PHP - 使用Imagick将所有图像转换为jpg - 质量差

Question

I found more topics from this web site about quality with Imagick but nothing help me... I have to save all images as JPG. I created this script:

$image_url = 'http://limuzynamercedes.pl/wp-content/uploads/2014/06/3.png';
$image_code = file_get_contents($image_url);

$img = new Imagick();
$img -> readImageBlob($image_code);
$img->setResolution(300, 300);
$d = $img->getImageGeometry(); 
$img->cropImage($d['width'],($d['height']-120), 0,0);
$img->setImageFormat('jpeg');
$img->setImageCompression(imagick::COMPRESSION_JPEG); 
$img->setCompressionQuality(100); 
$img->writeImage('read.jpg');
$img->clear();

echo '<img src="read.jpg?'.time().'">';exit;

Here is original image: http://limuzynamercedes.pl/wp-content/uploads/2014/06/3.png and here is image which was converted by my script: http://s5.ifotos.pl/img/demo1jpg_saeaxqx.jpg

Where is a problem? Why this image is always convert in bad quality?

Thanks.

Answer 1

The image is not in "bad quality" (there is no blurry areas found), but the difference between 2 images is caused by transparent PNG to JPG conversion.

Before you crop the image, add these two lines:

// set background to white (Imagick doesn't know how to deal with transparent background if you don't instruct it)
$img->setImageBackgroundColor(new ImagickPixel('white'));

// flattens multiple layers
$img = $img->mergeImageLayers(Imagick::LAYERMETHOD_FLATTEN);