imagecopyresampled

add a note User Contributed Notes

spencejames2000 at yahoo dot co dot uk
13-May-2006 09:27


For anyone suffering from the srcX and srcY bug (some versions of gd ignore them completely - see http://bugs.php.net/bug.php?id=12780 for details), a quick solution is to use this code snippet:



<?php

function imgcopyresampled(&$dst_img, $src_img, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h)

{

    $tmp_img = imagecreatetruecolor($src_w, $src_h);

    $rv2 = imagecopy($tmp_img, $src_img, 0,0, $src_x, $src_y, $src_w, $src_h);

    $rv1 = imagecopyresampled($dst_img, $tmp_img, $dst_x,$dst_y, 0,0, $dst_w, $dst_h, $src_w, $src_h);

    imagedestroy($tmp_img);

    return($rv1 and $rv2);

}

?>



By using imagecopy to extract the relevant portion of the source image, it works a lot more quickly than pike's solution below, and also without the extra blur.



It may be useful to use override_function in existing projects, although I have not tested this myself.

Tyron Madlener (tyron.at)
11-May-2006 04:43


Creating a thumbnail (120x90 pixel) of a big image (3000x2000 pixel) took me about 5 seconds with imagecopyresampled()



Thats pretty much, so I tested a little how I could improve the speed. I found that imagecopyresized is way faster but results in poor quality.

So I combined both - I first reduce the big image via imagecopyresized to 1024x768 pixel and then create the small thumbnail via imagecopyresampled. The resulting quality is almost the same. In my tests, resizing took only about 2.2 seconds now - twice as fast :)



I also tried using that bicubic image resizing function in some earlier post here, but it was only faster when the thumbnails were smaller than 120x90 and the quality was not very good.



Here's the code if you wanna (I guess there are still a few possibilites to do some more optimiztions tough):



<?php

function CreateThumb($file,$maxwdt,$maxhgt, $dest) {

    list($owdt,$ohgt,$otype)=@getimagesize($file);



  switch($otype) {

    case 1:  $newimg=imagecreatefromgif($file); break;

    case 2:  $newimg=imagecreatefromjpeg($file); break;

    case 3:  $newimg=imagecreatefrompng($file); break;

    default: echo "Unkown filetype (file $file, typ $otype)"; return;

  }

    

  if($newimg) {

    if($owdt>1500 || $ohgt>1200)

            list($owdt, $ohgt) = Resample($newimg, $owdt, $ohgt, 1024,768,0);

            

    Resample($newimg, $owdt, $ohgt, $maxwdt, $maxhgt);

        

        if(!$dest) return $newimg;

        

        if(!is_dir(dirname($dest)))

            mkdir(dirname($dest));

    

    switch($otype) {

      case 1: imagegif($newimg,dest); break;     

      case 2: imagejpeg($newimg,$dest,90); break; 

      case 3: imagepng($newimg,$dest);  break; 

    }

        

        imagedestroy($newimg);

    

    chmod($dest,0644);

  }

}



function Resample(&$img, $owdt, $ohgt, $maxwdt, $maxhgt, $quality=1) { 

  if(!$maxwdt) $divwdt=0;

   else $divwdt=Max(1,$owdt/$maxwdt);

   

  if(!$maxhgt) $divhgt=0;

   else $divhgt=Max(1,$ohgt/$maxhgt);

    

  if($divwdt>=$divhgt) {

    $newwdt=$maxwdt;

    $newhgt=round($ohgt/$divwdt);

  } else {

    $newhgt=$maxhgt;

    $newwdt=round($owdt/$divhgt);

  }

    

    $tn=imagecreatetruecolor($newwdt,$newhgt);

    if($quality)

        imagecopyresampled($tn,$img,0,0,0,0,$newwdt,$newhgt,$owdt,$ohgt);        

    else 

        imagecopyresized($tn,$img,0,0,0,0,$newwdt,$newhgt,$owdt,$ohgt);



    imagedestroy($img);

    

    $img = $tn;

    

    return array($newwdt, $newhgt);

}

?>

mracek at xko dot cz
09-Mar-2006 04:01


Here is function which:

- resize and crop (crop format 4:3 or 1:1)

- methode resample/resize

- open jpg, gif, bmp, png

- save jpg (85%), gif, bmp, png

- show images



$FILE_MIMES = array(

'image/pjpeg'=>"jpg",

'image/jpeg'=>"jpg",

'image/jpg'=>"jpg",

'image/png'=>"png",

'image/x-png'=>"png",

'image/gif'=>"gif",

'image/bmp'=>"bmp");

$FILE_EXTS  = array('.jpeg','.jpg','.png','.gif','.bmp');

$MAX_SIZE  = 16777216;



$lng=array(

's_imgDimension'=>array(

       "80",

       "320"

       ),

's_imgCrop'    =>array(

       "- auto -",

       "na sirku",

       "na vysku",

       "ctverec",

       "- zadne -"

       ),

's_imgFormat'    =>array(

       "4/3",

       "1/1"

       ),

's_imgType'    =>array(

       "jpg",

       "png",

       "gif",

       "bmp"

       ),

's_imgMethode'    =>array(

       "resample",

       "resize"

       )

);



function PPimageTransform($photo1,$type1,$dim,$crop,

$format,$methode,$photo2,$type2)

{

if ($photo1!=="" && File_Exists($photo1))

{

   if (!($crop>0 && $crop<5)) $crop=0;

   width=x"

   list($w,$h) = GetImageSize($photo1);

   $w=($w<1)?1:$w;

   $h=($h<1)?1:$h;

   $wh=$w/$h;



   // format

   $format=($format=='4/3')?4/3:1;



   // auto crop

   if ($crop==0)

