[Resolved] dynamic resizing of uploaded imgs

[cgraz]

I know this has been asked a MILLION times, but I'm still a little confused. I've got to get this done today or tomorrow for a client, and everytime I try something new, I always end up messing everything else up (which would suck since I'm leaving for a trip after this gets up).

Anyways, I've got the upload working, I just need to make sure that the image that gets uploaded is 640 x 480 (no need to save 2 seperate files for thumbnail and large, just one image at 640 x 480). Here's my code (wrote this a while back, so not the best code, but it works 😃)

<?

if(($picture) && (file_exists("$vehicles_dir/$picture_name"))) {
    $picture_exists = "y";
    echo "Picture 1 has the same filename as a picture already on the server. \n";
    echo "To fix this problem, give Picture 1 a new name that does not exist on the server and <a href=javascript:history.back() class=\"main\">try again</a>. <b>No images have been uploaded.</b>\n";
    exit;
} else {
    $picture_exists = "n";
}


if(($picture2) && (file_exists("$vehicles_dir/$picture2_name"))) {
    $picture2_exists = "y";
    echo "Picture 2 has the same filename as a picture already on the server. \n";
    echo "To fix this problem, give Picture 2 a new name that does not exist on the server and <a href=javascript:history.back() class=\"main\">try again</a>. <b>No images have been uploaded.</b>\n";
    exit;
} else {
    $picture2_exists = "n";
}

if(($picture3) && (file_exists("$vehicles_dir/$picture3_name"))) {
    $picture3_exists = "y";
    echo "Picture 3 has the same filename as a picture already on the server. \n";
    echo "To fix this problem, give Picture 3 a new name that does not exist on the server and <a href=javascript:history.back() class=\"main\">try again</a>. <b>No images have been uploaded.</b>\n";
    exit;
} else {
    $picture3_exists = "n";
}

if(($picture4) && (file_exists("$vehicles_dir/$picture4_name"))) {
    $picture4_exists = "y";
    echo "Picture 4 has the same filename as a picture already on the server. \n";
    echo "To fix this problem, give Picture 4 a new name that does not exist on the server and <a href=javascript:history.back() class=\"main\">try again</a>. <b>No images have been uploaded.</b>\n";
    exit;
} else {
    $picture4_exists = "n";
}

if(($picture5) && (file_exists("$vehicles_dir/$picture5_name"))) {
    $picture5_exists = "y";
    echo "Picture 5 has the same filename as a picture already on the server. \n";
    echo "To fix this problem, give Picture 5 a new name that does not exist on the server and <a href=javascript:history.back() class=\"main\">try again</a>. <b>No images have been uploaded.</b>\n";
    exit;
} else {
    $picture5_exists = "n";
}

unset($_POST['submit']);
unset($_POST['action']);


$_POST['price'] = str_replace(",","",$_POST['price']);
$_POST['price'] = str_replace("$","",$_POST['price']);

// REPLACE COMMAS FROM MILAGE

$_POST['mileage'] = str_replace(",","",$_POST['mileage']);


if (!$picture) {
	$_POST["picture"] = "noimage.gif";
} else {
        $_POST["picture"] = $picture_name;
}

$_POST["picture2"] = $picture2_name;
$_POST["picture3"] = $picture3_name;
$_POST["picture4"] = $picture4_name;
$_POST["picture5"] = $picture5_name;

// insert into database

foreach($_POST as $key => $value) {
   $keys[] = $key;
}

$query = "INSERT INTO $table (" . implode(",", $keys) . ")";
$query .= " VALUES('" . implode("','", $_POST) . "')";

$result = mysql_query($query) or die(mysql_error());

if (($picture) && ($picture_exists == 'n')) {
copy($picture, "$vehicles_dir/$picture_name");
}


if (($picture2) && ($picture2_exists == 'n')) {
copy($picture2, "$vehicles_dir/$picture2_name");
}


if (($picture3) && ($picture3_exists == 'n')) {
copy($picture3, "$vehicles_dir/$picture3_name");
}


if (($picture4) && ($picture4_exists == 'n')) {
copy($picture4, "$vehicles_dir/$picture4_name");
}


if (($picture5) && ($picture5_exists == 'n')) {
copy($picture5, "$vehicles_dir/$picture5_name");
}


?>

<center>Vehicle Posted Successfully.<br><br>

Click <a href="index.php" class="main">here</a> to return to your administrative home page.

</center>

I posted all the code so you can follow what's going on, but seriously, any help (explanation) or code would be great....I'm just really worried about screwing up how this whole thing works.

Cgraz

[ScubaKing22]

If all you need is the size, have a look at getimagesize().

Hope this helps!

[cgraz]

well i know how to check the image size, i just want to actually resize that image to 640 x 480 if it's larger than 640 x 480. I have no idea how to resize an image and have been searching through php.net but i'm pretty confused.

