Question : Know the image type?

I am parsing some pages on a government site and they contain image links like
this:

image_render.aspx?item=011739056&sz=lg

When I navigate to this URL, it doesn't show the image, it shows code:
¿¿¿¿¿ JFIF¿ ¿d¿d¿¿¿¿¿

I have used this code in the past to get these images but I have no idea how to determine the image TYPE because some of them are GIF.

Using simple_html_dom class to parse the HTML after Tidy'ing it up.

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$image = $html2->getElementById('hlHeadImage');
if (isset($image)) {
  if (strpos($image->children(0)->src, 'clearpixel') == 0) {
    $link = $image->children(0)->src;
    $path_parts = pathinfo($link);
    $ext = $path_parts['extension'];
    $image_path =  "part_images/".$ITEM_NO.".".$ext;
    @copy($link."&sz=lg", $image_path);
  }
} else {
  $image = $html2->getElementById('hlLargeImage');
  if (isset($image)) {
    if (strpos($image->children(0)->src, 'clearpixel') == 0) {
      $link = $image->children(0)->src;
      $path_parts = pathinfo($link);
      $ext = $path_parts['extension'];
      $image_path =  "part_images/".$ITEM_NO.".".$ext;
      @copy($link, $image_path);
    }
  }
}

Question is, how can I download these images and maintain the extension?

Answer : Know the image type?

Hi learningunix,

the line checks if the left-most byte of 'num' is '1'.

'&num' is a pointer to the memory address where the first byte of 'num' resides. The '(char)' casts this pointer '&num' (which is a pointer to int) to a pointer to char. Since char is a one byte data type accessing that 'pointer to char' with '' accesses the first byte of the int. In little endian this byte has to be '1' for and 'int' which is '1' - in big endian the first byte would be '0' since the least significant byte is the most right one ...

Hope that helps,

ZOPPO