       {

       $z1=$format-  ($format-1)/2;

       $z2=$format+(1-$format-1)/2;

           if ($wh>$z1) {$crop=1;}

       elseif ($wh<$z2) {$crop=2;}

       else        {$crop=3;}

       }



   // scale

   if ($crop==4)

       {

       $a=$w>$h?$w:$h;

       $scale=$dim/$a;

       $nw=$w*$scale;$nw=($nw<1)?1:$nw;

       $nh=$h*$scale;$nh=($nh<1)?1:$nh;



       $d=array(0,0,floor($nw),floor($nh));

       $s=array(0,0,$w,$h);

       }

   else

       {

           if ($crop==3) {$nw=1;$nh=1;}

       elseif ($crop==2) {$nw=1/$format;$nh=1;}

       elseif ($crop==1) {$nw=1;$nh=1/$format;}

       $nw*=$dim;$nw=($nw<1)?1:$nw;

       $nh*=$dim;$nh=($nh<1)?1:$nh;

  

       $s1=$nw/$w;

       $s2=$nh/$h;

       $h1=$nh*$s1;

       $w2=$nw*$s2;



       $s1=($h1<=$nh)?$s1:0;

       $s2=($w2<=$nw)?$s2:0;

       $scale=($s1>$s2)?$s1:$s2;

       $scale=($scale<=0)?1:$scale;



       $d=array(0,0,floor($nw),floor($nh));

       $x1=floor(($w-$d[2]/$scale)/2);$x1=$x1<0?0:$x1;

       $y1=floor(($h-$d[3]/$scale)/2);$y1=$y1<0?0:$y1;

       $s=array($x1,$y1,floor($w-2*$x1),floor($h-2*$y1));

       }



   // input/output

   switch($type1)

       {

       case 'jpg': $imgIn = ImageCreateFromJPEG; break;

       case 'png': $imgIn = ImageCreateFromPNG;  break;

       case 'gif': $imgIn = ImageCreateFromGIF;  break;

       case 'bmp': $imgIn = ImageCreateFromWBMP; break;

       default: return FALSE; break;

       }

   switch($type2)

       {

       case 'jpg': $imgOut = ImageJPEG; break;

       case 'png': $imgOut = ImagePNG;  break;

       case 'gif': $imgOut = ImageGIF;  break;

       case 'bmp': $imgOut = ImageWBMP; break;

       default: return FALSE; break;

       }



   // resample (d-destination, s-source)

   $image1 = $imgIn($photo1);

   if ($methode==0)

       {

       $image2 = ImageCreateTruecolor($d[2],$d[3]);

       ImageCopyResampled($image2, $image1,

 $d[0],$d[1], $s[0],$s[1], $d[2],$d[3], $s[2],$s[3]);

       }

   else    {

       $image2 = ImageCreate($d[2],$d[3]);

       ImageCopyResized($image2, $image1,

$d[0],$d[1], $s[0],$s[1], $d[2],$d[3], $s[2],$s[3]);

       }



   // output

   if ($type2=='jpg')

       {$imgOut($image2,$photo2,85);}

   else    {$imgOut($image2,$photo2);}

   ImageDestroy($image2);

   ImageDestroy($image1);

   }

}

dmitry at dest dot by
07-Mar-2006 10:03


Simple script on change of width and automatic creation of height, and also creation of the signature in the right we string to a corner. (Only for Jpg)



function easyResize($img_sourse, $save_to, $quality, $width, $str) { 

$size = GetImageSize($img_sourse);

    $im_in = ImageCreateFromJPEG($img_sourse);

    

    $new_height = ($width * $size[1]) / $size[0]; // Generate new height for image

    $im_out = imagecreatetruecolor($width, $new_height);

    

    ImageCopyResampled($im_out, $im_in, 0, 0, 0, 0, $width, $new_height, $size[0], $size[1]);

        

    #Find X & Y for note

    $X_var = ImageSX($im_out); 

    $X_var = $X_var - 130;

    $Y_var = ImageSY($im_out); 

    $Y_var = $Y_var - 25;



    #Color

    $white = ImageColorAllocate($im_out, 0, 0, 0);

    

    #Add note(simple: site address)

    ImageString($im_out,2,$X_var,$Y_var,$str,$white);



    ImageJPEG($im_out, $save_to, $quality); // Create image

    ImageDestroy($im_in);

    ImageDestroy($im_out);

}



// $str -  Inscription on the image;

areddan at silverarm dot ie
29-Jan-2006 10:30


$file =$_FILES[userfile];

//name of the input form file upload element is userfile



//$to_file is a full path including filename 

//to where you want the thumnail to be copied to .

//example /usr/www/users/www/images/thumbs/thumb1.jpg



copy($file[tmp_name],$to_file) or die("The file $file[tmp_name] you are trying to upload couldn't be copied to $to_file");



//Extra stuff to put into the output to allow for jpeg / png or gif



//replace line: imagegif($thumb2, $fileout); //write to file with the following



switch($format)

       {

           case 'image/jpeg':

           imagejpeg($thumb2, $fileout,90); //write to file

           break;

           case 'image/gif';

           imagegif($thumb2, $fileout); //write to file

           break;

           case 'image/png':

           imagepng($thumb2, $fileout); //write to file

           break;

       }

areddan at silverarm dot ie
27-Jan-2006 04:40


<?php

// The file

$filein = ''; // File in

$fileout = 'ttt.gif'; // Fileout - optional 



$imagethumbsize_w = 100; // thumbnail size (area cropped in middle of image)

$imagethumbsize_h = 75; // thumbnail size (area cropped in middle of image)

resize_then_crop( $filein,$fileout,$imagethumbsize_w,

$imagethumbsize_h,/*rgb*/"255","255","255");



//Author Alan Reddan Silverarm Solutions

//Date 27/01/2005

//Function that works well with images.

