Image Resize function

[Derokorian]

I've created an image resizing function, and attempted to comment it to phpdoc style as best I can. Let me know what you think:

imageresize.php

<?php
/**
 * This function resizes a given image into the target file with the given width and height
 *
 * @author Ryan Pallas
 * @version 1.0
 * 
 * @param string $src Source input file to be resized, with full path
 * @param string $target Target output after resizing, with full path
 * @param int $newWidth Target width
 * @param int $newHeight Target height
 * @param bool $abs Whether newwidth/newheight are final or maximum measurements (Default: FALSE)
 *
 * @return bool
 */
function imageResize($src,$target,$newWidth,$newHeight,$abs=FALSE)
	{

$sizeInfo = getimagesize($src);
if($sizeInfo == FALSE) return FALSE; // Not an image, exit and return FALSE
list($origWidth,$origHeight) = $sizeInfo;  // Get original dimensions
if( !$abs )
	{
	// determine new width & height based on aspect ratio
	$ratio = (($origWidth / $origHeight) > ($newWidth / $newHeight)) ? $newWidth / $origWidth : $newHeight / $origHeight; 
	$newWidth = (int) ($origWidth * $ratio); // set width with ratio
	$newHeight = (int) ($origHeight * $ratio); // set height with ratio
	if( $origHeight <= $newHeight && $origWidth <= $newWidth)
		{
		$newHeight = $origHeight;
		$newWidth = $origWidth;
	}
	$xOffset = 0;
	$yOffset = 0;
} else
	{
	// set original sampling area based on exact new dimensions
	$ratio = (($origWidth / $origHeight) < ($newWidth / $newHeight)) ? $newWidth / $origWidth : $newHeight / $origHeight; 
	$finalHeight = (int) floor($newHeight / $ratio);
	$finalWidth = (int) floor($newWidth / $ratio);

	$yOffset = ($finalHeight == $origHeight) ? 0 : floor( ($origHeight-$finalHeight)/2 );
	$xOffset = ($finalWidth == $origWidth) ?  0 : floor( ($origWidth-$finalWidth)/2 );
	$origHeight = $finalHeight;
	$origWidth = $finalWidth;
}

// determine file type for correct functions
$fileinfo = pathinfo($src);
$ext = $fileinfo['extension'];
switch(strtolower($ext))
	{ 
	case "jpg": 
	case "jpeg": 
		$create = "imagecreatefromjpeg"; 
		$move = "imagejpeg"; 
		break; 
	case "gif": 
		$create = "imagecreatefromgif"; 
		$move = "imagegif"; 
		break; 
	case "png": 
		$create = "imagecreatefrompng"; 
		$move = "imagepng"; 
		break; 
	case "bmp": 
		$create = "imagecreatefromwbmp"; 
		$move = "imagewbmp"; 
		break; 
	default: 
		return FALSE; 
} 
$base = $create($src);  // open source
$temp = imagecreatetruecolor($newWidth,$newHeight); //create new file
imagecopyresampled($temp,$base,0,0,$xOffset,$yOffset,$newWidth,$newHeight,$origWidth,$origHeight); // resample source into new file
if ( $move($temp,$target) )
	{
	// copy new file to target location, if successful return true otherwise return false.
	return TRUE;
} else
	{
	return FALSE;
}
}

[Derokorian]

Updated with suggestions from a couple other forums (as well as improved comments). Please let me know where this can be improved or functionality you feel was left out.