I found a function at http://www.php.net/ImageCopyResized that seems like it might work for what I want to do. Can I just use this function how it is, and if so, how do I call the function (i'm not sure what all those parameters are).

Thanks

<?
ImageCopyResample(.....);
ImageJPEG(......);

function ImageCopyResample(&$dst_img, &$src_img, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h) {
   global $resample; //submittet by querystring
   $pxls = intval($src_w / $dst_w)-1;
   if (($resample!="bicubic" && $pxls>=2) or $resample=="bilinear"){ //slow but better quality
             ImagePaletteCopy ($dst_img, $src_img);
             $rX = $src_w / $dst_w;
             $rY = $src_h / $dst_h;
             $nY = 0;
             for ($y=$src_y; $y<$dst_h; $y++) {
               $oY = $nY;
               $nY = intval(($y + 1) * $rY+.5);
               $nX = 0;
               for ($x=$src_x; $x<$dst_w; $x++) {
                 $r = $g = $b = $a = 0;
                 $oX = $nX;
                 $nX = intval(($x + 1) * $rX+.5);
                 $c = ImageColorsForIndex ($src_img, ImageColorAt ($src_img, $nX, $nY));
                 $r += $c['red']; $g += $c['green']; $b += $c['blue']; $a++;
                 $c = ImageColorsForIndex ($src_img, ImageColorAt ($src_img, $nX-$pxls, $nY-$pxls));
                 $r += $c['red']; $g += $c['green']; $b += $c['blue']; $a++;
                 //you can add more pixels here! eg "$nX, $nY-$pxls" or "$nX-$pxls, $nY"
                 ImageSetPixel ($dst_img, ($x+$dst_x-$src_x), ($y+$dst_y-$src_y), ImageColorClosest ($dst_img, $r/$a, $g/$a, $b/$a));
               }
             }
         return true;
   } elseif ($resample=="bicubic"){ //very slow but better quality
             ImagePaletteCopy ($dst_img, $src_img);
             $rX = $src_w / $dst_w;
             $rY = $src_h / $dst_h;
             $nY = 0;
             for ($y=$src_y; $y<$dst_h; $y++) {
               $oY = $nY;
               $nY = intval(($y + 1) * $rY+.5);
               $nX = 0;
               for ($x=$src_x; $x<$dst_w; $x++) {
                 $r = $g = $b = $a = 0;
                 $oX = $nX;
                 $nX = intval(($x + 1) * $rX+.5);
                 for ($i=$nY; --$i>=$oY;) {
                   for ($j=$nX; --$j>=$oX;) {
                     $c = ImageColorsForIndex ($src_img, ImageColorAt ($src_img, $j, $i));
                     $r += $c['red'];
                     $g += $c['green'];
                     $b += $c['blue'];
                     $a++;
                   }
                 }
                 ImageSetPixel ($dst_img, ($x+$dst_x-$src_x), ($y+$dst_y-$src_y), ImageColorClosest ($dst_img, $r/$a, $g/$a, $b/$a));
               }
             }
         return true;
   } else { //very fast!
   $dst_w++; $dst_h++; //->no black border
     return imagecopyresized($dst_img, $src_img, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h);
   }
}
?> 

Cgraz

[Weedpacket]

Since you're resizing the whole image, the four offsets (dst|src)_(x|y) are all zero (i.e., the very top-left corner of both the source and destination images), and the src width and height are the width and height of the source image, and the dst width and height are the desired width and height of the destination image.

PS: You might get better-quality results with imagecopyresampled.

[cgraz]

Weed:

Thank you. That really cleared up a lot of confusion on what all thos parameters were!

I tried using imagecopyresampled() but I'm getting Call to undefined function: imagecopyresampled() error.

So I'm just using imagecopyresized right now, but I'm not exactly sure why I keep getting this error that says

Warning: imagecopyresized(): supplied argument is not a valid Image resource in ....

I tried using $_FILES["picture"], $picture, and a few other variations and I'm not sure what it is I need to do to have it recognize the image resource. Here's the code I wrote up to get it all working before integrating with my previous code:

<?

if(isset($_POST["submit"])) {
   // form has been submitted


  list($imagew, $imageh) = getimagesize($picture); // get variables for image width and height


 // check image size

   if(($imagew > "640") || ($imageh > "480")) {     // image width or height is greater than 640 x 480


      // resize image and upload
      imagecopyresized("upload/$picture_name", $_FILES["picture"], 0, 0, 0, 0, 640, 480, $imagew, $imageh);


      echo "Image has been resized and uploaded (hopefully)";



    } else {
       //image wasn't too big, upload as normal

      copy($picture, "upload/".$picture_name);
      echo "Image didn't need to be resized and has been uploaded";


   }



} else {

  // form has not been submitted

?>



<form method="post" action="<?= $PHP_SELF ?>" ENCTYPE="multipart/form-data">

Image: <input type="file" name="picture">

<br><br><input type="submit" name="submit" value="submit">


</form>


<?

