PHP: imagecreatefromgif

Description

resource imagecreatefromgif ( string filename )

imagecreatefromgif() returns an image identifier representing the image obtained from the given filename.

imagecreatefromgif() returns an empty string on failure. It also outputs an error message, which unfortunately displays as a broken link in a browser. To ease debugging the following example will produce an error GIF:
Example 1. Example to handle an error during creation (courtesy vic at zymsys dot com)

<?php function LoadGif ($imgname) { $im = @imagecreatefromgif ($imgname); /* Attempt to open */ if (!$im) { /* See if it failed */ $im = imagecreate (150, 30); /* Create a blank image */ $bgc = imagecolorallocate ($im, 255, 255, 255); $tc = imagecolorallocate ($im, 0, 0, 0); imagefilledrectangle ($im, 0, 0, 150, 30, $bgc); /* Output an errmsg */ imagestring ($im, 1, 5, 5, "Error loading $imgname", $tc); } return $im; } ?>

Note: GIF support was removed from the GD library in Version 1.6, and added back in Version 2.0.28. This function is not available between these versions.

Tip: You can use a URL as a filename with this function if the fopen wrappers have been enabled. See fopen() for more details on how to specify the filename and Appendix L for a list of supported URL protocols.

Warning

Windows versions of PHP prior to PHP 4.3.0 do not support accessing remote files via this function, even if allow_url_fopen is enabled.

User Contributed Notes
imagecreatefromgif

jason at null dot zzz
06-Apr-2004 04:13


thanks yamasoft for the gif to png lib.  it works!  but, there is one bug.  i changed line 1003 to this:



if(isset($this->m_img->m_bTrans) && $this->m_img->m_bTrans && ($nColors > 0)) {



because i was getting an error that m_bTrans is undefined.  i think this is because my gif has no transparency.  after i updated this line, there were no problems.



thanks!



-j

josh [ a t ] OnlineComics [ d o t ] net
07-Oct-2003 10:36


I just installed gif2png on my server, and it took a little research on my part to figure out that this...



passthru("$path/gif2png -O $image_path/image.gif")



will not work if safe mode is on. If you're on a shared server, it probably is. You don't need to turn safe mode off, however, just set the safe_mode_exec_dir variable in your php.ini file to the directory where you installed gif2png. Then you'll be able to execute the program from your PHP script.

29-Jun-2003 06:26


function LoadGif ($imgname) {

    $im = @ImageCreateFromGIF ($imgname); /* Attempt to open */

    if (!$im) { /* See if it failed */

        $im = ImageCreate (150, 30); /* Create a blank image */

        $bgc = ImageColorAllocate ($im, 255, 255, 255);

        $tc  = ImageColorAllocate ($im, 0, 0, 0);

        ImageFilledRectangle ($im, 0, 0, 150, 30, $bgc); 

        /* Output an errmsg */

        ImageString($im, 1, 5, 5, "Error loading $imgname", $tc); 

    }

    return $im;

}

18-Apr-2003 11:34


re: 09-May-2002 11:31



Seems gif2png is no longer at http://www.tuxedo.org/~esr/gif2png/

I found a Win32 version at http://www.r1ch.net/stuff/gif2png/

(for the Unix and source, see http://catb.org/~esr/gif2png/ )



In Win32,

  passthru("gif2png $filename");

works fine if gif2png.exe is in the path.

It will overwrite the file with .png extension, so be careful,or use temp files as in the post referenced above (without the  -O; type "gif2png" at the command line for the options).



I had a problem with exceeding the default 30 second execution time limit in PHP, so I added this line

  set_time_limit(0); // some odd gifs take a long time (example, a 25K gif, 700x700, mostly blank)

geoffrey at poulet dot org
27-Feb-2003 09:22


After hours of search, I've finally found a program which can convert JPG to GIF.

IJG - The Independent JPEG Group's JPEG software

Version 6 which support GIF (read and write with LZW)

and the version 6b which support GIF (write only without LZW)



The name of the file is: jpegsrc.v6.tar.gz

fezber at yamasoft dot com
13-Feb-2003 09:27


For users who just want GIF read (not write) support but:

1) Don't want to patch GD libs

2) Don't want to recompile something

3) Don't have permissions to install conversion packages

4) Any other reason...



I created a small php script (around 25KB) which lets you load a GIF from a file (you even can specify the image index on animated GIFs) and then convert it to a PNG or BMP file.



If I take one example:



<?

include("gif.php");



$gif = gif_loadFile("./test.gif");



if($gif) {

    // GIF file successfully opened

    if(gif_outputAsPNG($gif, "./test.png")) {

        // Now, just use ImageCreateFromPng...

        $img = ImageCreateFromPng("./test.png");



        if($img) {

            header("Content-Type: image/jpeg");

            ImageJPEG($img);

            ImageDestroy($img);

        }

        else {

            // Could NOT open PNG

        }

    }

    else {

        // Could NOT convert GIF to PNG...