/**
 * This function resizes a given image into the target file with the given width and height
 *
 * @author Ryan Pallas
 * @version 1.0
 * @since 0.4
 * 
 * @access private
 * @param string $src Source input file to be resized
 * @param string $target Target output after resizing
 * @param int $newWidth Target width
 * @param int $newHeight Target height
 * @param bool $abs Whether newwidth/newheight are final or maximum measurements (Default: FALSE)
 *
 * @return bool
 */
private function _imageResize($src,$target,$newWidth,$newHeight,$abs=FALSE)
	{
	/**
	 * @var array source image info
	 */
	$imgInfo = getimagesize($src);

/**
 * return false if not an image
 */
if($imgInfo == FALSE) return FALSE;

/**
 * @var int width
 * @var int height
 * @var constant img type
 */
list($origWidth,$origHeight,$imgtype) = $imgInfo;

/**
 * absolute dimensions or max dimensions
 */
if( !$abs )
	{
	/**
	 * determine new width & height based on aspect ratio
	 */
	$ratio = (($origWidth / $origHeight) > ($newWidth / $newHeight)) ? $newWidth / $origWidth : $newHeight / $origHeight; 
	$newWidth = (int) ($origWidth * $ratio); // set width with ratio
	$newHeight = (int) ($origHeight * $ratio); // set height with ratio

	/**
	 * if original dimensions smaller than new, do not resize
	 */
	if( $origHeight <= $newHeight && $origWidth <= $newWidth)
		{
		$newHeight = $origHeight;
		$newWidth = $origWidth;
	}

	/**
	 * @var int image offset for resampling
	 */
	$xOffset = 0;
	$yOffset = 0;
} else
	{
	/**
	 * set original sampling area based on exact new dimensions
	 */
	$ratio = (($origWidth / $origHeight) < ($newWidth / $newHeight)) ? $newWidth / $origWidth : $newHeight / $origHeight; 
	$finalHeight = (int) floor($newHeight / $ratio);
	$finalWidth = (int) floor($newWidth / $ratio);

	/**
	 * @var int offset to center resampling area on original source
	 */
	$yOffset = ($finalHeight == $origHeight) ? 0 : floor( ($origHeight-$finalHeight)/2 );
	$xOffset = ($finalWidth == $origWidth) ?  0 : floor( ($origWidth-$finalWidth)/2 );

	/**
	 * @var int resampling area of original source
	 */
	$origHeight = $finalHeight;
	$origWidth = $finalWidth;
}

/**
 * determine file type for correct functions
 */
switch($imgtype)
	{ 
	case IMAGETYPE_JPEG: 
		$create = "imagecreatefromjpeg"; 
		$move = "imagejpeg"; 
		break; 
	case IMAGETYPE_GIF: 
		$create = "imagecreatefromgif"; 
		$move = "imagegif"; 
		break; 
	case IMAGETYPE_PNG: 
		$create = "imagecreatefrompng"; 
		$move = "imagepng"; 
		break; 
	case IMAGETYPE_WBMP: 
		$create = "imagecreatefromwbmp"; 
		$move = "imagewbmp"; 
		break; 
	default: 
		return FALSE; 
}

/**
 * @var image create image from source
 */
$base = $create($src);

/**
 * @var image create image to new size
 */
$temp = imagecreatetruecolor($newWidth,$newHeight);

/**
 * copy resampled original and resize to new image
 */
imagecopyresampled($temp,$base,0,0,$xOffset,$yOffset,$newWidth,$newHeight,$origWidth,$origHeight);

/**
 * move new image to destination
 * return true on success, false on failure
 */
if ( $move($temp,$target) )
	{
	return TRUE;
} else
	{
	return FALSE;
}
}

[bradgrafelman]

Er... outside of a class definition, the keyword 'private' before a function not only doesn't make any sense but is also just going to cause parse errors.

