PHP Detecting if source image url link leads to a “broken” image?

Question

Suppose you have a thumbnail generator script that accepts source images in the form of a URL. Is there a way to detect if the source URL is \"broken\" - whether nonexistent

Answer 1

Fast Solution for broken or not found images link
i suggest you that don't use getimagesize() because it will 1st download image then it will check images size+if this will not image then it will throw exception so use below code

if(checkRemoteFile($imgurl))
{
//found url, its mean
echo "this is image";
}

function checkRemoteFile($url)
{
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL,$url);
    // don't download content
    curl_setopt($ch, CURLOPT_NOBODY, 1);
    curl_setopt($ch, CURLOPT_FAILONERROR, 1);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    if(curl_exec($ch)!==FALSE)
    {
        return true;
    }
    else
    {
        return false;
    }
}

Note: this current code help you to identify broken or not found url image this will not help you to identify image type or headers