As touched on previously, many cameras and image manipulation software will include an embedded thumbnail for an image. You can extract this thumbnail using the exif_thumbnail function:
<?php $image = "image.jpg"; $thumbnail = exif_thumbnail($image, $width, $height, $type); echo "<img width='$width' height='$height' src='data:image;base64,".base64_encode($thumbnail)."'>"; ?>
Keep in mind that the thumbnail generated here is from the Exif data – there are other ways to create a thumbnails using many of the PHP image functions.