PHP's strlen function behaving strangely - php

Question

Please consider the following code:
$imagePath = "https://s22.postimg.org/3k3o9ly8t/testigo.jpg";
$imagedata = get that image data through curl and store in this variable;
echo strlen($imagedata); // outputs 4699
if(strlen($imagedata) == 4699 ) {
echo "length is 4699";
}
The above if-condition never becomes true even though the strlen value is 4600. It seems very strange; am I missing anything? I've already tried mb_strlen, but to no avail.
Update:
It seems to work for certain images, but not for the following image.
Code:
$strImageURL = "https://s22.postimg.org/3k3o9ly8t/testigo.jpg";
$strImageData = getData($strImageURL);
echo "<br />" . strlen($strImageData);
if(strlen($strImageData) === 4699) {
echo "true";
}
function getData($strSubmitURL)
{
$strData = null;
$ch = curl_init();
//return parameter
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 120);
curl_setopt($ch, CURLOPT_TIMEOUT, 140);
//site name
curl_setopt($ch, CURLOPT_URL,$strSubmitURL);
// don' verify ssl host
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER,false);
$strData = curl_exec ($ch);
if (!$strData) {
//die ("cURL error: " . curl_error ($ch) . "\n");
return '';
}
curl_close ($ch);
unset($ch);
return $strData;
}

Answer 1

This works for me:
$url = "http://static.bbci.co.uk/frameworks/barlesque/2.51.4/orb/4/img/bbc-blocks-dark.png";
$imagedata = file_get_contents($url);
//echo strlen($imagedata); // outputs 1020
if(strlen($imagedata) == 1020 ) {
echo "length is 1020";
}
And as further troubleshooting, I would try a var_dump(get_defined_vars()); at the end of your code and inside the if statement to see whats going on.
//Edit/Update:
Using your url, and also putting in a var dump twice:
$url = "http://s22.postimg.org/3k3o9ly8t/testigo.jpg";
$imagedata = file_get_contents($url);
$strlen = strlen($imagedata); // outputs 4669
var_dump($strlen);
if($strlen == 4669 ) {
echo "length is 4669 \n";
var_dump($strlen);
}
returns:
PhpMate running PHP 5.3.15 with (/usr/bin/php)
>>> untitled
int(4669)
length is 4669
int(4669)

Answer 2

strlen() is used to count the bytes that a string equates an one character does not necessarily equal 1 byte in UTF-8
Another issue could be type-casting since PHP has such loose rules about this. Would this work for you?
if((int)strlen($imagedata) == 4600 ) {
echo "length is 4600";
}
or
if(strlen($imagedata) == '4600' ) {
echo "length is 4600";
}