//It takes the image and reduces its size to best fit. i.e If you have an image

//that is 200 X 100 and you want a thumbnail of 75 X 50,

//it first resizes the image to 100 X 50

//and then takes out a portion 75 X 50 from then center of the input image.

//So loads of image information is retained.

//The corollary also holds if your input image is 100 X 200

//it first resizes image to 75 X 150 and then takes out a

//portion 75 X 75 from the centre

// The advantage here is that function decides on whether

//resize is by width or height itself.

//it also decides whether to use the height or the width as the base start point

//in the case that athumbnail is rectangular



function resize_then_crop( $filein,$fileout,

$imagethumbsize_w,$imagethumbsize_h,$red,$green,$blue)

{



// Get new dimensions

list($width, $height) = getimagesize($filein);

$new_width = $width * $percent;

$new_height = $height * $percent;



   if(preg_match("/.jpg/i", "$filein"))

   {

       $format = 'image/jpeg';

   }

   if (preg_match("/.gif/i", "$filein"))

   {

       $format = 'image/gif';

   }

   if(preg_match("/.png/i", "$filein"))

   {

       $format = 'image/png';

   }

   

       switch($format)

       {

           case 'image/jpeg':

           $image = imagecreatefromjpeg($filein);

           break;

           case 'image/gif';

           $image = imagecreatefromgif($filein);

           break;

           case 'image/png':

           $image = imagecreatefrompng($filein);

           break;

       }



$width = $imagethumbsize_w ;

$height = $imagethumbsize_h ;

list($width_orig, $height_orig) = getimagesize($filein);



if ($width_orig < $height_orig) {

  $height = ($imagethumbsize_w / $width_orig) * $height_orig;

} else {

    $width = ($imagethumbsize_h / $height_orig) * $width_orig;

}



if ($width < $imagethumbsize_w)

//if the width is smaller than supplied thumbnail size 

{

$width = $imagethumbsize_w;

$height = ($imagethumbsize_w/ $width_orig) * $height_orig;;

}



if ($height < $imagethumbsize_h)

//if the height is smaller than supplied thumbnail size 

{

$height = $imagethumbsize_h;

$width = ($imagethumbsize_h / $height_orig) * $width_orig;

}



$thumb = imagecreatetruecolor($width , $height);  

$bgcolor = imagecolorallocate($thumb, $red, $green, $blue);   

ImageFilledRectangle($thumb, 0, 0, $width, $height, $bgcolor);

imagealphablending($thumb, true);



imagecopyresampled($thumb, $image, 0, 0, 0, 0,

$width, $height, $width_orig, $height_orig);

$thumb2 = imagecreatetruecolor($imagethumbsize_w , $imagethumbsize_h);

// true color for best quality

$bgcolor = imagecolorallocate($thumb2, $red, $green, $blue);   

ImageFilledRectangle($thumb2, 0, 0,

$imagethumbsize_w , $imagethumbsize_h , $white);

imagealphablending($thumb2, true);



$w1 =($width/2) - ($imagethumbsize_w/2);

$h1 = ($height/2) - ($imagethumbsize_h/2);



imagecopyresampled($thumb2, $thumb, 0,0, $w1, $h1,

$imagethumbsize_w , $imagethumbsize_h ,$imagethumbsize_w, $imagethumbsize_h);



// Output

//header('Content-type: image/gif');

//imagegif($thumb); //output to browser first image when testing



if ($fileout !="")imagegif($thumb2, $fileout); //write to file

header('Content-type: image/gif');

imagegif($thumb2); //output to browser

}

?>

com.hotmail@backglancer
08-Jan-2006 02:32


wrote this for a game I was helping develop:



Auto Tile Maker -- takes the image and cuts it in several smaller pieces, deleting the original... i mean.. this is just for those of you who are lazy, coz the script is simple..

modify at will.



<?

// $newfile is the full address of your newly uploaded file

// $floc = is the location of that file ending with /

// $t is the $_FILES['blah'] of your uploaded file.

// whatever... you guys understand enough to modify this code



$size = getimagesize($newfile);

list($w, $h) = $size;



if ($h > 20 || $w > 20) {

    $type = array_pop($size);

    switch ($type) {

        case 'image/jpeg' : $src_image = imagecreatefromjpeg($newfile); break;

        // insert more cases here :) i'm lazy too

        default : echo 'not an image!'; return;

    }



    $i = 0;

    for ($y = 0; $y < $h; $y += 20) {

    for ($x = 0; $x < $w; $x += 20) {

        $i++; // new file names will be like 1monkey.gif 2monkey.gif etc..

        $new_image = imagecreatetruecolor(20, 20);



        imagecopyresampled ($new_image, $src_image,

            0, 0,

            $x, $y,

            20, 20,

            20, 20

            );

        imagegif($new_image, $floc.$i.$t['name']);

        imagedestroy($new_image);



    } // x

    } // y

    unlink($newfile);

}

?>

smrtak at 4um dot cz
07-Dec-2005 03:48


class cobrazek 

    { 

        function resizeMaxJpeg($file,$mx,$my,$q=85) 

        { 

            $dst = cobrazek::resizeMax(imagecreatefromjpeg($file),$mx,$my); 

            if(!$dst) 

                return false; 

            if(!imagejpeg($dst,$file,$q)) 

                return false; 

            return true; 

        } 

        function resizeMax($src,$mx,$my) 

        { 

            //zjisti velikost 

            $sx = imagesx($src); 

            $sy = imagesy($src); 

