Implementation of P4Cms_Image_Driver_Interface using the 'gd' extension. More...

Inheritance diagram for P4Cms_Image_Driver_Gd:

Public Member Functions
	getData ($type=null)
	Return binary image data.
	hasData ()
	Check if there are image data to operate with.
	setData ($data=null)
	Set the image data.
Static Public Member Functions
static	isSupportedType ($type)
	Check if given image type is supported.
Protected Member Functions
	_crop ($width=null, $height=null, $x=0, $y=0)
	Crop the image to the given size and position.
	_getImageHeight ()
	Return image height in pixels.
	_getImageWidth ()
	Return image width in pixels.
	_getType ($imageData)
	Detect image type from a given image data.
	_rotate ($degrees=0)
	Rotate the image.
	_scale ($width=null, $height=null)
	Scale the image to the given size.
	_sharpen ()
	Sharpen the image by applying a default 3x3 matrix passed to the imageconvolution() function.
Protected Attributes
	$_resource = null
	$_type = null
Static Protected Attributes
static	$_requiredExtension = 'gd'
static	$_supportedTransforms

Detailed Description

Implementation of P4Cms_Image_Driver_Interface using the 'gd' extension.

Copyright:: 2011-2012 Perforce Software. All rights reserved

License:: Please see LICENSE.txt in top-level folder of this distribution.

Version:: 2012.2/486814

Member Function Documentation

P4Cms_Image_Driver_Gd::_crop	(	$	width = `null`,
		$	height = `null`,
		$	x = `0`,
		$	y = `0`
	)		`[protected]`

Crop the image to the given size and position.

Parameters:

int \| null	$width	the width in pixels
int \| null	$height	the height in pixels
int	$x	the x coordinate starting position
int	$y	the y coordinate starting position

    {
        if (!$width || !$height) {
            throw new P4Cms_Image_Exception(
                'Both width and height are required.'
            );
        }

        // crop the image
        $dst = imagecreatetruecolor($width, $height);
        imagecopy(
            $dst,
            $this->_resource,
            0,
            0,
            $x,
            $y,
            $width,
            $height
        );
        $this->_resource = $dst;
    }

P4Cms_Image_Driver_Gd::_getImageHeight ( ) [protected]

Return image height in pixels.

Returns:: int image height in pixels

Reimplemented from P4Cms_Image_Driver_Abstract.

    {
        return imagesy($this->_resource);
    }

P4Cms_Image_Driver_Gd::_getImageWidth ( ) [protected]

Return image width in pixels.

Returns:: int image width in pixels

Reimplemented from P4Cms_Image_Driver_Abstract.

    {
        return imagesx($this->_resource);
    }

P4Cms_Image_Driver_Gd::_getType ( $ imageData ) [protected]

Detect image type from a given image data.

Parameters:

string $imageData data representing image to detect type on

Returns:: string image type (jpeg, gif etc.)

Exceptions:

P4Cms_Image_Exception if image type cannot be determined

    {
        // try to get image type from 'finfo' if its available
        if (class_exists('finfo')) {
            $finfo = new finfo(FILEINFO_MIME_TYPE);
            $mime  = $finfo->buffer($imageData);

            return str_replace('image/', '', $mime);
        }

        throw new P4Cms_Image_Exception('Cannot determine image type.');
    }

P4Cms_Image_Driver_Gd::_rotate ( $ degrees = 0 ) [protected]

Rotate the image.

Parameters:

float $degrees the rotation angle

    {
        $this->_resource = imagerotate($this->_resource, $degrees, 0);
    }

P4Cms_Image_Driver_Gd::_scale	(	$	width = `null`,
		$	height = `null`
	)		`[protected]`

Scale the image to the given size.