    }

}

else {

    // GIF not loaded...

}

?>



Of course, it's slower than using appropriate software and/or libraries but it's quite useful for reading occasionaly some GIF files.



You'll find the gif.php source code at: http://www.yamasoft.com/php-gif.zip



Fabien

Ady at freebsd dot ady dot ro
11-Jan-2003 01:20


FreeBSD users are lucky to have the option of compiling GIF support in GD2.x through the ports system.

All you need to do is to export the "WITH_LZW=yes" global variable when compiling the graphics/gd2 port, e.g.:



# cd /usr/ports/graphics/gd2

# export WITH_LZW=yes

# make && make install



Then recompile and (re)install the www/mod_php4 port and you are in business... :)



Good luck!

unknown at hotmail dot com
14-Nov-2002 08:00


If GD doesn't support GIFs & gif2png is not available & you are not an administrator, you can install it in your account like this:



create do.php:

<? 

  global $do;

  passthru($do);

?>



then upload gif2png-2.4.6.tar.gz, unpack and install it:

do.php?do=tar+-xvzf+gif2png-2.4.6.tar.gz

do.php?do=gif2png-2.4.5/configure

do.php?do=make



Then remove all files except gif2png. Don't forget to remove do.php as it is a serious security hole in your system. 



Njoy!



Anze

senbei at terra dot es
09-May-2002 12:31


Since gif support is removed from the more recent GD libraries, you can still use it via an external program.


I've read somewhere about using ImageMagick and I tried myself but it's a quite big package and needs the X11 libs which are not available in some servers.


The other option I found is to use a little prog "gif2png" http://www.tuxedo.org/~esr/gif2png/


to convert gif files to png ones. It works under Unix and dos/win32/winnt and is very straightforward.


If you need to modify an user uploaded gif file to save it into your site just use this:





$path=$_FILES["photo"]["tmp_name"];


passthru("/usr/bin/gif2png -d -O ".$path);


$src_img=imagecreatefrompng( dirname($path)."/".basename($path, ".gif").".png");





This will convert the gif to a png and delete the gif file, then it will open the png with the GDlib so you can perform any operation on it.

philikon at gmx dot net
25-Jun-2001 10:50


Patches to the GD library that make GIF support available can be found at


http://www.rime.com.au/gd/

chuckg at infinite9 dot com
22-Mar-2001 02:05


I just thought I'd let you guys know of a workaround for the lack of Gif support in the latest GD...aside from adding the patch.  It works just as good, from what I can tell, and is quite nice ;)





Here goes:


<?


//Just grab some general image info


$img = "path/to/image.gif";


$imageInfo = GetImagesize($img);





if ( $imageInfo[2] == 1 ) {


   //it's a gif


   $file = fread(fopen($path, "r"), filesize($path));





   $fileHeader = "image/gif";


   Header("Content-Type: ".$fileHeader);


   echo $file;


   fclose($file);


}


?>





basically what that does is reads the file..through the "GetImageSize", which still returns if it's a GIF or not, (thank god), then if it's a gif, opens the file through normal filestream, sets the header to image type "gif" then prints it out.  Same as doing "ImageCreateFromGif($img)" and "ImageGif($img)", except that it doesn't require GD Gif support.  If you have any questions just ask me via email (chuckg@infinite9.com)

anthony dot atkins at vt dot edu
16-May-2000 08:05


<pre>


function myImageCreateFromGif($file_or_url) {





        $dummy_file = "/tmp/dummy.gif";





        # if this is a url, use fopen to get the file data, then 


        # save it to a dummy file


        if (preg_match("/(http|ftp):\/\//i", $file_or_url)) {


                # open the file using fopen, which supports remote URLs


                $input = fopen($file_or_url, "rb");





                # read the contents of the file


                # will accept files up to 10Mb, but will probably get 


                # and EOF before that, we have to do it this way because


                # filesize isn't designed to work with URLs.  sigh.


                $image_data = fread($input, 10000000);





                fclose($input);





                # write the contents to a dummy file


                $output = fopen("$dummy_file", "wb");


                fwrite($output, $image_data);


                fclose($output);





                # create the gif from the dummy file


                $image = ImageCreateFromGif($dummy_file);





                # get rid of the dummy file


                unlink($dummy_file);





        }





        # if it's not a URL, we can simply open the image directly


        else {


                $image = ImageCreateFromGif($file_or_url);


        }





        if ($image) { return $image; }


        else { return 0; }


}








if (!$url) { $url = "http://scholar.lib.vt.edu/images/cornholio.gif";}


$image = myImageCreateFromGif($url);





if ($image == "" || $image == 0) {


        print "<p>No Image data was returned...</p>\n";


}


else { 


        header("Content-Type: image/gif\n\n");


        ImageGif($image);


}





?>


</pre>