If THUMBNAIL_ALLOW_LARGER configuration parameter is set to "false" and desired image is bigger than original, the product_thumb.php works Ok, making a copy of original image so avoiding pixelate it.

But tep_image function creates an <IMG> tag with the WIDTH and HEIGHT desired attributes, not the original ones, so you will see a pixelated image anyway. This contribution is intended to solve this problem: if image will not be resized to a larger one, <IMG> tag will include original size of image.

This contribution is only for those who want not to resize from small to bigger images. Please, do not install if you prefer to let them to resize.

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