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Hi I have a class for resizing images (resizeManager.php):

        Class ResizeManager
    {
        // *** Class variables
        private $image;
        private $width;
        private $height;
        private $imageResized;

        function __construct($fileName)
        {
            // *** Open up the file
            $this->image = $this->openImage($fileName);

            // *** Get width and height
            $this->width  = imagesx($this->image);
            $this->height = imagesy($this->image);
        }

        ## --------------------------------------------------------

        private function openImage($file)
        {
            // *** Get extension
            $extension = strtolower(strrchr($file, '.'));

            switch($extension)
            {
                case '.jpg':
                case '.jpeg':
                    $img = @imagecreatefromjpeg($file);
                    break;
                case '.gif':
                    $img = @imagecreatefromgif($file);
                    break;
                case '.png':
                    $img = @imagecreatefrompng($file);
                    break;
                default:
                    $img = false;
                    break;
            }
            return $img;
        }

        ## --------------------------------------------------------

        public function resizeImage($newWidth, $newHeight, $option="auto")
        {
            // *** Get optimal width and height - based on $option
            $optionArray = $this->getDimensions($newWidth, $newHeight, $option);

            $optimalWidth  = $optionArray['optimalWidth'];
            $optimalHeight = $optionArray['optimalHeight'];


            // *** Resample - create image canvas of x, y size
            $this->imageResized = imagecreatetruecolor($optimalWidth, $optimalHeight);
            imagecopyresampled($this->imageResized, $this->image, 0, 0, 0, 0, $optimalWidth, $optimalHeight, $this->width, $this->height);


            // *** if option is 'crop', then crop too
            if ($option == 'crop') {
                $this->crop($optimalWidth, $optimalHeight, $newWidth, $newHeight);
            }
        }

        ## --------------------------------------------------------

        private function getDimensions($newWidth, $newHeight, $option)
        {

           switch ($option)
            {
                case 'exact':
                    $optimalWidth = $newWidth;
                    $optimalHeight= $newHeight;
                    break;
                case 'portrait':
                    $optimalWidth = $this->getSizeByFixedHeight($newHeight);
                    $optimalHeight= $newHeight;
                    break;
                case 'landscape':
                    $optimalWidth = $newWidth;
                    $optimalHeight= $this->getSizeByFixedWidth($newWidth);
                    break;
                case 'auto':
                    $optionArray = $this->getSizeByAuto($newWidth, $newHeight);
                    $optimalWidth = $optionArray['optimalWidth'];
                    $optimalHeight = $optionArray['optimalHeight'];
                    break;
                case 'crop':
                    $optionArray = $this->getOptimalCrop($newWidth, $newHeight);
                    $optimalWidth = $optionArray['optimalWidth'];
                    $optimalHeight = $optionArray['optimalHeight'];
                    break;
            }
            return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);
        }

        ## --------------------------------------------------------

        private function getSizeByFixedHeight($newHeight)
        {
            $ratio = $this->width / $this->height;
            $newWidth = $newHeight * $ratio;
            return $newWidth;
        }

        private function getSizeByFixedWidth($newWidth)
        {
            $ratio = $this->height / $this->width;
            $newHeight = $newWidth * $ratio;
            return $newHeight;
        }

        private function getSizeByAuto($newWidth, $newHeight)
        {
            if ($this->height < $this->width)
            // *** Image to be resized is wider (landscape)
            {
                $optimalWidth = $newWidth;
                $optimalHeight= $this->getSizeByFixedWidth($newWidth);
            }
            elseif ($this->height > $this->width)
            // *** Image to be resized is taller (portrait)
            {
                $optimalWidth = $this->getSizeByFixedHeight($newHeight);
                $optimalHeight= $newHeight;
            }
            else
            // *** Image to be resizerd is a square
            {
                if ($newHeight < $newWidth) {
                    $optimalWidth = $newWidth;
                    $optimalHeight= $this->getSizeByFixedWidth($newWidth);
                } else if ($newHeight > $newWidth) {
                    $optimalWidth = $this->getSizeByFixedHeight($newHeight);
                    $optimalHeight= $newHeight;
                } else {
                    // *** Sqaure being resized to a square
                    $optimalWidth = $newWidth;
                    $optimalHeight= $newHeight;
                }
            }

            return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);
        }

        ## --------------------------------------------------------

        private function getOptimalCrop($newWidth, $newHeight)
        {

            $heightRatio = $this->height / $newHeight;
            $widthRatio  = $this->width /  $newWidth;

            if ($heightRatio < $widthRatio) {
                $optimalRatio = $heightRatio;
            } else {
                $optimalRatio = $widthRatio;
            }

