$image = "[...]"; //binary string containing PNG image $file = fopen('image.tmp', 'wb'); fputs($file, $image); fclose($file); $image = new Imagick('PNG:image.tmp'); $image->thumbnailImage($width, $height); $image->setImageFormat('jpg'); $image->setCompressionQuality(97); $image->writeImage('image.jpg');
The above doesn't work and gives me a black image for this image. When doing instead
[...] $image->setImageFormat('png'); $image->setCompressionQuality(97); $image->writeImage('image.png');
all is fine again. I think it has to do something with transparent background, which isn't available in JPG format. Can anyone help to solve this (imagick isn't documented very well, so I don't know how to help myself).
Found a solution:
$white=new Imagick(); $white->newImage($width, $height, "white"); $white->compositeimage($image, Imagick::COMPOSITE_OVER, 0, 0); $white->setImageFormat('jpg'); $white->writeImage('image.jpg');
Another way to convert transparent png to jpg, as mentioned in Imagick::flattenImages:
$im = new Imagick('image.png'); $im->setImageBackgroundColor('white'); $im->flattenImages(); // This does not do anything. $im = $im->flattenImages(); // Use this instead. $im->setImageFormat('jpg'); $im->writeImage('image.jpg');
You can use setBackgroundColor to set the default background color to something else than black. The PNG transparency will be replaced by the background color when saving to JPG.
Edit: Use it like so:
$img->setBackgroundColor(new ImagickPixel('#FFFFFF'));
Try adding $image->setBackgroundColor(0xFFFFFF); after $image = new Imagick('PNG:image.tmp');
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