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GD imagepng function produce corrupted image file

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Join Date: Jun 2007

Posts: 14

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msi_333

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Newbie Poster

GD imagepng function produce corrupted image file

Oct 2nd, 2008

Hi all ,
what i want to do is to resample my large image into smaller resolution image and save it on the server, but the output image is corrupted when i open it in windows image viewer

please help me , here is the code .

 Help with Code Tags 
 php Syntax (Toggle Plain Text) 
 
// The file
$filename = 'd.png';
$percent = 0.5;
 
// Content type
 
 
// Get new dimensions
list($width, $height) = getimagesize($filename);
$new_width = 400;
$new_height = 400;
 
// Resample
$image_p = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefrompng($filename);
imagealphablending($im_dest, false);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
imagesavealpha($image_p, true);
// Output
imagepng($image_e,'aa.png',0);
// The file
$filename = 'd.png';
$percent = 0.5;

// Content type
 

// Get new dimensions
list($width, $height) = getimagesize($filename);
$new_width = 400;
$new_height = 400;

// Resample
$image_p = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefrompng($filename);
imagealphablending($im_dest, false);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
imagesavealpha($image_p, true);
// Output
imagepng($image_e,'aa.png',0);

the output image is attached too ,

Last edited by msi_333; Oct 2nd, 2008 at 12:12 am.

Attached Thumbnails

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Join Date: Jun 2008

Posts: 849

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R0bb0b

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Practically a Posting Shark

Re: GD imagepng function produce corrupted image file

Oct 2nd, 2008

maybe you are having the same problem as this guy:
http://us.php.net/manual/en/function.imagepng.php#79150

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So instead of just
imagepng($image); //DIDNT WORK--CORUPT IMAGE

This worked
imagepng($image,NULL,0,NULL);

Last edited by R0bb0b; Oct 2nd, 2008 at 12:49 am.

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cwarn23

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Re: GD imagepng function produce corrupted image file

Oct 2nd, 2008

Found your problem which I had too when I did my first GD script the last line is incorrect as it has an unsigned variable within the function.

 Help with Code Tags 
 php Syntax (Toggle Plain Text) 
imagepng($image_e,'aa.png',0);
imagepng($image_e,'aa.png',0);

So replace the above with below

 Help with Code Tags 
 php Syntax (Toggle Plain Text) 
imagepng($image_p,'aa.png',0);
imagepng($image_p,'aa.png',0);

Notice the letter 'e' in the first box and the letter 'p' in the second box (after the word image). That is your bug. Although your script shows the letter 'e', it needs to be replaced with the letter 'p'. So the overall code will be:

 Help with Code Tags 
 php Syntax (Toggle Plain Text) 
 
// The file
$filename = 'd.png';
$percent = 0.5;
 
// Content type
 
 
// Get new dimensions
list($width, $height) = getimagesize($filename);
$new_width = 400;
$new_height = 400;
 
// Resample
$image_p = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefrompng($filename);
imagealphablending($im_dest, false);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
imagesavealpha($image_p, true);
// Output
imagepng($image_p,'aa.png',0); //this is the line that has been changed
       
// The file
$filename = 'd.png';
$percent = 0.5;
 
// Content type
 
 
// Get new dimensions
list($width, $height) = getimagesize($filename);
$new_width = 400;
$new_height = 400;

// Resample
$image_p = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefrompng($filename);
imagealphablending($im_dest, false);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
imagesavealpha($image_p, true);
// Output
imagepng($image_p,'aa.png',0); //this is the line that has been changed

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