visualizzare immagini da DB rimpicciolite?

[Coach]

ciao,
ho delle immagini in una cartella ed il nome del file salvato in un database assieme a dei dati.

Siccome l'immagine di suo ha dimensioni 400x400px circa volevo visualizzare nell'elenco dei prodotti un'immagine di 100x100px circa.

Volevo sapere se usando le GD la cosa è fattibile...
cioè riesco a:
1 - prendere le immagini grandi
2 - ridimensionarle a seconda dell'altezza o larghezza
3 - visualizzarle rimpicciolite

risparmio il tempo di caricamento che sarebbe voluto x visualizzare quelle grandi???

[_kime_]

io avevo trovato questo...

    /**
    * Thumbnail Class
    *
    * Creates resized (preview-) images
    *
    * Usage Example:
    * $img = new Thumbnail();
    * echo $img->create_tag("../images/photos/sunflower.jpg");
    *
    * @author   Philipp v. Criegern <criegep@criegern.com>
    * @version  1.0 20.02.2002
    */
    class Thumbnail
    {
        /**
        * Directory where the created thumbnails are stored in (for PHP access)
        * e.g. '/usr/local/apache/htdocs/images/thumbnails'
        * Can be overwritten by global configuration array $_CONFIG['thumbnail_dir_internal']
        *
        * @access public
        */
        var $thumbnail_dir_internal  =  '';

        /**
        * Path to thumbnail directory for browser access
        * e.g. '/images/thumbnails'
        * Can be overwritten by global configuration array $_CONFIG['thumbnail_dir_external']
        *
        * @access public
        */
        var $thumbnail_dir_external  =  '';

        /**
        * Maximum pixel width of created thumbnail
        *
        * @access public
        */
        var $max_width               =  120;

        /**
        * Maximum pixel height of created thumbnail
        *
        * @access public
        */
        var $max_height              =  120;

        /**
        * File name of created thumbnail
        * e.g. 'sunflower.png'
        *
        * @access public
        */
        var $image_name;

        /**
        * Complete image tag for created thumbnail
        * e.g. '[img]/images/thumbnails/sunflower.png[/img]'
        *
        * @access public
        */
        var $image_tag;

        /**
        * Error message if creation fails
        *
        * @access public
        */
        var $error;

        /**
        * Pixel width of created thumbnail
        *
        * @access public
        */
        var $width;

        /**
        * Pixel height of created thumbnail
        *
        * @access public
        */
        var $height;


        /**
        * Thumbnail Constructor
        *
        * @access public
        */
        function Thumbnail ()
        {
            global $_CONFIG;

            if (!empty($_CONFIG['thumbnail_dir_internal']))
            {
                $this->thumbnail_dir_internal  =  $_CONFIG['thumbnail_dir_internal'];
            }
            if (!empty($_CONFIG['thumbnail_dir_external']))
            {
                $this->thumbnail_dir_external  =  $_CONFIG['thumbnail_dir_external'];
            }
        }

        /**
        * Create Thumbnail and return Image Name
        *
        * @access public
        * @param string $parameter Filename of source image
        * @return string Filename of created thumbnail
        */
        function create_name ( $parameter = '' )
        {
            $this->create( $parameter );
            return $this->image_name;
        }

        /**
        * Create Thumbnail and return Image Tag
        *
        * @access public
        * @param string $parameter Filename of source image
        * @return string Complete HTML Image-Tag of created thumbnail
        */
        function create_tag ( $parameter = '' )
        {
            $this->create( $parameter );
            return $this->image_tag;
        }

        /**
        * Create Thumbnail
        *
        * @access private
        * @param string $parameter Filename of source image
        * @return void
        */
        function create ( $imagefile )
        {
            if (strlen($this->thumbnail_dir_internal)  &&  (substr($this->thumbnail_dir_internal, -1) != '/'))
            {
                $this->thumbnail_dir_internal  .=  '/';
            }
            if (strlen($this->thumbnail_dir_external)  &&  (substr($this->thumbnail_dir_external, -1) != '/'))
            {
                $this->thumbnail_dir_external  .=  '/';
            }
            $tmp_name  =  basename($imagefile);
            if (strtolower(substr($tmp_name, -4)) == '.jpg')
            {
                $this->image_name  =  substr($tmp_name, 0, -4) . '.png';
                if (!is_file($this->thumbnail_dir_internal . $this->image_name))
                {
                    $old    =  ImageCreateFromJPEG($imagefile);
                    $old_w  =  ImageSX($old);
                    $old_h  =  ImageSY($old);
                    $this->width   =  $old_w;
                    $this->height  =  $old_h;
                    if ($this->max_width  &&  ($this->width > $this->max_width))
                    {
                        $this->height  =  round($this->height * $this->max_width / $this->width);
                        $this->width   =  $this->max_width;
                    }
                    if ($this->max_height  &&  ($this->height > $this->max_height))
                    {
                        $this->width   =  round($this->width * $this->max_height / $this->height);
                        $this->height  =  $this->max_height;
                    }
                    $new  =  imagecreate($this->width, $this->height);
                    imagecopyresized($new, $old, 0,0, 0,0, $this->width, $this->height, $old_w, $old_h);
                    ImageJPEG($new, $this->thumbnail_dir_internal . $this->image_name);
                    ImageDestroy($new);
                    ImageDestroy($old);
                }
                else
                {
                    $arr  =  getimagesize($this->thumbnail_dir_internal . $this->image_name);
                    $this->width   =  $arr[0];
                    $this->height  =  $arr[1];
                }
                $this->image_tag  =  '<IMG SRC="' . $this->thumbnail_dir_external . $this->image_name 
                                   . '" WIDTH="'  . $this->width
                                   . '" HEIGHT="' . $this->height
                                   . '" BORDER="0">';
            }
            else
            {
                $this->error  =  "Filetype not JPG";
            }
        }
    } 