            //spocitej cilovou velikost 

            $v = min(min($mx,$sx)/$sx,min($my,$sy)/$sy); 

            $dx = $v*$sx; 

            $dy = $v*$sy; 

            $dst = imagecreatetruecolor($dx,$dy); 

            //resample 

            imagecopyresampled ($dst,$src,0,0,0,0,$dx,$dy,$sx,$sy); 

            //vystup 

            return $dst; 

        } 

    }

pike-php at kw dot nl
15-Nov-2005 06:21


If you have a bug that imagecopyresampled is completely ignoring srcX and srcY (a known and closed bug - http://bugs.php.net/bug.php?id=12780)  you can ofcourse apply two operations to do the same. E.g., instead of saying



ImageCopyResampled($dst_img, $src_img, 0, 0, $srcX, $srcY, $dstW, $dstH, $srcW, $srcH);



you can say



ImageCopyResampled($tmp_img, $src_img, -$srcX, -$srcY, "BUG","BUG", $orgW, $orgH, $orgW, $orgH);

ImageCopyResampled($dst_img, $tmp_img, 0, 0, "BUG","BUG", $dstW, $dstH, $srcW, $srcH);



which has the same effect but is twice as slow and blurry. you may replace "BUG","BUG" with anything you like without sideeffects :)



$2c,

*pike

George_A
08-Nov-2005 06:49


For the best image quality...

How to get new proportional size of the image if the desible size of source image is approximatly equal to needed size. If needed size differs from source size on less than the user factor then transformation isn`t apply.



/**********************************************/

function imageCopyResize($image, $xSize, $ySize, $needed_user_factor, $new_image_path = "")

{

 //example: neded_user_factor = 0.2

 if($xSize == 0 || $ySize == 0)

    return array("At the leat one pair of size is 0",0,0);



 $size = getImageSize($image);

 $width = $size[0];

 $height = $size[1];

 $x_ratio = $xSize / $size[0]; 

 $y_ratio = $ySize / $size[1]; 

 if($x_ratio > $y_ratio)    $res_ratio = $y_ratio;

 else $res_ratio = $x_ratio;

 if(abs($res_ratio - 1) > $needed_user_factor)

    {

     $width = ceil($width * $res_ratio);

     $height = ceil($height * $res_ratio);

    }

 $fileinfo = pathinfo($image);

 $file_type = strtolower($fileinfo["extension"]);

 if($file_type == "jpg" || $file_type == "jpeg")

    $src = ImageCreateFromJpeg($image);

 else if($file_type == "gif")

    $src = ImageCreateFromGif($image);

 else if($file_type == "png")

    $src = ImageCreateFromPNG($image);

 else if($file_type == "bmp")    

    $src = ImageCreateFromBmp($image);    //Thanks Previous Coder

 else

   return array("Unknown image format: ".$file_type, 0, 0);   

 $output_path = ($new_image_path == "")?$image:$new_image_path;

 $dst = ImageCreateTrueColor($width, $height);

 ImageCopyResized($dst, $src, 0,0,0,0,$width, $height, $size[0], $size[1]);

 if($file_type == "jpg" || $file_type == "jpeg")

    ImageJpeg($dst, $output_path, 100);

 else if($file_type == "gif" || $file_type == "bmp")

     ImageGif($dst, $output_path);

 else if($file_type == "png")

    ImagePNG($dst, $output_path);



 ImageDestroy($src);

 ImageDestroy($dst);

 return array("", $width, $height);

}

/**********************************************/

erik at phpcastle dot com
05-Nov-2005 06:21


I've changed the script from info at lontronics dot nl a little bit so the thumbnail is not cutted off when this is not necessary.



<?php

// Resize function



// $pictype is optional. When empty the image will not be cutted off

function resize($filename, $dest, $width, $height, $pictype = "")

{

  $format = strtolower(substr(strrchr($filename,"."),1));

  switch($format)

  {

    case 'gif' :

    $type ="gif";

    $img = imagecreatefromgif($filename);

    break;

    case 'png' :

    $type ="png";

    $img = imagecreatefrompng($filename);

    break;

    case 'jpg' :

    $type ="jpg";

    $img = imagecreatefromjpeg($filename);

    break;

    case 'jpeg' :

    $type ="jpg";

    $img = imagecreatefromjpeg($filename);

    break;

    default :

    die ("ERROR; UNSUPPORTED IMAGE TYPE");

    break;

  }



  list($org_width, $org_height) = getimagesize($filename);

  $xoffset = 0;

  $yoffset = 0;

  if ($pictype == "thumb") // To minimize destortion

  {

    if ($org_width / $width > $org_height/ $height)

    {

      $xtmp = $org_width;

      $xratio = 1-((($org_width/$org_height)-($width/$height))/2);

      $org_width = $org_width * $xratio;

      $xoffset = ($xtmp - $org_width)/2;

    }

    elseif ($org_height/ $height > $org_width / $width)

    {

      $ytmp = $org_height;

      $yratio = 1-((($width/$height)-($org_width/$org_height))/2);

      $org_height = $org_height * $yratio;

      $yoffset = ($ytmp - $org_height)/2;

    }

  //Added this else part -------------

  } else {    

      $xtmp = $org_width/$width;

      $new_width = $width;

      $new_height = $org_height/$xtmp;

      if ($new_height > $height){

        $ytmp = $org_height/$height;

        $new_height = $height;

        $new_width = $org_width/$ytmp;

      }

      $width = round($new_width);

      $height = round($new_height);

  }

  



  $img_n=imagecreatetruecolor ($width, $height);

  imagecopyresampled($img_n, $img, 0, 0, $xoffset, $yoffset, $width, $height, $org_width, $org_height);



  if($type=="gif")

  {

    imagegif($img_n, $dest);

  }

  elseif($type=="jpg")

  {

    imagejpeg($img_n, $dest);

  }

  elseif($type=="png")

  {

    imagepng($img_n, $dest);

  }

  elseif($type=="bmp")

  {

    imagewbmp($img_n, $dest);

  }

  Return true;

}

?>

info at lontronics dot nl
28-Oct-2005 06:08


For an internet photoalbum I was looking for a script which I could simply drop in a directory with images and which would do the rest.

