagelayereffect'));
	}

	// Loads image if not yet loaded
	$this->_load_image();

	// Create the watermark image resource
	$overlay = imagecreatefromstring($watermark->render());

	imagesavealpha($overlay, TRUE);

	// Get the width and height of the watermark
	$width  = imagesx($overlay);
	$height = imagesy($overlay);

	if ($opacity < 100)
	{
		// Convert an opacity range of 0-100 to 127-0
		$opacity = round(abs(($opacity * 127 / 100) - 127));

		// Allocate transparent gray
		$color = imagecolorallocatealpha($overlay, 127, 127, 127, $opacity);

		// The transparent image will overlay the watermark
		imagelayereffect($overlay, IMG_EFFECT_OVERLAY);

		// Fill the background with the transparent color
		imagefilledrectangle($overlay, 0, 0, $width, $height, $color);
	}

	// Alpha blending must be enabled on the background!
	imagealphablending($this->_image, TRUE);

	if (imagecopy($this->_image, $overlay, $offset_x, $offset_y, 0, 0, $width, $height))
	{
		// Destroy the overlay image
		imagedestroy($overlay);
	}
}

protected _load_image( ) (defined in Kohana_Image_GD)

Loads an image into GD.

Return Values

  • void

Source Code

protected function _load_image()
{
	if ( ! is_resource($this->_image))
	{
		// Gets create function
		$create = $this->_create_function;

		// Open the temporary image
		$this->_image = $create($this->file);

		// Preserve transparency when saving
		imagesavealpha($this->_image, TRUE);
	}
}

protected _save_function( string $extension , integer & $quality ) (defined in Kohana_Image_GD)

Get the GD saving function and image type for this extension. Also normalizes the quality setting

Parameters

  • string $extension required - Image type: png, jpg, etc
  • byref integer $quality required - Image quality

Tags

Return Values

  • array - Save function, IMAGETYPE_* constant

Source Code

protected function _save_function($extension, & $quality)
{
	if ( ! $extension)
	{
		// Use the current image type
		$extension = image_type_to_extension($this->type, FALSE);
	}

	switch (strtolower($extension))
	{
		case 'jpg':
		case 'jpeg':
			// Save a JPG file
			$save = 'imagejpeg';
			$type = IMAGETYPE_JPEG;
		break;
		case 'gif':
			// Save a GIF file
			$save = 'imagegif';
			$type = IMAGETYPE_GIF;

			// GIFs do not a quality setting
			$quality = NULL;
		break;
		case 'png':
			// Save a PNG file
			$save = 'imagepng';
			$type = IMAGETYPE_PNG;

			// Use a compression level of 9 (does not affect quality!)
			$quality = 9;
		break;
		default:
			throw new Kohana_Exception('Installed GD does not support :type images',
				array(':type' => $extension));
		break;
	}

	return array($save, $type);
}