Phalcon PNG to JPG and remove transparent background image - php

Question

I'm using Phalcon PHP Phalcon\Images\Adapter\GD and I have a problem with the PNG to JPG.
When I upload a PNG image on my server, I resize this image, I set the background color in white with the background method $myImage->background('#FFFFFF') but this background is now black... I don't understand why and after I split the extension .PNG and I add .JPG.
How can I do to set the background color image to white ?

Answer 1

Try this it worked for me :
function img_resize($file,$width=0,$height=0,$proportional=false,$output='file' ) {
if ( $height <= 0 && $width <= 0 ) return false;
# Setting defaults and meta
$info= getimagesize($file);
$image= '';
$final_width= 0;
$final_height= 0;
list($width_old, $height_old) = $info;
# Calculating proportionality
if ($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;
}
# Loading image to memory according to type
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;
}
# This is the resizing/resampling/transparency-preserving magic
$image_resized = imagecreatetruecolor( $final_width, $final_height );
if ( ($info[2] == IMAGETYPE_GIF) || ($info[2] == IMAGETYPE_PNG) ) {
$transparency = imagecolortransparent($image);
if ($transparency >= 0) {
$transparent_color = imagecolorsforindex($image, $trnprt_indx);
$transparency = imagecolorallocate($image_resized, $trnprt_color['red'], $trnprt_color['green'], $trnprt_color['blue']);
imagefill($image_resized, 0, 0, $transparency);
imagecolortransparent($image_resized, $transparency);
}
elseif ($info[2] == IMAGETYPE_PNG) {
imagealphablending($image_resized, false);
$color = imagecolorallocatealpha($image_resized, 0, 0, 0, 127);
imagefill($image_resized, 0, 0, $color);
imagesavealpha($image_resized, true);
}
}
imagecopyresampled($image_resized, $image, 0, 0, 0, 0, $final_width, $final_height, $width_old, $height_old);
# Preparing a method of providing result
switch ( strtolower($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;
}
# Writing image according to type to the output destination
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;
}
Call function like below :
$image = new Phalcon\Image\Adapter\GD(YOUR_IMAGE_PATH);
$a=img_resize($image->getRealpath(),$image->getWidth(),$image->getHeight());
Some code might not necessary for you.