Convert PNG to JPG and set transparent background to white with ImageMagick and PHP

Question

How can I use ImageMagick (with the php extension) to set the transparent background to white when converting an image from PNG to JPEG?

Answer 1

At time of writing, you have not specified which extension you are using, but if you were using the commandline, the command would be:

convert image.png -background white -flatten -alpha off image.jpg 

More information can be found on the Masking Usage documentation.

Using IMagick for instance, I think you could do this as follows:

(totally untested, never used IMagick and don't have it installed to test)

$image = new IMagick('image.png');  $flattened = new IMagick(); $flattened->newImage($image->getImageWidth(), $image->getImageHeight(), new ImagickPixel("white"));  $flattened->compositeImage($image, imagick::COMPOSITE_OVER, 0, 0);  $flattened->setImageFormat("jpg"); $flattened->writeImage('image.jpg');  $image->clear(); $image->destroy(); $flattened->clear(); $flattened->destroy(); 

Answer 2

If you are using the Imagick extension:

<?php // load the source transparent png $i = new IMagick('image.png');  // set the background to white // you can also use 'rgb(255,255,255)' in place of 'white' $i->setImageBackgroundColor(new ImagickPixel('white'));  // flattens multiple layers $i = $i->flattenImages();  // the output format $i->setImageFormat('jpg');  // save to disk $i->writeImage('image.jpg');  // and/or output directly // header('Content-Type: '.$i->getFormat()); // echo $i->getImageBlob();  // cleanup $i->clear(); $i->destroy();