So... is that really the code you want us to critique? If so, the only comment I have is to address this error:

Parse error: syntax error, unexpected T_PRIVATE

and post a new copy of the code so we can re-evaluate it without parse errors. 🙂

[Derokorian]

Whoops made the changes in my class forgot to take the class items out 😛 selects the word private, hits delete Also added example code

<?php

/** 
* This function resizes a given image into the target file with the given width and height 
* 
* @author Ryan Pallas 
* @version 1.0 
*
* @example usage
* 	$src = "C:\www\images\uploads\image.jpg";
* 	$targ = "C:\www\images\uploads\thumbs\image.jpg";
* 	if( imageResize($src,$targ,100,75) ) echo "Successfully resized thumbnail";
* 
* @param string $src Source input file to be resized 
* @param string $target Target output after resizing 
* @param int $newWidth Target width 
* @param int $newHeight Target height 
* @param bool $abs Whether newwidth/newheight are final or maximum measurements (Default: FALSE) 
* 
* @return bool 
*/ 
function imageResize($src,$target,$newWidth,$newHeight,$abs=FALSE) 
    { 
    /** 
     * @var array source image info 
     */ 
    $imgInfo = getimagesize($src); 

/** 
 * return false if not an image 
 */ 
if($imgInfo == FALSE) return FALSE; 

/** 
 * @var int width 
 * @var int height 
 * @var constant img type 
 */ 
list($origWidth,$origHeight,$imgtype) = $imgInfo; 

/** 
 * absolute dimensions or max dimensions 
 */ 
if( !$abs ) 
    { 
    /** 
     * determine new width & height based on aspect ratio 
     */ 
    $ratio = (($origWidth / $origHeight) > ($newWidth / $newHeight)) ? $newWidth / $origWidth : $newHeight / $origHeight;
    $newWidth = (int) ($origWidth * $ratio); // set width with ratio 
    $newHeight = (int) ($origHeight * $ratio); // set height with ratio 

    /** 
     * if original dimensions smaller than new, do not resize 
     */ 
    if( $origHeight <= $newHeight && $origWidth <= $newWidth) 
        { 
        $newHeight = $origHeight; 
        $newWidth = $origWidth; 
    } 

    /** 
     * @var int image offset for resampling 
     */ 
    $xOffset = 0; 
    $yOffset = 0; 
} else 
    { 
    /** 
     * set original sampling area based on exact new dimensions 
     */ 
    $ratio = (($origWidth / $origHeight) < ($newWidth / $newHeight)) ? $newWidth / $origWidth : $newHeight / $origHeight;
    $finalHeight = (int) floor($newHeight / $ratio); 
    $finalWidth = (int) floor($newWidth / $ratio); 

    /** 
     * @var int offset to center resampling area on original source 
     */ 
    $yOffset = ($finalHeight == $origHeight) ? 0 : floor( ($origHeight-$finalHeight)/2 ); 
    $xOffset = ($finalWidth == $origWidth) ?  0 : floor( ($origWidth-$finalWidth)/2 ); 

    /** 
     * @var int resampling area of original source 
     */ 
    $origHeight = $finalHeight; 
    $origWidth = $finalWidth; 
} 

/** 
 * determine file type for correct functions 
 */ 
switch($imgtype) 
    { 
    case IMAGETYPE_JPEG: 
        $create = "imagecreatefromjpeg"; 
        $move = "imagejpeg"; 
        break; 
    case IMAGETYPE_GIF: 
        $create = "imagecreatefromgif"; 
        $move = "imagegif"; 
        break; 
    case IMAGETYPE_PNG: 
        $create = "imagecreatefrompng"; 
        $move = "imagepng"; 
        break; 
    case IMAGETYPE_WBMP: 
        $create = "imagecreatefromwbmp"; 
        $move = "imagewbmp"; 
        break; 
    default: 
        return FALSE; 
} 

/** 
 * @var image create image from source 
 */ 
$base = $create($src); 

/** 
 * @var image create image to new size 
 */ 
$temp = imagecreatetruecolor($newWidth,$newHeight); 

/** 
 * copy resampled original and resize to new image 
 */ 
imagecopyresampled($temp,$base,0,0,$xOffset,$yOffset,$newWidth,$newHeight,$origWidth,$origHeight); 

/** 
 * move new image to destination 
 * return true on success, false on failure 
 */ 
if ( $move($temp,$target) ) 
    { 
    return TRUE; 
} else 
    { 
    return FALSE; 
} 
}