Resize Image PHP for Transparant Png or Gif Image

$vdir_upload = FCPATH.'public/images/logo_theme/';

$vfile_upload = $vdir_upload . $this->upload->file_name;

switch($this->upload->file_ext)

{

case '.jpg':

case '.jpeg':

$im_src = imagecreatefromjpeg($vfile_upload);

break;

case '.gif':

$im_src = imagecreatefromgif($vfile_upload);

break;

case '.png':

$im_src = imagecreatefrompng($vfile_upload);

break;

default:

$im_src = false;

break;

}

$src_width = imageSX($im_src);

$src_height = imageSY($im_src);

$dst_width = 120;

$dst_height = 20;

$im = imagecreatetruecolor($dst_width,$dst_height);

//==========================================

$trnprt_indx = imagecolortransparent($im_src);

// If we have a specific transparent color

if ($trnprt_indx >= 0) {

// Get the original image's transparent color's RGB values

$trnprt_color = imagecolorsforindex($im_src, $trnprt_indx);

// Allocate the same color in the new image resource

$trnprt_indx = imagecolorallocate($im, $trnprt_color['red'], $trnprt_color['green'], $trnprt_color['blue']);

// Completely fill the background of the new image with allocated color.

imagefill($im, 0, 0, $trnprt_indx);

// Set the background color for new image to transparent

imagecolortransparent($im, $trnprt_indx);

}

// Always make a transparent background color for PNGs that don't have one allocated already

elseif ($this->upload->file_ext == '.png') {

// Turn off transparency blending (temporarily)

imagealphablending($im, false);

// Create a new transparent color for image

$color = imagecolorallocatealpha($im, 0, 0, 0, 127);

// Completely fill the background of the new image with allocated color.

imagefill($im, 0, 0, $color);

// Restore transparency blending

imagesavealpha($im, true);

}

//===========================================

imagecopyresampled($im, $im_src, 0, 0, 0, 0, $dst_width, $dst_height, $src_width, $src_height);

switch($this->upload->file_ext)

{

case '.jpg':

case '.jpeg':

imagejpeg($im,$vdir_upload . "mobile_" . $this->upload->file_name);

break;

case '.gif':

imagegif($im,$vdir_upload . "mobile_" . $this->upload->file_name);

break;

case '.png':

imagepng($im,$vdir_upload . "mobile_" . $this->upload->file_name);

break;

default:

break;

}

imagedestroy($im_src);

imagedestroy($im);