ImageUtil is a PHP class for intelligently resizing images.** cropScale: Given a 640 x 480 image and 240 x 240 target dimension, the image will first be scaled to 320 x 240, then center-cropped to 240 x 240. (compares scale factor of both dimensions and picks closest value to original then center-crops the other)** fitScale: The same image and t…

example.php

<?
require('ImageUtil.class.php');

$imageUtil = new ImageUtil();

$imageUtil->loadImage('path/to/photo.jpg');

// center-crop image to 310x50
$imageUtil->crop(310,50,'center','center');

// other sizing/cropping examples:

// crop image to 310x50 starting from x:80, y:100
// $imageUtil->crop(310,50,80,100);

// crop-scale image into 200x200. This mode will always result in output exactly the size spec'd
// $imageUtil->cropScale(200,200);

// fit-scal image into 200X200. This mode will result in image no larger than 200x200, but if source image not square, 
// the shorter dimension will be less than spec'd
// $imageUtil->fitScale(200,200);

// uses defaults to write output to browser (format: jpeg, quality: 75%)
$imageUtil->writeImage();

// other write examples

// write 60% quality jpeg to file
// $imageUtil->writeImage('path/to/output.jpg',ImageUtil::JPEG,60);

// write 90% quality png to browser
// $imageUtil->writeImage(NULL,ImageUtil::PNG,90);

// write gif to file (GIF writes ignore quality setting)
// $imageUtil->writeImage('path/to/output.gif',ImageUtil::GIF);
?>

imagebmp.inc.php

<?php
/*
*------------------------------------------------------------
*                   BMP Image functions
*------------------------------------------------------------
*                      By JPEXS
*/




/*
*------------------------------------------------------------
*                    ImageBMP
*------------------------------------------------------------
*            - Creates new BMP file
*
*         Parameters:  $img - Target image
*                      $file - Target file to store
*                            - if not specified, bmp is returned
*
*           Returns: if $file specified - true if OK
                     if $file not specified - image data
*/
function imagebmp($img,$file="",$RLE=0)
{


$ColorCount=imagecolorstotal($img);

$Transparent=imagecolortransparent($img);
$IsTransparent=$Transparent!=-1;


if($IsTransparent) $ColorCount--;

if($ColorCount==0) {$ColorCount=0; $BitCount=24;};
if(($ColorCount>0)and($ColorCount<=2)) {$ColorCount=2; $BitCount=1;};
if(($ColorCount>2)and($ColorCount<=16)) { $ColorCount=16; $BitCount=4;};
if(($ColorCount>16)and($ColorCount<=256)) { $ColorCount=0; $BitCount=8;};


                $Width=imagesx($img);
                $Height=imagesy($img);

                $Zbytek=(4-($Width/(8/$BitCount))%4)%4;

                if($BitCount<24) $palsize=pow(2,$BitCount)*4;

                $size=(floor($Width/(8/$BitCount))+$Zbytek)*$Height+54;
                $size+=$palsize;
                $offset=54+$palsize;

                // Bitmap File Header
                $ret = 'BM';                        // header (2b)
                $ret .= int_to_dword($size);        // size of file (4b)
                $ret .= int_to_dword(0);        // reserved (4b)
                $ret .= int_to_dword($offset);        // byte location in the file which is first byte of IMAGE (4b)
                // Bitmap Info Header
                $ret .= int_to_dword(40);        // Size of BITMAPINFOHEADER (4b)
                $ret .= int_to_dword($Width);        // width of bitmap (4b)
                $ret .= int_to_dword($Height);        // height of bitmap (4b)
                $ret .= int_to_word(1);        // biPlanes = 1 (2b)
                $ret .= int_to_word($BitCount);        // biBitCount = {1 (mono) or 4 (16 clr ) or 8 (256 clr) or 24 (16 Mil)} (2b)
                $ret .= int_to_dword($RLE);        // RLE COMPRESSION (4b)
                $ret .= int_to_dword(0);        // width x height (4b)
                $ret .= int_to_dword(0);        // biXPelsPerMeter (4b)
                $ret .= int_to_dword(0);        // biYPelsPerMeter (4b)
                $ret .= int_to_dword(0);        // Number of palettes used (4b)
                $ret .= int_to_dword(0);        // Number of important colour (4b)
                // image data

