Not enough information was provided for us to be able
to handle this bug. Please re-read the instructions at
http://bugs.php.net/how-to-report.php

If you can provide more information, feel free to add it
to this bug and change the status back to "Open".

Thank you for your interest in PHP.

More info:

- PHP is run as CGI
- using original windows binary pack
- php_gd2.dll from original windows binary pack
- web server: Apache 2.0.45

Imagecreatefrompng() is used in following code:

//$image_file_url ... URL to the source 24-bit PNG file

	$image_base = ImageCreateTrueColor($map_width, $map_height);
	$white = ImageColorExact($image_base, 255, 255, 255);
	ImageFill($image_base, 0, 0, $white);

	// ........

	$input = fopen($image_file_url, "rb");
	$image_data = fread($input, 2000000);
	fclose($input);

	$image_file = tempnam("", "gd".rand(0, 10000));
	$output = fopen($image_file, "w+b");
	fwrite($output, $image_data);
	fclose($output);

	$image_tmp = ImageCreateFromPNG($image_file); // ERROR

	// ........

It just looks like your image is broken, can you put up a runnable script + image in a tarball (or send it to me by mail) to verify?

Derick

Not really a bug; fread() will now (correctly!) return data in packet sized chunks when reading from network streams, as it did in PHP 4.2.x and earlier.

Technically, your script is broken; you should either do this:

<?php
$data = "";
$fp = fopen("http://....");
do {
   $chunk = fread($fp, 8192);
   if (strlen($chunk) == 0) {
      break;
   }
   $data .= $chunk;
} while (true);
fclose($fp);
?>

this:
<?php
$data = file_get_contents("http://...");
?>

or this:
<?php
copy("http://...", tempnam("", "gd"));
?>

I'm making this a documentation problem, because the fread() manual page has never mentioned this fact, despite it being the behaviour since forever.

One final note; the file_get_contents() and copy() functions were themselves suffering from a similar problem to that of your script; I've committed a fix to CVS, so you need to either use the fread() loop approach, or get the next stable snapshot (due in an hour or so).

of course, the copy() version should look like this:
<?php
$local = tempnam("", "gd");
copy("http://", $local);
?>
otherwise you don't know where you copied it to...

I have also intermittently encountered this error.

Running PHP on Xcalibre.co.uk
http://daffy.xcalibre.co.uk/phpinfo.php
I believe they run Slackware.

My images were created by the imagepng() and are edited by php only.

My first thought was that two instances of the script were accessing the same image?

Sorry, but your problem does not imply a bug in PHP itself.  For a
list of more appropriate places to ask for help using PHP, please
visit http://www.php.net/support.php as this bug system is not the
appropriate forum for asking support questions. 

Thank you for your interest in PHP.

i made a script to add dots to an image and if you run it to many times you also get the error "Fatal error: imagecreatefrompng(): gd-png: fatal libpng error: IDAT: CRC"

i run mandrake linux 9.2
apache 2
php 4.3.3
gdlib 2