[Coach]

l'ho provata, ma mi dai dei problemi... nn capisco il xchè mi visualizza l'immagine grande invece che piccola.


P.S: ho modificato le maiuscole delle funzioni GD xchè ho una vers superiore...

[13manuel84]

Ti posto tutti i file che uso io:

[img]thumb.php?blobId=1[/img]

thumb.php

<?
global $blobId;
if(!is_numeric($blobId))
	die("blobId non valido");

include 'connect.inc.php';

$dbQuery = "SELECT blob_type, blob_data FROM file WHERE id_file = $blobId";

$result = mysql_query($dbQuery) or die("Couldn't get file list");

$fileType = @mysql_result($result, 0, "blob_type");
$fileContent = @mysql_result($result, 0, "blob_data");
header("Content-type: $fileType");

	
include 'resize.php';
	
$img_res = imagecreatefromstring($fileContent);
$new_img_res = resize_image($img_res, 60, 80);
unset($img_res);
print_image($new_img_res, 100);
unset($new_img_res);
?>

connect.inc.php -> File di connessione al db

<?
// parametri del database
$db_host = "localhost";
$db_user = "db_user";
$db_password = "db_password";
$db_name = "db_name";

mysql_connect($db_host, $db_user, $db_password)or die("Errore nella connessione: ".mysql_error());
mysql_select_db($db_name) or die("Errore nella selezione del database: ".mysql_error());
?>

resize.php -> Fa il resize dell'immagine

<?
function resize_image($img_res, $maxX, $maxY) {
  $actualX=imagesx($img_res);
  $actualY=imagesy($img_res);
  $newX=$maxX;
  $newY=$maxY;
  $tmp_img_res = imagecreatetruecolor($newX, $newY);
  $res = imagecopyresampled($tmp_img_res, $img_res, 0, 0, 0, 0, $newX, $newY, $actualX, $actualY);
  return $tmp_img_res;
}

function save_image($img_res, $filename, $quality=80) {
  imagejpeg($img_res, $filename, $quality);
}

function print_image($img_res, $quality=100) {
  header('Content-Type: image/jpeg');
  imagejpeg($img_res,NULL, $quality);
}
?>

Devi naturalmente modificare la query, i nomi delle variabili, e naturalmente le dimensioni che vuoi in resize.php a seconda dei nomi dei campi che hai nel tuo db, per il resto è tutto a posto.

[luqwe]

puoi farlo tranquillamente.
Io avevo postato qualche cosa qualche tempo fa:
http://forum.html.it/forum/showthrea...49#post6009349

Devi comunque assicurarti di avere il supporto per le gd2 sul php.

[13manuel84]

in alternativa puoi usare questo resize.php che ti mantiene costanti le proporzioni senza sfigurarti l'immagine:

<?
function resize_image($img_res, $maxX, $maxY) {
  $actualX=imagesx($img_res);
  $actualY=imagesy($img_res);
		
  if ($actualY>$maxY){
    $newY = $maxY;
    $newX = ($actualX/$actualY)*$newY;
    if ($newX>$maxX)
      $newX = $maxX; $newY = ($actualY/$actualX)*$newX;
  }elseif ($actualX>$maxX){
    $newX = $maxX;
    $newY = ($actualY/$actualX)*$newX;
    if ($newY>$maxY)
      $newY = $maxY; $newX=($actualX/$actualY)*$newY;
  }else{
    $newX = $actualX;
    $newY = $actualY;
  }
  $tmp_img_res = imagecreatetruecolor($newX, $newY);
		
  $res = imagecopyresampled($tmp_img_res, $img_res, 0, 0, 0, 0, $newX, $newY, $actualX, $actualY);

  return $tmp_img_res;
}

function save_image($img_res, $filename, $quality=100) {
  imagejpeg($img_res, $filename, $quality);
}

function print_image($img_res, $quality=100) {
  header('Content-Type: image/jpeg');
  imagejpeg($img_res,NULL, $quality);
}
?>

[13manuel84]

p.s. non vorrei prendermi il merito di quelle funzioni che non ho fatto io, per correttezza ti posto il link della discussione a cui fanno riferimento: http://forum.html.it/forum/showthrea...hreadid=592358

Thank's to daniele_dll