                $CC=$ColorCount;
                $sl1=strlen($ret);
                if($CC==0) $CC=256;
                if($BitCount<24)
                   {
                    $ColorTotal=imagecolorstotal($img);
                     if($IsTransparent) $ColorTotal--;

                     for($p=0;$p<$ColorTotal;$p++)
                     {
                      $color=imagecolorsforindex($img,$p);
                       $ret.=inttobyte($color["blue"]);
                       $ret.=inttobyte($color["green"]);
                       $ret.=inttobyte($color["red"]);
                       $ret.=inttobyte(0); //RESERVED
                     };

                    $CT=$ColorTotal;
                  for($p=$ColorTotal;$p<$CC;$p++)
                       {
                      $ret.=inttobyte(0);
                      $ret.=inttobyte(0);
                      $ret.=inttobyte(0);
                      $ret.=inttobyte(0); //RESERVED
                     };
                   };


if($BitCount<=8)
{

 for($y=$Height-1;$y>=0;$y--)
 {
  $bWrite="";
  for($x=0;$x<$Width;$x++)
   {
   $color=imagecolorat($img,$x,$y);
   $bWrite.=decbinx($color,$BitCount);
   if(strlen($bWrite)==8)
    {
     $retd.=inttobyte(bindec($bWrite));
     $bWrite="";
    };
   };

  if((strlen($bWrite)<8)and(strlen($bWrite)!=0))
    {
     $sl=strlen($bWrite);
     for($t=0;$t<8-$sl;$t++)
      $sl.="0";
     $retd.=inttobyte(bindec($bWrite));
    };
 for($z=0;$z<$Zbytek;$z++)
   $retd.=inttobyte(0);
 };
};

if(($RLE==1)and($BitCount==8))
{
 for($t=0;$t<strlen($retd);$t+=4)
  {
   if($t!=0)
   if(($t)%$Width==0)
    $ret.=chr(0).chr(0);

   if(($t+5)%$Width==0)
   {
     $ret.=chr(0).chr(5).substr($retd,$t,5).chr(0);
     $t+=1;
   }
   if(($t+6)%$Width==0)
    {
     $ret.=chr(0).chr(6).substr($retd,$t,6);
     $t+=2;
    }
    else
    {
     $ret.=chr(0).chr(4).substr($retd,$t,4);
    };
  };
  $ret.=chr(0).chr(1);
}
else
{
$ret.=$retd;
};


                if($BitCount==24)
                {
                for($z=0;$z<$Zbytek;$z++)
                 $Dopl.=chr(0);

                for($y=$Height-1;$y>=0;$y--)
                 {
                 for($x=0;$x<$Width;$x++)
                        {
                           $color=imagecolorsforindex($img,ImageColorAt($img,$x,$y));
                           $ret.=chr($color["blue"]).chr($color["green"]).chr($color["red"]);
                        }
                 $ret.=$Dopl;
                 };

                 };

  if($file!="")
   {
    $r=($f=fopen($file,"w"));
    $r=$r and fwrite($f,$ret);
    $r=$r and fclose($f);
    return $r;
   }
  else
  {
   echo $ret;
  };
};

/*
*------------------------------------------------------------
*                    ImageCreateFromBmp
*------------------------------------------------------------
*            - Reads image from a BMP file
*
*         Parameters:  $file - Target file to load
*
*            Returns: Image ID
*/

function imagecreatefrombmp($file)
{
global  $CurrentBit, $echoMode;

$f=fopen($file,"r");
$Header=fread($f,2);

if($Header=="BM")
{
 $Size=freaddword($f);
 $Reserved1=freadword($f);
 $Reserved2=freadword($f);
 $FirstByteOfImage=freaddword($f);

