Mask images with a generated Imagick image

Question

I need to know how it is possible to mask any square image using Imagick. Here is the code I have so far, but the image just doesn't get masked properly:

Get the image

$srcFile = 'filename.png';
$image = new Imagick($srcFile);

Crop the image to square

$d = $image->getImageGeometry();
$src_width = $d['width']; 
$src_height = $d['height'];
$thumbSize = min(max($src_width, $src_height), abs($thumbSize));        
if ($src_width < $src_height) {
    $image->cropImage($src_width, $src_width, 0, (($src_height - $src_width)/2));
} else {
    $image->cropImage($src_height, $src_height, (($src_width - $src_height)/2), 0);
}

Resize the image

$image->thumbnailImage($thumbSize, $thumbSize, 1);

Crop / Mask the image with the bezier shape

$image->compositeImage(bezier($thumbSize, $thumbSize), Imagick::COMPOSITE_COPYOPACITY, 0, 0);

The bezier function creates a shape looking like this:

function bezier($width, $height) {
    $fillColor = "#000";
    $draw = new ImagickDraw();

Fill the unmasked part with black color

    $fillColor = new ImagickPixel($fillColor);
    $draw->setFillColor($fillColor);
    $smoothPointsSet = [
        [
            ['x' => 0.0 * $width, 'y' => 0.5 * $width],
            ['x' => 0.0 * $width, 'y' => 0.905 * $width],
            ['x' => 0.095 * $width, 'y' => 1.0 * $width],
            ['x' => 0.5 * $width, 'y' => 1.0 * $width]
        ], [
            ['x' => 0.5 * $width, 'y' => 1.0 * $width],
            ['x' => 0.905 * $width, 'y' => 1.0 * $width],
            ['x' => 1.0 * $width, 'y' => 0.905 * $width],
            ['x' => 1.0 * $width, 'y' => 0.5 * $width]
        ], [
            ['x' => 1.0 * $width, 'y' => 0.5 * $width],
            ['x' => 1.0 * $width, 'y' => 0.095 * $width],
            ['x' => 0.905 * $width, 'y' => 0.0 * $width],
            ['x' => 0.5 * $width, 'y' => 0.0 * $width]
        ], [
            ['x' => 0.5 * $width, 'y' => 0.0 * $width],
            ['x' => 0.095 * $width, 'y' => 0.0 * $width],
            ['x' => 0.0 * $width, 'y' => 0.095 * $width],
            ['x' => 0.0 * $width, 'y' => 0.5 * $width]
        ]
    ];

    foreach ($smoothPointsSet as $points) {
        $draw->bezier($points);
    }

The bezier points don't fill a square in the middle so fill it manually

    $points = [
        ['x' => $width * 0.5, 'y' => 0.0],
        ['x' => 0.0, 'y' => $height * 0.5],
        ['x' => $width * 0.5, 'y' => $height],
        ['x' => $width, 'y' => $height * 0.5]
    ];
    $draw->polygon($points);

Copy the drawer image to a new transparent Imagick image

    $imagick = new Imagick();
    $imagick->newImage($width, $width, "none");

From here on I have experimented with various properties. I didn't get any satisfying result - the image almost always doesn't get masked.

    #$imagick->setImageAlphaChannel(Imagick::ALPHACHANNEL_SHAPE);
    #$imagick->setImageFormat("png");

    $imagick->drawImage($draw);

    #$imagick->setImageMatte(false);

    return $imagick;
}

I would be very glad if I could know where the problem lies and how to fix it. I found various answers on SO that didn't work for me:

Use $dude->setImageMatte(1); Using a transparent PNG as a clip mask

Use $base->compositeImage($mask, Imagick::COMPOSITE_DSTIN, 0, 0, Imagick::CHANNEL_ALPHA); How to use Imagick to merge and mask images?

Unfortunately I couldn't resolve the problem.

Answer 1

The problem was that images were stored as JPEG so the transparent part became black. This is the code I used:

$mask = bezier($thumbSize, $thumbSize);

// Copy opacity mask
if ($image->getImageMatte()) {
    $image->compositeImage($mask, Imagick::COMPOSITE_DSTIN, 0, 0, Imagick::CHANNEL_ALPHA);
} else {
    $image->compositeImage($mask, Imagick::COMPOSITE_COPYOPACITY, 0, 0);
}

$image->setImageBackgroundColor(new ImagickPixel('white'));
#$image->setImageAlphaChannel(Imagick::ALPHACHANNEL_DEACTIVATE);
$image = $image->flattenImages();

In function bezier:

$imagick = new Imagick();
$imagick->newImage($width, $width, "none");
$imagick->setImageBackgroundColor(new ImagickPixel('transparent'));
#$imagick->setImageAlphaChannel(Imagick::ALPHACHANNEL_SHAPE);
$imagick->setImageFormat("png");

//Render the draw commands in the ImagickDraw object 
//into the image.
$imagick->drawImage($draw);
$imagick->negateImage(FALSE);


return $imagick;