}


?>

Any ideas?

Thanks again,

Cgraz

[cgraz]

Okay, After a VERY long time of searching and trying everything I could find, I came up with a function that works well for what I want to do, which is resize an image uploaded through a form and save the resized image to my server. Here's the function for anyone searching who comes across this:

<?

function jpgresize ( $srcfile, $dsrd_width, $dsrd_height, $upload_dir, $dsrd_img_name ) {

//function written for using a form to upload an image


 list($imagew, $imageh, $type, $attrib) = getimagesize($srcfile); // get variables for image width and height


 // check image size to make sure it's under desired width x desired height

   if((($imagew > $dsrd_width) || ($imageh > $dsrd_height)) && ($type == "2")) {     // image width or height is greater than what you want

      if($imageh > $imagew) {
         $ratio = ($imageh/$imagew);

         $new_h = $dsrd_height;
         $new_w = ($new_h/$ratio); 
      }

      if($imagew > $imageh) {
         $ratio = ($imagew / $imageh);

         $new_w = $dsrd_width; 
         $new_h = ($new_w/$ratio);
      }

      if($imagew == $imageh) {
         $ratio = "1";

         $new_w = $dsrd_height;
         $new_h = $dsrd_height;
      }


         $dst_img=ImageCreate($new_w,$new_h);  
         $src_img=ImageCreateFromJpeg($srcfile);  

         ImageCopyResized($dst_img,$src_img,0,0,0,0,$new_w,$new_h,ImageSX($src_img),ImageSY($src_img));  

         $newfilename1 = "$upload_dir/$dsrd_img_name"; 
         ImageJpeg($dst_img, $newfilename1); 

         echo "Image was resized and uploaded";



   } else { //image wasn't too big (or was format other than jpeg)... upload as normal

       copy($srcfile, "$upload_dir/$dsrd_img_name");
       echo "Image didn't need to be resized and has been uploaded";


   }


}


?>

And here's how I call the function

jpgresize($picture, "640", "480", "upload", $picture_name);

Thanks for all the help.

Cgraz

[Arc]

woooohoooo! This code works great! Thanks a lot to whoever wrote it. I do wish it could do more than just jp though...

[cgraz]

Arc:

This code will be a little bit more reliable. I altered my function a bit since this post. You'll get much better quality with this:

    function jpgresize($source, $dsrd_width, $dsrd_height, $upload_dir, $dsrd_img_name, $quality = 80) 
    { 
        /* Check for the image's exisitance */ 
        if (!file_exists($source)) { 
            echo 'File does not exist!'; 
        } 
        else { 
            list($imagew, $imageh, $type, $attrib) = getimagesize($source); // get variables for image width and height

        $size = getimagesize($source); // Get the image dimensions and mime type 


        // check image size to make sure it's under desired width x desired height

        if((($imagew > $dsrd_width) || ($imageh > $dsrd_height)) && ($type == "2")) {     // image width or height is greater than what you want

           if($imageh > $imagew) {
              $ratio = ($imageh/$imagew);

              $new_h = $dsrd_height;
              $new_w = ($new_h/$ratio); 
           }

           if($imagew > $imageh) {
              $ratio = ($imagew / $imageh);

              $new_w = $dsrd_width; 
              $new_h = ($new_w/$ratio);
           }

           if($imagew == $imageh) {
              $ratio = "1";

              $new_w = $dsrd_height;
              $new_h = $dsrd_height;
           }

        $resize = imagecreatetruecolor($new_w, $new_h); // Create a blank image 

           /* Check quality option. If quality is greater than 100, return error */ 
           if ($quality > 100) { 
               echo 'The maximum quality is 100. Quality changes only affect JPEG images.'; 
        } 
        else {              

            switch ($size['mime']) { 
                case 'image/jpeg': 
                $im = imagecreatefromjpeg($source); 
                imagecopyresampled($resize, $im, 0, 0, 0, 0, $new_w, $new_h, $size[0], $size[1]); // Resample the original JPEG 
                $newfilename1 = "$upload_dir/$dsrd_img_name"; 
                ImageJpeg($resize, $newfilename1, $quality); 
                break; 

                case 'image/png': 
                $im = imagecreatefrompng($source); 
                imagecopyresampled($resize, $im, 0, 0, 0, 0, $new_w, $new_h, $size[0], $size[1]); // Resample the original PNG 
                imagepng($resize, '', $quality); // Output the new PNG 
                break; 
            } 

            imagedestroy($im); 
           } 

   } else { //image wasn't too big (or was format other than jpeg)... upload as normal

       copy($source, "$upload_dir/$dsrd_img_name");


   }
    } 
}   

Cgraz

[Arc]

Heh, I just cme back here looking for this post cause I tried some more complex images and they were in bad shape.

This new code works much better..thanks again!