 $SizeBITMAPINFOHEADER=freaddword($f);
 $Width=freaddword($f);
 $Height=freaddword($f);
 $biPlanes=freadword($f);
 $biBitCount=freadword($f);
 $RLECompression=freaddword($f);
 $WidthxHeight=freaddword($f);
 $biXPelsPerMeter=freaddword($f);
 $biYPelsPerMeter=freaddword($f);
 $NumberOfPalettesUsed=freaddword($f);
 $NumberOfImportantColors=freaddword($f);

if($biBitCount<24)
 {
  $img=imagecreate($Width,$Height);
  $Colors=pow(2,$biBitCount);
  for($p=0;$p<$Colors;$p++)
   {
    $B=freadbyte($f);
    $G=freadbyte($f);
    $R=freadbyte($f);
    $Reserved=freadbyte($f);
    $Palette[]=imagecolorallocate($img,$R,$G,$B);
   };




if($RLECompression==0)
{
   $Zbytek=(4-ceil(($Width/(8/$biBitCount)))%4)%4;

for($y=$Height-1;$y>=0;$y--)
    {
     $CurrentBit=0;
     for($x=0;$x<$Width;$x++)
      {
         $C=freadbits($f,$biBitCount);
       imagesetpixel($img,$x,$y,$Palette[$C]);
      };
    if($CurrentBit!=0) {freadbyte($f);};
    for($g=0;$g<$Zbytek;$g++)
     freadbyte($f);
     };

 };
};


if($RLECompression==1) //$BI_RLE8
{
$y=$Height;

$pocetb=0;

while(true)
{
$y--;
$prefix=freadbyte($f);
$suffix=freadbyte($f);
$pocetb+=2;

$echoit=false;

if($echoit)echo "Prefix: $prefix Suffix: $suffix<BR>";
if(($prefix==0)and($suffix==1)) break;
if(feof($f)) break;

while(!(($prefix==0)and($suffix==0)))
{
 if($prefix==0)
  {
   $pocet=$suffix;
   $Data.=fread($f,$pocet);
   $pocetb+=$pocet;
   if($pocetb%2==1) {freadbyte($f); $pocetb++;};
  };
 if($prefix>0)
  {
   $pocet=$prefix;
   for($r=0;$r<$pocet;$r++)
    $Data.=chr($suffix);
  };
 $prefix=freadbyte($f);
 $suffix=freadbyte($f);
 $pocetb+=2;
 if($echoit) echo "Prefix: $prefix Suffix: $suffix<BR>";
};

for($x=0;$x<strlen($Data);$x++)
 {
  imagesetpixel($img,$x,$y,$Palette[ord($Data[$x])]);
 };
$Data="";

};

};


if($RLECompression==2) //$BI_RLE4
{
$y=$Height;
$pocetb=0;

/*while(!feof($f))
 echo freadbyte($f)."_".freadbyte($f)."<BR>";*/
while(true)
{
//break;
$y--;
$prefix=freadbyte($f);
$suffix=freadbyte($f);
$pocetb+=2;

$echoit=false;

if($echoit)echo "Prefix: $prefix Suffix: $suffix<BR>";
if(($prefix==0)and($suffix==1)) break;
if(feof($f)) break;

while(!(($prefix==0)and($suffix==0)))
{
 if($prefix==0)
  {
   $pocet=$suffix;

   $CurrentBit=0;
   for($h=0;$h<$pocet;$h++)
    $Data.=chr(freadbits($f,4));
   if($CurrentBit!=0) freadbits($f,4);
   $pocetb+=ceil(($pocet/2));
   if($pocetb%2==1) {freadbyte($f); $pocetb++;};
  };
 if($prefix>0)
  {
   $pocet=$prefix;
   $i=0;
   for($r=0;$r<$pocet;$r++)
    {
    if($i%2==0)
     {
      $Data.=chr($suffix%16);
     }
     else
     {
      $Data.=chr(floor($suffix/16));
     };
    $i++;
    };
  };
 $prefix=freadbyte($f);
 $suffix=freadbyte($f);
 $pocetb+=2;
 if($echoit) echo "Prefix: $prefix Suffix: $suffix<BR>";
};

for($x=0;$x<strlen($Data);$x++)
 {
  imagesetpixel($img,$x,$y,$Palette[ord($Data[$x])]);
 };
$Data="";

};

};


 if($biBitCount==24)
{
 $img=imagecreatetruecolor($Width,$Height);
 $Zbytek=$Width%4;

   for($y=$Height-1;$y>=0;$y--)
    {
     for($x=0;$x<$Width;$x++)
      {
       $B=freadbyte($f);
       $G=freadbyte($f);
       $R=freadbyte($f);
       $color=imagecolorexact($img,$R,$G,$B);
       if($color==-1) $color=imagecolorallocate($img,$R,$G,$B);
       imagesetpixel($img,$x,$y,$color);
      }
    for($z=0;$z<$Zbytek;$z++)
     freadbyte($f);
   };
};
return $img;