Therefor I am using the following resize script now. I have made the little thumb-part because I want to have all the same size thumbnails, but with as less as possible distortion. Therefor, images with other dimensions are resized, but also cut off a little.



Als $pictype = thumb, the extra dimension calculations are used

$width and $height are the new dimensions of $filename, the image

$dest is the directory where the new image must be copied in.



The script:



// Resize function

function resize($filename, $dest, $width, $height, $pictype)

{

    $format = strtolower(substr(strrchr($filename,"."),1));

    switch($format)

    {

        case 'gif' :

            $type ="gif";

            $img = imagecreatefromgif($filename);

            break;

        case 'png' :

            $type ="png";

            $img = imagecreatefrompng($filename);

            break;

        case 'jpg' :

            $type ="jpg";

            $img = imagecreatefromjpeg($filename);

            break;

        case 'jpeg' :

            $type ="jpg";

            $img = imagecreatefromjpeg($filename);

            break;

        default : 

            die ("ERROR; UNSUPPORTED IMAGE TYPE");

            break;

    }

    

    list($org_width, $org_height) = getimagesize($filename);

    $xoffset = 0;

    $yoffset = 0;

    if ($pictype == "thumb") // To minimize destortion

    {

        if ($org_width / $width > $org_height/ $height)

        {

            $xtmp = $org_width;

            $xratio = 1-((($org_width/$org_height)-($width/$height))/2);

            $org_width = $org_width * $xratio;

            $xoffset = ($xtmp - $org_width)/2;

        }

        elseif ($org_height/ $height > $org_width / $width)

        {

            $ytmp = $org_height;

            $yratio = 1-((($width/$height)-($org_width/$org_height))/2);

            $org_height = $org_height * $yratio;

            $yoffset = ($ytmp - $org_height)/2;

        }

    }



    $img_n=imagecreatetruecolor ($width, $height);    

    imagecopyresampled($img_n, $img, 0, 0, $xoffset, $yoffset, $width, $height, $org_width, $org_height);



    if($type=="gif")

    {

        imagegif($img_n, $dest);

    }

    elseif($type=="jpg")

    {

        imagejpeg($img_n, $dest);

    }

    elseif($type=="png")

    {

        imagepng($img_n, $dest);

    }

    elseif($type=="bmp")

    {

        imagewbmp($img_n, $dest);

    }

    Return true;

}

Nicolas dot Grasset at notup2u dot net
21-Oct-2005 05:33


If you are looking for a function that can resample your photos to a given size, no matter its original size and/or ratio, here it is. And to make more fun (beacause life has to be fun), you can even chose a border size for the picture!



$position can either be topleft, topright, bottomleft, bottomright or center.



<?php



function imagecopyresampledselection($filename, $desired_width, $desired_height, $bordersize, $position)

{    

    // Get new dimensions

    list($width, $height) = getimagesize($filename);

    if($desired_width/$desired_height > $width/$height):

        $new_width = $desired_width;

        $new_height = $height * ($desired_width / $width);

    else:

        $new_width = $width * ($desired_height / $height);

        $new_height = $desired_height;

    endif;

    

    // Resize

    $image_p = imagecreatetruecolor($new_width, $new_height);

    $image_f = imagecreatetruecolor($desired_width, $desired_height);

    $image = imagecreatefromjpeg($filename);

    imagecopyresampled($image_p, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);

    

    // Adjust position

    switch($position)

    {

        case("topleft"):

            $x = $bordersize;

            $y = $bordersize;

            break;

            

        case("topright"):

            $x = $new_width - $desired_width + $bordersize;

            $y = $bordersize;

            break;

        

        case("bottomleft"):

            $x = $bordersize;

            $y = $new_height - $desired_height + $bordersize;

            break;

        

        case("bottomright"):

            $x = $new_width - $desired_width + $bordersize;

            $y = $new_height - $desired_height + $bordersize;

            break;

        

        case("center"):

            $x = ($new_width - $desired_width) / 2 + $bordersize;

            $y = ($new_height - $desired_height) / 2 + $bordersize;

            break;

    }

    

    // Resample with 1px border

    imagecopyresampled($image_f, $image_p, $bordersize, $bordersize, $x, $y,     $desired_width    - 2 * $bordersize, 

                                                                                $desired_height    - 2 * $bordersize, 

                                                                                $desired_width    - 2 * $bordersize, 

                                                                                $desired_height    - 2 * $bordersize);

    

    return $image_f;

}



$image_f = imagecopyresampledselection('test.jpg', 571, 319, 1, "center");

header('Content-type: image/jpeg');

imagejpeg($image_f, null, 100);



?> 



To see a result, just browse http://www.notup2u.net/v8



Nicolas Grasset

12-Aug-2005 08:19


Here is my own custom utility which I call "Thumbnailer" (I know it is cheesy).

