title: getting resized product pictures without loading product
body: <p>Regarding the poor performances of my magento homepage (4 seconds computing before it start loading assets) i optimized my source code to go down to 1 second, by removing all the $_product->load that were in my loops.</p>
  
  <p>But i'm facing another issue, i can't call the picture this way anoymore :</p>
  
  <pre><code>&lt;img src="&lt;?php echo $this-&gt;helper('catalog/image')-&gt;init($_product, 'image')-&gt;resize(135); ?&gt;" 
  </code></pre>
  
  <p>so, i began to call thumbnails</p>
  
  <pre><code>&lt;?php echo Mage::getModel('catalog/product_media_config')-&gt;getMediaUrl($_product-&gt;getThumbnail()); ?&gt;
  </code></pre>
  
  <p>but there's few points that annoys me, the 2nd call don't get a default placeholder picture if no picture is found, and the bigger problem is, all the magento's product have only a large res file, which is called if i don't upload a thumbnail for each product (note : i got 1600+ products, i'd like to avoid a manual upload for every single item)</p>
  
  <p>So i have two options : getting th catalog/image helper to work without loading product, or finding a way to generate all the thumbnail with the high res pictures (i looked for an extension doing this, but i guess i'm a bad googler)</p>
  
  <p>EDIT : here's the collection call</p>
  
  <pre><code>$selections_products = Mage::getModel('catalog/product')-&gt;getCollection()
  -&gt;addAttributeToSelect(
      array(
        'name',
        'special_from_date',
        'special_to_date',
        'thumbnail',
        'image',
        'couleur',
        'special_price',
        'url_path',
        'price',
        'format',
        'selection_moment',
        'selection_rouge',
        'selection_blanc',
        'selection_cdc',
        'selection_champagne',
        'selection_exception'
      )
  )
  -&gt;addAttributeToFilter(array(array('attribute'=&gt;'attribute_set_id', 'like' =&gt; '4')))
  -&gt;addAttributeToFilter(
      array(
          array('attribute'=&gt;'selection_moment', 'like' =&gt; '1'),
          array('attribute'=&gt;'selection_rouge', 'like' =&gt; '1'),
          array('attribute'=&gt;'selection_blanc', 'like' =&gt; '1'),
          array('attribute'=&gt;'selection_cdc', 'like' =&gt; '1'),
          array('attribute'=&gt;'selection_champagne', 'like' =&gt; '1'),
          array('attribute'=&gt;'selection_exception', 'like' =&gt; '1')
      )
  );
  $selections_products-&gt;getSelect()-&gt;limit(32);
  </code></pre>
  
  <p>EDIT 2 : foreach on the collection :</p>
  
  <pre><code>&lt;?php $i = 0;
      foreach($selections_products_rouge as $_product): ?&gt;
  &lt;?php if($i==0 || $i==4): ?&gt;
  &lt;tr&gt;
  &lt;?php endif; ?&gt;
      &lt;td&gt;
          &lt;div class="prod-resume"&gt;
              &lt;div class="thumb-wrapper"&gt;
                  &lt;div class="thumb"&gt;
                      &lt;div class="pic-holder"&gt;
                          &lt;a href="&lt;?php echo $_product-&gt;getProductUrl() ?&gt;"&gt;
                              &lt;img height="220" src="&lt;?php echo Mage::getModel('catalog/product_media_config')-&gt;getMediaUrl($_product-&gt;getThumbnail()); ?&gt;"/&gt;
                          &lt;/a&gt;
                      &lt;/div&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
              &lt;h3 class="title"&gt;&lt;?php echo $_product-&gt;getName(); ?&gt;&lt;/h3&gt;
              &lt;div class="type"&gt;
              &lt;?php 
              $cats = $_product-&gt;getCategoryIds();
              $j = 0;
              foreach ($cats as $category_id) {
                  $_cat = Mage::getModel('catalog/category')-&gt;load($category_id);
                  if($_cat-&gt;getLevel() != 2 &amp;&amp; $j &lt; 2 &amp;&amp; $_cat-&gt;getName() != 'Default Category'){
                      echo '&lt;span&gt;'.$_cat-&gt;getName().'&lt;/span&gt;';
                      $j++;
                  }
              }
              $couleur = $_product-&gt;getResource()-&gt;getAttribute('couleur')-&gt;getFrontend()-&gt;getValue($_product);
              $format = $_product-&gt;getResource()-&gt;getAttribute('format')-&gt;getFrontend()-&gt;getValue($_product);
              echo '&lt;span&gt;'.$couleur.'&lt;/span&gt;';
              echo '&lt;span&gt;'.$format.'&lt;/span&gt;';
              ?&gt;
              &lt;/div&gt;
              &lt;?php echo get_promo_stamp($_product); ?&gt;
              &lt;div class="bottom"&gt;
                  &lt;?php echo get_product_price_html($_product,$_taxHelper,$_coreHelper); ?&gt;
                  &lt;div class="btns"&gt;
                      &lt;a href="&lt;?php echo $_product-&gt;getProductUrl() ?&gt;" class="prod"&gt;Fiche produit&lt;/a&gt;
                      &lt;?php if($_product-&gt;isSaleable()): ?&gt;
                      &lt;a href="&lt;?php echo $this-&gt;helper('checkout/cart')-&gt;getAddUrl($_product) ?&gt;" class="basket"&gt;Ajouter au panier&lt;/a&gt;
                      &lt;?php endif; ?&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
              &lt;a href="&lt;?php echo $_product-&gt;getProductUrl() ?&gt;" class="preview btn-popin"&gt;Aperçu&lt;/a&gt;
          &lt;/div&gt;
      &lt;/td&gt;
  &lt;?php if($i==3 || $i==7): ?&gt;
  &lt;/tr&gt;
  &lt;?php endif; ?&gt;
  &lt;?php $i++;endforeach; ?&gt;
  </code></pre>