};


fclose($f);


};





/*
* Helping functions:
*-------------------------
*
* freadbyte($file) - reads 1 byte from $file
* freadword($file) - reads 2 bytes (1 word) from $file
* freaddword($file) - reads 4 bytes (1 dword) from $file
* freadlngint($file) - same as freaddword($file)
* decbin8($d) - returns binary string of d zero filled to 8
* RetBits($byte,$start,$len) - returns bits $start->$start+$len from $byte
* freadbits($file,$count) - reads next $count bits from $file
* RGBToHex($R,$G,$B) - convert $R, $G, $B to hex
* int_to_dword($n) - returns 4 byte representation of $n
* int_to_word($n) - returns 2 byte representation of $n
*/

function freadbyte($f)
{
 return ord(fread($f,1));
};

function freadword($f)
{
 $b1=freadbyte($f);
 $b2=freadbyte($f);
 return $b2*256+$b1;
};


function freadlngint($f)
{
return freaddword($f);
};

function freaddword($f)
{
 $b1=freadword($f);
 $b2=freadword($f);
 return $b2*65536+$b1;
};



function RetBits($byte,$start,$len)
{
$bin=decbin8($byte);
$r=bindec(substr($bin,$start,$len));
return $r;

};



$CurrentBit=0;
function freadbits($f,$count)
{
 global $CurrentBit,$SMode;
 $Byte=freadbyte($f);
 $LastCBit=$CurrentBit;
 $CurrentBit+=$count;
 if($CurrentBit==8)
  {
   $CurrentBit=0;
  }
 else
  {
   fseek($f,ftell($f)-1);
  };
 return RetBits($Byte,$LastCBit,$count);
};



function RGBToHex($Red,$Green,$Blue)
  {
   $hRed=dechex($Red);if(strlen($hRed)==1) $hRed="0$hRed";
   $hGreen=dechex($Green);if(strlen($hGreen)==1) $hGreen="0$hGreen";
   $hBlue=dechex($Blue);if(strlen($hBlue)==1) $hBlue="0$hBlue";
   return($hRed.$hGreen.$hBlue);
  };

        function int_to_dword($n)
        {
                return chr($n & 255).chr(($n >> 8) & 255).chr(($n >> 16) & 255).chr(($n >> 24) & 255);
        }
        function int_to_word($n)
        {
                return chr($n & 255).chr(($n >> 8) & 255);
        }


function decbin8($d)
{
return decbinx($d,8);
};

function decbinx($d,$n)
{
$bin=decbin($d);
$sbin=strlen($bin);
for($j=0;$j<$n-$sbin;$j++)
 $bin="0$bin";
return $bin;
};

function inttobyte($n)
{
return chr($n);
};
//***************************************************************************
//***************************************************************************
//END BMP FUNCTIONS
//***************************************************************************
//***************************************************************************

?>

ImageUtil.class.php

<?php
/**
** Written by Steven Settlemyre
** http://sixninefive.com
**
** class: ImageUtil
** description: Utility class for scaling and cropping images
*/


class ImageUtil{

  public $dstImg;
  public $srcImg;
  public $width;
  public $height;
  public $srcImgProps;

  const CROP_SCALE = "cropScale";
  const FIT_SCALE = "fitScale";
  const CROP = "crop";

  const JPEG = "jpeg";
  const GIF = "gif";
  const PNG = "png";


  // shortcut method. kinda...
  public function resize($newWidth='',$newHeight='',$mode='cropScale'){
    switch($mode){
      case self::FIT_SCALE:
        $this->fitScale($newWidth,$newHeight);
        break;
      case self::CROP:
        $this->crop($newWidth,$newHeight,'center','center');
        break;
      case self::CROP_SCALE:
      default:
        $this->cropScale($newWidth,$newHeight);
        break;
    }
  }
  
  // will resize an image to fit within the given dimensions while preserving aspect ratio
  // Example: source dimensions - 600x200
  //      target dimensions - 300x300
  //      result dimensions - 300x100 (scaled by .5)
  public function fitScale($newWidth,$newHeight){
    // get sizes of source image
    $src_w = imagesx($this->srcImg);
    $src_h = imagesy($this->srcImg);

    // see which way to scale
    $scale = min($newWidth/$src_w,$newHeight/$src_h);
    
