[eluser]Unknown[/eluser]
Hello everybody,
I'm using CI for lots of my projects and encountered recently a problem of transparency with my GIF images when using image_lib to resize it. The transparent background was turned into black. After a quick seach in the forum I found a solution here :
http://ellislab.com/forums/viewthread/62955/
The only problem I found among all posts was that guys (and girls ^^) where speaking about hacking CI Core to change the behavior of the image_lib library.
May I suggest to Extend the native library instead of hacking it :
Create in "libraries" a file called MY_Image_lib.php and paste the following code into it.
Then try and enjoy ^^
Code:
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
// Extends the native Image_lib library
class MY_Image_lib extends CI_Image_lib {
function MY_Image_lib()
{
parent::CI_Image_lib(); // Extends the image_lib library
}
// Hack allowing to keep the transparency of GIF images
function image_process_gd($action = 'resize')
{
$v2_override = FALSE;
if ($action == 'crop')
{
// If the target width/height match the source then it's pointless to crop, right?
// So if dynamic output isn't on, then we'll return true so the user thinks
// the process succeeded. It'll be our little secret...
if ($this->width >= $this->orig_width AND $this->height >= $this->orig_height AND $this->dynamic_output !== TRUE)
{
return TRUE;
}
// Reassign the source width/height if cropping
$this->orig_width = $this->width;
$this->orig_height = $this->height;
// GD 2.0 has a cropping bug so we'll test for it
if ($this->gd_version() !== FALSE)
{
$gd_version = str_replace('0', '', $this->gd_version());
$v2_override = ($gd_version == 2) ? TRUE : FALSE;
}
}
else
{
// If the target width/height match the source, AND if
// the new file name is not equal to the old file name
// we'll simply make a copy of the original with the new name
if (($this->orig_width == $this->width AND $this->orig_height == $this->height) AND ($this->source_image != $this->new_image))
{
if ( ! @copy($this->full_src_path, $this->full_dst_path))
{
$this->set_error('imglib_copy_failed');
return FALSE;
}
@chmod($this->full_dst_path, DIR_WRITE_MODE);
return TRUE;
}
// If resizing the x/y axis must be zero
$this->x_axis = 0;
$this->y_axis = 0;
}
// Create the image handle
if ( ! ($src_img = $this->image_create_gd()))
{
return FALSE;
}
// Create The Image
//
// old conditional which users report cause problems with shared GD libs who report themselves as "2.0 or greater"
// it appears that this is no longer the issue that it was in 2004, so we've removed it, retaining it in the comment
// below should that ever prove inaccurate.
//
// if ($this->image_library == 'gd2' AND function_exists('imagecreatetruecolor') AND $v2_override == FALSE)
if ($this->image_library == 'gd2' AND function_exists('imagecreatetruecolor'))
{
$create = 'imagecreatetruecolor';
$copy = 'imagecopyresampled';
}
else
{
$create = 'imagecreate';
$copy = 'imagecopyresized';
}
$dst_img = $create($this->width, $this->height);
// HERE IS THE HACK http://ellislab.com/forums/viewthread/92355/
// keeping transparency
$transparent_index = imagecolortransparent($src_img);
if ($transparent_index >= 0) {
imagepalettecopy($src_img, $dst_img);
imagefill($dst_img, 0, 0, $transparent_index);
imagecolortransparent($dst_img, $transparent_index);
imagetruecolortopalette($dst_img, true, 256);
}
$copy($dst_img, $src_img, 0, 0, $this->x_axis, $this->y_axis, $this->width, $this->height, $this->orig_width, $this->orig_height);
// Show the image
if ($this->dynamic_output == TRUE)
{
$this->image_display_gd($dst_img);
}
else
{
// Or save it
if ( ! $this->image_save_gd($dst_img))
{
return FALSE;
}
}
// Kill the file handles
imagedestroy($dst_img);
imagedestroy($src_img);
// Set the file to 777
@chmod($this->full_dst_path, DIR_WRITE_MODE);
return TRUE;
}
}
?>