            $optimalHeight = $this->height / $optimalRatio;
            $optimalWidth  = $this->width  / $optimalRatio;

            return array('optimalWidth' => $optimalWidth, 'optimalHeight' => $optimalHeight);
        }

        ## --------------------------------------------------------

        private function crop($optimalWidth, $optimalHeight, $newWidth, $newHeight)
        {
            // *** Find center - this will be used for the crop
            $cropStartX = ( $optimalWidth / 2) - ( $newWidth /2 );
            $cropStartY = ( $optimalHeight/ 2) - ( $newHeight/2 );

            $crop = $this->imageResized;
            //imagedestroy($this->imageResized);

            // *** Now crop from center to exact requested size
            $this->imageResized = imagecreatetruecolor($newWidth , $newHeight);
            imagecopyresampled($this->imageResized, $crop , 0, 0, $cropStartX, $cropStartY, $newWidth, $newHeight , $newWidth, $newHeight);
        }

        ## --------------------------------------------------------

        public function saveImage($savePath, $imageQuality="100")
        {
            // *** Get extension
            $extension = strrchr($savePath, '.');
            $extension = strtolower($extension);

            switch($extension)
            {
                case '.jpg':
                case '.jpeg':
                    if (imagetypes() & IMG_JPG) {
                        imagejpeg($this->imageResized, $savePath, $imageQuality);
                    }
                    break;

                case '.gif':
                    if (imagetypes() & IMG_GIF) {
                        imagegif($this->imageResized, $savePath);
                    }
                    break;

                case '.png':
                    // *** Scale quality from 0-100 to 0-9
                    $scaleQuality = round(($imageQuality/100) * 9);

                    // *** Invert quality setting as 0 is best, not 9
                    $invertScaleQuality = 9 - $scaleQuality;

                    if (imagetypes() & IMG_PNG) {
                         imagepng($this->imageResized, $savePath, $invertScaleQuality);
                    }
                    break;

                // ... etc

                default:
                    // *** No extension - No save.
                    break;
            }

            imagedestroy($this->imageResized);
        }




    }

In my page (mypage.php) I want to resize my uploaded image only if its width>800px or height>600px.

So I wrote:

list($width, $height, $type, $attr) = getimagesize($_FILES['pictures']['tmp_name'][$number]); 

if($width>800 || $height>600)
{
 $resizemgr = new ResizeManager($_FILES['pictures']['tmp_name'][$number]);
    //then the actual resizing                      
    [...]
}
else

$ret=@move_uploaded_file($_FILES['pictures']['tmp_name'][$number],$destinationFile); 

But I receive these errors

Warning: imagesx(): supplied argument is not a valid Image resource in resizeManager.php 

Warning: imagesy(): supplied argument is not a valid Image resource in resizeManager.php 

Can I point to a temporary file this way?

thanks

luca

4
  • What does $this -> openImage do / return? Commented Apr 24, 2011 at 13:41
  • Can you post the code for the openImage function in your original post (from the ResizeManager class)? Commented Apr 24, 2011 at 14:02
  • 1
    tmp_name file name is .tmp extenstion ! so in openimage function $img return false ! Commented Apr 24, 2011 at 14:17
  • You need to use the extension from the actual file name and not the temporary file name because as Davood said, the extension isn't the same. Commented Apr 24, 2011 at 14:26

1 Answer 1

4

Test Below Example :

<form method="post" enctype="multipart/form-data" action="">
<input type="file" name="file" />
<div class="td" style="width: 100%; text-align: left;"><button type="submit">OK</button></div>
</form>
<?php
if( isset( $_FILES['file'] ) )
{
    $img = file_get_contents( $_FILES['file']['tmp_name'] );
    $image = imagecreatefromstring( $img );
    echo imagesx( $image );
}
?> 
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2 Comments

Still telling me invalid Image resource
imagesx takes in the image resource, not the filename.

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