    // if image larger than dimensions
    if($scale <= 1){
      $tmp_w = $src_w*$scale;
      $tmp_h = $src_h*$scale;

    // if dimensions larger than image (dont scale up)
    }else{
      $tmp_w = $src_w;
      $tmp_h = $src_h;
    }
    $this->dstImg = imagecreatetruecolor($tmp_w,$tmp_h);

    imagecopyresampled($this->dstImg,$this->srcImg,0,0,0,0,$tmp_w,$tmp_h,$src_w,$src_h);
  }

  // will resize image to fill the target space with best fit, cropping the larger dimension
  public function cropScale($newWidth,$newHeight){
    
    // get sizes of source image
    $src_w = imagesx($this->srcImg);
    $src_h = imagesy($this->srcImg);

    // see which way to scale
    $scale = max($newWidth/$src_w,$newHeight/$src_h);
    $tmp_w = $src_w*$scale;
    $tmp_h = $src_h*$scale;
    $tmp = imagecreatetruecolor($tmp_w,$tmp_h);
    $this->dstImg = imagecreatetruecolor($newWidth,$newHeight);

    // resize the image preserving aspect ratio
    imagecopyresampled($tmp,$this->srcImg,0,0,0,0,$tmp_w,$tmp_h,$src_w,$src_h);

    // crop the resized image to the target dimensions
    imagecopyresampled($this->dstImg,$tmp,0,0,intval(($tmp_w-$newWidth)/2),intval(($tmp_h-$newHeight)/2),$newWidth,$newHeight,$newWidth,$newHeight);
  }

  // will center-crop image to target dimensions
  public function crop($newWidth,$newHeight,$x = 'center',$y = 'center'){
    
    // get sizes of source image
    $src_w = imagesx($this->srcImg);
    $src_h = imagesy($this->srcImg);

    if($x == 'center'){
      $x = ($src_w-$newWidth)/2;
    }else if(is_numeric($x)){
      $x = intval($x);
    }else{
      $x = 0;
    }
    if($y == 'center'){
      $y = ($src_h-$newHeight)/2;
    }else if(is_numeric($y)){
      $y = intval($y);
    }else{
      $y = 0;
    }

    // see which way to scale
    $this->dstImg = imagecreatetruecolor($newWidth,$newHeight);

    // crop the image to the target dimensions
    imagecopy($this->dstImg,$this->srcImg,0,0,$x,$y,$newWidth,$newHeight);
  }

  public function loadImage($filename){
    
    // get image properties
    $this->srcImgProps = @getimagesize($filename) or die("Failed reading $filename");// or $this->warningImage('creation');
    
    // read in source image
    switch($this->srcImgProps[2]){
      case 1:
        $this->srcImg = @imagecreatefromgif($filename) or $this->warningImage('creation');
        break;
      case 2:
        $this->srcImg = @imagecreatefromjpeg($filename) or $this->warningImage('creation');
        break;
      case 3:
        $this->srcImg = @imagecreatefrompng($filename) or $this->warningImage('creation');
        break;
      case 6:
      case 15:
        $this->srcImg = @imagecreatefrombmp($filename) or $this->warningImage('creation');
        break;
      default:
        $this->warningImage('creation');
    }
    return(true);
  }

  public function warningImage($warning='?'){
    $white = imagecolorallocate($this->dstImg, 255, 255, 255);
    $red = imagecolorallocate($this->dstImg, 255,0,0);
    imagefilledrectangle($this->dstImg,0,0,$this->width,$this->height,$white);
    imagestring($this->dstImg,5,10,10,$warning,$red);
  }

  public function writeImage($outFile = NULL, $format = 'jpeg', $quality = 75){

    $quality = intval(max(0,min(100,$quality)));

    if ($format == ImageUtil::JPEG) {
      if(!$outFile){
        header ("Content-type: image/jpeg");
      }
      imagejpeg($this->dstImg,$outFile,$quality);
    }else if($format == ImageUtil::GIF){
      if(!$outFile){
        header ("Content-type: image/gif");
      }
      imagegif($this->dstImg,$outFile);

    }else if($format == ImageUtil::PNG){
      if(!$outFile){
        header ("Content-type: image/png");
      }
      imagejpeg($this->dstImg,$outFile,$quality);

    }
  }
}
?>