Use PHP to convert PNG to JPG with compression?

Do this to convert safely a PNG to JPG with the transparency in white.

$image = imagecreatefrompng($filePath);$bg = imagecreatetruecolor(imagesx($image), imagesy($image));imagefill($bg, 0, 0, imagecolorallocate($bg, 255, 255, 255));imagealphablending($bg, TRUE);imagecopy($bg, $image, 0, 0, 0, 0, imagesx($image), imagesy($image));imagedestroy($image);$quality = 50; // 0 = worst / smaller file, 100 = better / bigger file imagejpeg($bg, $filePath . ".jpg", $quality);imagedestroy($bg);

Be careful of what you want to convert. JPG doesn't support alpha-transparency while PNG does. You will lose that information.

To convert, you may use the following function:

// Quality is a number between 0 (best compression) and 100 (best quality)function png2jpg($originalFile, $outputFile, $quality) {    $image = imagecreatefrompng($originalFile);    imagejpeg($image, $outputFile, $quality);    imagedestroy($image);}

This function uses the imagecreatefrompng() and the imagejpeg() functions from the GD library.

This is a small example that will convert 'image.png' to 'image.jpg' at 70% image quality:

<?php$image = imagecreatefrompng('image.png');imagejpeg($image, 'image.jpg', 70);imagedestroy($image);?>

Hope that helps