PHP Scales the PNG image to support a transparent background

PHP Scales the PNG image to support a transparent background

function Smart_resize_image ($file, $width = 0, $height = 0, $proportional = false, $output = ' file ', $delete _original = t Rue, $use _linux_commands = False)

{

if ($height <= 0 && $width <= 0) {

return false;

}

$info = getimagesize ($file);

$image = ';

$final _width = 0;

$final _height = 0;

List ($width _old, $height _old) = $info;

if ($proportional) {

if ($width = = 0) $factor = $height/$height _old;

ElseIf ($height = = 0) $factor = $width/$width _old;

else $factor = min ($width/$width _old, $height/$height _old);

$final _width = Round ($width _old * $factor);

$final _height = Round ($height _old * $factor);

}

else {

$final _width = ($width <= 0)? $width _old: $width;

$final _height = ($height <= 0)? $height _old: $height;

}

Switch ($info [2]) {

Case Imagetype_gif:

$image = Imagecreatefromgif ($file);

Break

Case IMAGETYPE_JPEG:

$image = Imagecreatefromjpeg ($file);

Break

Case Imagetype_png:

$image = Imagecreatefrompng ($file);

Break

Default

return false;

}

$image _resized = Imagecreatetruecolor ($final _width, $final _height);

if ($info [2] = = Imagetype_gif) | | ($info [2] = = Imagetype_png)) {

$trnprt _indx = imagecolortransparent ($image);

If we have a specific transparent color

if ($trnprt _indx >= 0) {

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

$trnprt _color = Imagecolorsforindex ($image, $trnprt _indx);

Allocate the same color in the new image resource

$trnprt _indx = imagecolorallocate ($image _resized, $trnprt _color[' red '), $trnprt _color[' green ', $trnprt _color[' Blue ']);

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

Imagefill ($image _resized, 0, 0, $trnprt _indx);

Set the background color for new image to Transparent

Imagecolortransparent ($image _resized, $trnprt _indx);

}

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

ElseIf ($info [2] = = Imagetype_png) {

Turn off transparency Blending (temporarily)

Imagealphablending ($image _resized, false);

Create a new transparent color for image

$color = Imagecolorallocatealpha ($image _resized, 0, 0, 0, 127);

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

Imagefill ($image _resized, 0, 0, $color);

Restore Transparency Blending

Imagesavealpha ($image _resized, true);

}

}

Imagecopyresampled ($image _resized, $image, 0, 0, 0, 0, $final _width, $final _height, $width _old, $height _old);

if ($delete _original) {

if ($use _linux_commands)

EXEC (' rm '. $file);

Else

@unlink ($file);

}

Switch (Strtolower ($output)) {

Case ' Browser ':

$mime = Image_type_to_mime_type ($info [2]);

Header ("Content-type: $mime");

$output = NULL;

Break

Case ' file ':

$output = $file;

Break

Case ' return ':

return $image _resized;

Break

Default

Break

}

Switch ($info [2]) {

Case Imagetype_gif:

Imagegif ($image _resized, $output);

Break

Case IMAGETYPE_JPEG:

Imagejpeg ($image _resized, $output);

Break

Case Imagetype_png:

Imagepng ($image _resized, $output);

Break

Default

return false;

}

return true;

}