Parameters:

int	$width	the width in pixels
int	$height	the height in pixels

    {
        if (!$width && !$height) {
            throw new P4Cms_Image_Exception(
                'At least one of width or height is required.'
            );
        }

        // calculate original image aspect ratio
        $sourceWidth  = $this->_getImageWidth();
        $sourceHeight = $this->_getImageHeight();
        $ratio        = $sourceWidth / $sourceHeight;

        // if only one dimension is given, calculate the another one such
        // that new image keeps same ratio as the original
        if (!$width) {
            $width  = round($height * $ratio);
        } else if (!$height) {
            $height = round($width / $ratio);
        }

        // resize the image
        $dst = imagecreatetruecolor($width, $height);
        imagecopyresized(
            $dst,
            $this->_resource,
            0,
            0,
            0,
            0,
            $width,
            $height,
            $sourceWidth,
            $sourceHeight
        );
        $this->_resource = $dst;
    }

P4Cms_Image_Driver_Gd::_sharpen ( ) [protected]

Sharpen the image by applying a default 3x3 matrix passed to the imageconvolution() function.

    {
        $matrix  = array(
            array( 0.0, -1.0,  0.0),
            array(-1.0,  5.0, -1.0),
            array( 0.0, -1.0,  0.0)
        );
        $divisor = array_sum(array_map('array_sum', $matrix));

        // sharpen image by using image convolution
        imageconvolution(
            $this->_resource,
            $matrix,
            $divisor,
            0
        );
    }

P4Cms_Image_Driver_Gd::getData ( $ type = null )

Return binary image data.

Parameters:

string $type optional - the image format (will return image data in the same format as input if not provided)

Returns:: string|null binary image data or null if no image data were set

Implements P4Cms_Image_Driver_Interface.

    {
        // early exit if there are no image data
        if (!$this->hasData()) {
            return null;
        }

        // if no image type was provided, use the type of input image
        $type = $type ?: $this->_type;

        // check if given type is supported
        if (!static::isSupportedType($type)) {
            throw new P4Cms_Image_Exception("Image type '$type' is not supported.");
        }

        // assemble callback to get the image data in a given type
        // @todo should we normalize jpg/jpeg as there is imagejpeg() function but no imagejpg()
        $callback = 'image' . strtolower($type);

        // get image data
        ob_start();
        call_user_func($callback, $this->_resource);
        $data = ob_get_contents();
        ob_end_clean();

        return $data;
    }

P4Cms_Image_Driver_Gd::hasData ( )

Check if there are image data to operate with.

Returns:: bool true if there has been image data set, false otherwise.

Implements P4Cms_Image_Driver_Interface.

    {
        return $this->_resource !== null;
    }

static P4Cms_Image_Driver_Gd::isSupportedType ( $ type ) [static]

Check if given image type is supported.

Parameters:

string $type image type to check for

Returns:: bool true if given image type is supported, false otherwise

Implements P4Cms_Image_Driver_Interface.

    {
        $constant = 'IMG_' . strtoupper($type);
        return defined($constant) && (imagetypes() & constant($constant));
    }

P4Cms_Image_Driver_Gd::setData ( $ data = null )

Set the image data.

Parameters:

string | null $data optional - image data

Returns:: P4Cms_Image_Driver_Gd provides fluent interface

Implements P4Cms_Image_Driver_Interface.

    {
        if ($data) {
            $this->_resource = imagecreatefromstring($data);
            $this->_type     = $this->_getType($data);
        } else {
            $this->_resource = null;
            $this->_type     = null;
        }
        return $this;
    }

Member Data Documentation

P4Cms_Image_Driver_Gd::$_requiredExtension = 'gd' [static, protected]

Reimplemented from P4Cms_Image_Driver_Abstract.

P4Cms_Image_Driver_Gd::$_resource = null [protected]

P4Cms_Image_Driver_Gd::$_supportedTransforms [static, protected]

Initial value:

 array(
        'scale',
        'sharpen',
        'crop',
        'rotate'
    )

Reimplemented from P4Cms_Image_Driver_Abstract.

P4Cms_Image_Driver_Gd::$_type = null [protected]

The documentation for this class was generated from the following file:

Gd.php

P4Cms_Image_Driver_Gd Class Reference

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Member Function Documentation

Member Data Documentation