It's rather short, and it will take JPEG (you can change that easily), and

format it to a specified output width and height as a PNG

(or whatever else you choose):

<?php

//Dimensions

$outWidth=100; $outHeight=75;

//Do it

$imgSrc=imagecreatefromjpeg("[source]");

$srcWidth=imagesx($imgSrc);

$srcHeight=imagesy($imgSrc);

//Make thumbnails

$imgOut=imagecreatetruecolor($outWidth,$outHeight);

imagerectangle($imgOut,0,0,$outWidth,$outHeight,

 imagecolorallocate($imgOut,0,0,0));

//Copy them proportionatly

$dx=0; $dy=0; $dw=$outWidth; $dh=$outHeight;

if ($outWidth*$srcHeight!=$outHeight*$srcWidth) { //Non-proportional, cut-off

 //Which dimensions is larger

 if ($srcWidth>$srcHeight) { //Empty space on top and bottom

  $dw=$outWidth;

  $dh=($dw*$srcHeight)/$srcWidth;

  $dy=($outHeight-$dh)/2;

 }

 else { //Empty space on left and right

  $dh=$outHeight;

  $dw=($dh*$srcWidth)/$srcHeight;

  $dx=($outWidth-$dw)/2;

 }

}

imagecopyresampled($imgOut,$imgSrc,$dx,$dy,0,0,

 $dw,$dh,$srcWidth,$srcHeight); //imagecopyresized for lower quality

//Create the thumbnail and destroy everything else

imagepng($imgOut,"[out]");

echo "Image created successfully: $outWidth x $outHeight, ".round(filesize("[source]")/1024)." KB<br>";

imagedestroy($imgSrc);

imagedestroy($imgOut);

?>

I just use this as a loop to create thumbnails for a series of ordered images.

phpman at paodj dot net
20-Jul-2005 06:27


<?php



function img_resize($path,$w=0,$h=0,$quality=100,$save=''){



  $image_data=@getimagesize($path);



  $image_type=$image_data[2];

  $gd_ext=array('','jpg','gif');

  if($image_type!=1&&$image_type!=2) return false;

  if($save=='') header('Content-type: '.$image_data['mime']); else $save=eregi_replace('%ext',$gd_ext[$image_type],$save);



  if($w!=0){

    $rapporto=$image_data[0]/$w;

    if($h!=0){

      if($image_data[1]/$rapporto>$h) $rapporto=$image_data[1]/$h;

    }

  }elseif($h!=0){

    $tmp_h=$image_data[1]/$h;

  }else{

    return false;

  }



  $thumb_w=$image_data[0]/$rapporto;

  $thumb_h=$image_data[1]/$rapporto;



  if($image_type==1) $img_src=@imagecreatefromgif($path);

  elseif($image_type==2) $img_src=@imagecreatefromjpeg($path);



  $img_thumb=@imagecreatetruecolor($thumb_w,$thumb_h);

  $result=@imagecopyresampled($img_thumb,$img_src,

0,0,0,0,$thumb_w,$thumb_h,$image_data[0],$image_data[1]);

  if(!$img_src||!$img_thumb||!$result) return false;



  if($image_type==1) $result=@imagegif($img_thumb,$save);

  elseif($image_type==2) $result=@imagejpeg($img_thumb,$save,$quality);



  return $result;

}



?>



This script resize images. It can also make thumbs. It use the resample of images for hight quality result.



It can show the result or save it (if $save isn't null).

It respect the width and/or the height of image.

It can replace the destination file extestion dinamically (filename.%ext)

Support gif & jpg.



Return false if something goes wrong.

05-Jul-2005 08:46


It should be noted that the imagecopyresampled() function is much more blurry than Photoshop CS's default bicubic funtion. And looks similar to a blury version of Photoshop's bilinear function. The documentation fails to note which algorithm is used in resampling.

Pie pie
26-May-2005 08:21


Confirming on what fluffle said, and to say his code will also crop and resize an image what is smaller than 100x100 pixels if you want. This is important because it means your images no matter how you decide to rezise them, will maintain their aspect ratios and with a minimum amount of image loss.



    //Get file type

    $mime = $orig_image_mimetype;

    $type = substr($mime, strpos($mime,'/')+1);

    switch($type) {

        case 'jpeg':

        case 'pjpeg':

            $big = imagecreatefromjpeg($file);

            break;

        case 'png':

        case 'x-png':

            $big = imagecreatefrompng($file);

             break;

        case 'gif':

            $big = imagecreatefromgif($file);

            break;

        default:

            return FALSE;

            break;

    }



The above code is what I use to support multiple file type resizing. I then use the same thing again when it's time to output the image using $result = imagejpeg($thumb,'',80), imagepng($thumb), and imagegif($thumb).

fluffle <at> gmail <dot> com
21-May-2005 04:35


Just to clarify that src_w and src_h do not necessarily need to be the source image width and height, as they specify the size of the rectangle cropped from the source picture, with its top left corner situated at (src_x, src_y).



For example, the code below crops a jpeg image to be square, with the square situated in the centre of the original image, and then resizes it to a 100x100 thumbnail.



list($ow, $oh) = getimagesize($image_filename);

$big = imagecreatefromjpeg($image_filename);

$thumb = imagecreatetruecolor(100,100);

if ($ow > $oh) {

    $off_w = ($ow-$oh)/2;

    $off_h = 0;

    $ow = $oh;

} elseif ($oh > $ow) {

    $off_w = 0;

    $off_h = ($oh-$ow)/2;

    $oh = $ow;

} else {

    $off_w = 0;

    $off_h = 0;

}

imagecopyresampled($thumb, $big, 0, 0, $off_w, $off_h, 100, 100, $ow, $oh);

carnivorous_winds_fr AT yahoo DOT fr
19-May-2005 01:47


I tried this code from a previous post.



<?

...

         $t_im = imageCreateTrueColor($t_wd,$t_ht);

         imageAntiAlias($t_im,true);

         imagealphablending($t_im, false);

         imagesavealpha($t_im,true);

         $transparent = imagecolorallocatealpha($t_im, 255, 255, 255, 0);

         for($x=0;$x<$t_wd;$x++) {

           for($y=0;$y<$t_ht;$y++) {

             imageSetPixel( $t_im, $x, $y, $transparent );

           }

         }

         imageCopyResampled($t_im, $o_im, 0, 0, 0, 0, $t_wd, $t_ht, $o_wd, $o_ht);

         imagePNG($t_im, $image_name);

...

?>



It seems that it is not working correctly. In my test the source picture in ImageCopyResampled() is smaller than the destination picture $t_im, the remaining part is white !



I changed transparent alpha channel to 127, and I tried to replace loops with imagefilledrectangle().



It works fine and these resource greedy loops are removed.



Here is the code with my change.



<?

...

         $t_im = imageCreateTrueColor($t_wd,$t_ht);

         imageAntiAlias($t_im,true);

         imagealphablending($t_im, false);

         imagesavealpha($t_im,true);

         $transparent = imagecolorallocatealpha($t_im, 255, 255, 255, 127);

         imagefilledrectangle($t_img, 0, 0, $t_wd, $t_ht, $transparent);

         imageCopyResampled($t_im, $o_im, 0, 0, 0, 0, $t_wd, $t_ht, $o_wd, $o_ht);

         imagePNG($t_im, $image_name);

...

?>

del at kartoon dot net
05-May-2005 04:38


This snippet allows you to grab a thumbnail from the center of a large image.  This was used for a client photo gallery for art to give a teaser of the image to come (only a small portion).  You could get dynamic with this value.  I also put in a scaling factor in case you want to scale down first before chopping.



<?php

// The file

$filename = 'moon.jpg';

$percent = 1.0; // if you want to scale down first

$imagethumbsize = 200; // thumbnail size (area cropped in middle of image)

// Content type

header('Content-type: image/jpeg');



// Get new dimensions

list($width, $height) = getimagesize($filename);

$new_width = $width * $percent;

$new_height = $height * $percent;



// Resample

$image_p = imagecreatetruecolor($imagethumbsize , $imagethumbsize);  // true color for best quality

$image = imagecreatefromjpeg($filename);



// basically take this line and put in your versin the -($new_width/2) + ($imagethumbsize/2) & -($new_height/2) + ($imagethumbsize/2) for

// the 2/3 position in the 3 and 4 place for imagecopyresampled

// -($new_width/2) + ($imagethumbsize/2)

// AND

// -($new_height/2) + ($imagethumbsize/2)

// are the trick

imagecopyresampled($image_p, $image, -($new_width/2) + ($imagethumbsize/2), -($new_height/2) + ($imagethumbsize/2), 0, 0, $new_width , $new_width , $width, $height);



// Output



imagejpeg($image_p, null, 100);

?>

djneoform at gmail dot com
04-Mar-2005 10:21


Here's a function i made that will force a given set of constraints on an image (usrfull if you want to make thumbnails that are all the same size) while keeping aspect ratio.



It resizes, then crops the extra off the top or bottom.



function forceConstraints($srcFile, $srcType, $dstType, $dstWidth, $dstHeight, $dstPath)

{

    if ($srcType == "image/jpeg")

        $handle = @imagecreatefromjpeg($srcFile);

    else if ($srcType == "image/png")

        $handle = @imagecreatefrompng($srcFile);

    else if ($srcType == "image/gif")

        $handle = @imagecreatefromgif($srcFile);

    else

        return false;



    if (!$handle)

        return false;



    $srcWidth  = @imagesx($handle);

    $srcHeight = @imagesy($handle);



    if ($srcWidth >= $dstWidth && $srcHeight >= $dstHeight)

    {

        $newHandle = @imagecreatetruecolor($dstWidth, $dstHeight);

        if (!$newHandle)

            return false;



        if($srcHeight < $srcWidth)

        {

            $ratio = (double)($srcHeight / $dstHeight);



            $cpyWidth = round($dstWidth * $ratio);

            if ($cpyWidth > $srcWidth)

            {

                $ratio = (double)($srcWidth / $dstWidth);

                $cpyWidth = $srcWidth;

                $cpyHeight = round($dstHeight * $ratio);

                $xOffset = 0;

                $yOffset = round(($srcHeight - $cpyHeight) / 2);

            } else {

                $cpyHeight = $srcHeight;

                $xOffset = round(($srcWidth - $cpyWidth) / 2);

                $yOffset = 0;

            }



        } else {

            $ratio = (double)($srcWidth / $dstWidth);



            $cpyHeight = round($dstHeight * $ratio);

            if ($cpyHeight > $srcHeight)

            {

                $ratio = (double)($srcHeight / $dstHeight);

                $cpyHeight = $srcHeight;

                $cpyWidth = round($dstWidth * $ratio);

                $xOffset = round(($srcWidth - $cpyWidth) / 2);

                $yOffset = 0;

            } else {

                $cpyWidth = $srcWidth;

                $xOffset = 0;

                $yOffset = round(($srcHeight - $cpyHeight) / 2);

            }

        }



        if (!@imagecopyresampled($newHandle, $handle, 0, 0, $xOffset, $yOffset, $dstWidth, $dstHeight, $cpyWidth, $cpyHeight))

            return false;

        @imagedestroy($handle);



        if ($dstType == "png")

            @imagepng($newHandle, $dstPath.".png");

        else if ($dstType == "jpg")

            @imagejpeg($newHandle, $dstPath.".jpg", 90);

        else if ($dstType == "gif")

            @imagegif($newHandle, $dstPath.".gif");

        else

            return false;

        @imagedestroy($newHandle);

        return true;



    } else {

        return "Sorry, that image is too small. The image must be at least ".$dstWidth."x".$dstHeight." pixels in size.";

    }

}

afrowuk at tiscali dot co dot uk
02-Jan-2005 11:17


This simple function resizes a JPG image file giving just a maximum width, and resizes keeping the aspect ratio. This is useful if you have to resize a JPG image that must fit the width of i.e. a div element, but doesn't have to have a maximum height.

<?

function resizeJPG($jpgFile, $width) {



    // Get new dimensions

    list($width_orig, $height_orig) = getimagesize($jpgFile);

    $height = (int) (($width / $width_orig) * $height_orig);



    // Resample

    $image_p = imagecreatetruecolor($width, $height);

    $image = imagecreatefromjpeg($jpgFile);

    imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig);



    // Output

    imagejpeg($image_p, $jpgFile, 100);



}

?>



-Stu

stemplar444 at yahoo dot com
12-Aug-2004 01:57


Two comments regarding imageCopyResampleBicubic() published here. 



Quality:

More grainy than imagecopyresampled(). Not very good for bigger destination images, I think.



Speed:

In my tests, it was only faster if destination size was smaller than ~200x200 pixel. The function becomes slower and slower the bigger the destination image gets. In contrast, imagecopyresampled() finished at the same speed, no matter how big the destination was. My source image resoloution ~ 1500x2000 pixel.

ron at korving dot demon dot nl
08-Aug-2004 05:25


This Bicubic resample algorithm is based on the one Scott posted earlier, only this one is about 50% faster for truecolor images and about 10% faster for palette images.



<?



function imageCopyResampleBicubic($dst_img, $src_img, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h)

{

  $scaleX = ($src_w - 1) / $dst_w;

  $scaleY = ($src_h - 1) / $dst_h;



  $scaleX2 = $scaleX / 2.0;

  $scaleY2 = $scaleY / 2.0;



  $tc = imageistruecolor($src_img);



  for ($y = $src_y; $y < $src_y + $dst_h; $y++)

  {

    $sY   = $y * $scaleY;

    $siY  = (int) $sY;

    $siY2 = (int) $sY + $scaleY2;



    for ($x = $src_x; $x < $src_x + $dst_w; $x++)

    {

      $sX   = $x * $scaleX;

      $siX  = (int) $sX;

      $siX2 = (int) $sX + $scaleX2;



      if ($tc)

      {

        $c1 = imagecolorat($src_img, $siX, $siY2);

        $c2 = imagecolorat($src_img, $siX, $siY);

        $c3 = imagecolorat($src_img, $siX2, $siY2);

        $c4 = imagecolorat($src_img, $siX2, $siY);



        $r = (($c1 + $c2 + $c3 + $c4) >> 2) & 0xFF0000;

        $g = ((($c1 & 0xFF00) + ($c2 & 0xFF00) + ($c3 & 0xFF00) + ($c4 & 0xFF00)) >> 2) & 0xFF00;

        $b = ((($c1 & 0xFF)   + ($c2 & 0xFF)   + ($c3 & 0xFF)   + ($c4 & 0xFF))   >> 2);



        imagesetpixel($dst_img, $dst_x + $x - $src_x, $dst_y + $y - $src_y, $r+$g+$b);

      }

      else

      {

        $c1 = imagecolorsforindex($src_img, imagecolorat($src_img, $siX, $siY2));

        $c2 = imagecolorsforindex($src_img, imagecolorat($src_img, $siX, $siY));

        $c3 = imagecolorsforindex($src_img, imagecolorat($src_img, $siX2, $siY2));

        $c4 = imagecolorsforindex($src_img, imagecolorat($src_img, $siX2, $siY));



        $r = ($c1['red']   + $c2['red']   + $c3['red']   + $c4['red']  ) << 14;

        $g = ($c1['green'] + $c2['green'] + $c3['green'] + $c4['green']) << 6;

        $b = ($c1['blue']  + $c2['blue']  + $c3['blue']  + $c4['blue'] ) >> 2;



        imagesetpixel($dst_img, $dst_x + $x - $src_x, $dst_y + $y - $src_y, $r+$g+$b);

      }

    }

  }

}



?>

16-Jul-2004 08:09


In add to all the posts that describes how to create thumbnails:



If you are trying to resample a png image with its transparency you need to do this workaround:



<?

...

          $t_im = imageCreateTrueColor($t_wd,$t_ht);

          imageAntiAlias($t_im,true);

          imagealphablending($t_im, false);

          imagesavealpha($t_im,true);

          $transparent = imagecolorallocatealpha($t_im, 255, 255, 255, 0);

          for($x=0;$x<$t_wd;$x++) {

            for($y=0;$y<$t_ht;$y++) {

              imageSetPixel( $t_im, $x, $y, $transparent );

            }

          }

          imageCopyResampled($t_im, $o_im, 0, 0, 0, 0, $t_wd, $t_ht, $o_wd, $o_ht);

          imagePNG($t_im, $image_name);

...

?>



The alphablending must be off so the imagesavealpha can be true.



The double FORs is need to fix the problem with imagefill function that not support colors with alpha setted.



It is TO SLOWLIER than imagefill, but do a nice work with static images.



Take a look and enjoy the nice result.



(this workaround needs the gd2 library)



[s]

Pigmeu

m.kumar [at] gmx.at
31-Aug-2001 12:10


For those who think that resampling loads the server too badly, have a look at this fine article over at zend:





http://www.zend.com/zend/art/scriptcaching.php





it describes how to create static html from scripts, however, this technique is pretty easily applicable to images.





I've written a short script to outline how to adapt my above mentioned article for caching of thumbnails. see:


http://tzu.nme.at/php/cache.phps

add a note

imagecopyresampled

说明

范例

参见