/**
* Dither by applying a threshold map.
*
* @param Image $image
*
* @return Image
*/
private function ordered($image)
{
// Localize vars
$width = $image->getWidth();
$height = $image->getHeight();
$thresholdMap = array(array(15, 135, 45, 165), array(195, 75, 225, 105), array(60, 180, 30, 150), array(240, 120, 210, 90));
// Loop using image1
$pixelIterator = $image->getCore()->getPixelIterator();
foreach ($pixelIterator as $y => $rows) {
/* Loop through pixel rows */
foreach ($rows as $x => $px) {
/* Loop through the pixels in the row (columns) */
/**
* @var $px \ImagickPixel */
$rgba = $px->getColor();
$gray = round($rgba['r'] * 0.3 + $rgba['g'] * 0.59 + $rgba['b'] * 0.11);
$threshold = $thresholdMap[$x % 4][$y % 4];
$oldPixel = ($gray + $threshold) / 2;
if ($oldPixel <= 127) {
// Determine if black or white. Also has the benefit of clipping excess value
$newPixel = 0;
} else {
$newPixel = 255;
}
// Current pixel
$px->setColor("rgb({$newPixel},{$newPixel},{$newPixel})");
}
$pixelIterator->syncIterator();
/* Sync the iterator, this is important to do on each iteration */
}
$type = $image->getType();
$file = $image->getImageFile();
$image = $image->getCore();
return new Image($image, $file, $width, $height, $type);
// Create new image with updated core
}
/**
* Resize helper function.
*
* @param Image $image
* @param int $newWidth
* @param int $newHeight
*
* @return self
* @throws \Exception
*/
private function _resize(&$image, $newWidth, $newHeight)
{
if ('GIF' == $image->getType()) {
// Animated image. Eg. GIF
$imagick = $image->getCore()->coalesceImages();
foreach ($imagick as $frame) {
$frame->resizeImage($newWidth, $newHeight, \Imagick::FILTER_BOX, 1, false);
$frame->setImagePage($newWidth, $newHeight, 0, 0);
}
// Assign new image with frames
$image = new Image($imagick->deconstructImages(), $image->getImageFile(), $newWidth, $newHeight, $image->getType());
} else {
// Single frame image. Eg. JPEG, PNG
$image->getCore()->resizeImage($newWidth, $newHeight, \Imagick::FILTER_LANCZOS, 1, false);
// Assign new image
$image = new Image($image->getCore(), $image->getImageFile(), $newWidth, $newHeight, $image->getType());
}
}
/**
* @param Image $image
*
* @return Image
*/
public function apply($image)
{
$pixels = array();
$finalPx = array();
// Localize vars
$width = $image->getWidth();
$height = $image->getHeight();
// Loop
$pixelIterator = $image->getCore()->getPixelIterator();
foreach ($pixelIterator as $y => $rows) {
/* Loop through pixel rows */
foreach ($rows as $x => $px) {
/* Loop through the pixels in the row (columns) */
// row 0
if ($x > 0 and $y > 0) {
$matrix[0][0] = $this->getColor($px, $pixels, $x - 1, $y - 1);
} else {
$matrix[0][0] = $this->getColor($px, $pixels, $x, $y);
}
if ($y > 0) {
$matrix[1][0] = $this->getColor($px, $pixels, $x, $y - 1);
} else {
$matrix[1][0] = $this->getColor($px, $pixels, $x, $y);
}
if ($x + 1 < $width and $y > 0) {
$matrix[2][0] = $this->getColor($px, $pixels, $x + 1, $y - 1);
} else {
$matrix[2][0] = $this->getColor($px, $pixels, $x, $y);
}
// row 1
if ($x > 0) {
$matrix[0][1] = $this->getColor($px, $pixels, $x - 1, $y);
} else {
$matrix[0][1] = $this->getColor($px, $pixels, $x, $y);
}
if ($x + 1 < $width) {
$matrix[2][1] = $this->getColor($px, $pixels, $x + 1, $y);
} else {
$matrix[2][1] = $this->getColor($px, $pixels, $x, $y);
}
// row 1
if ($x > 0 and $y + 1 < $height) {
$matrix[0][2] = $this->getColor($px, $pixels, $x - 1, $y + 1);
} else {
$matrix[0][2] = $this->getColor($px, $pixels, $x, $y);
}
if ($y + 1 < $height) {
$matrix[1][2] = $this->getColor($px, $pixels, $x, $y + 1);
} else {
$matrix[1][2] = $this->getColor($px, $pixels, $x, $y);
}
if ($x + 1 < $width and $y + 1 < $height) {
$matrix[2][2] = $this->getColor($px, $pixels, $x + 1, $y + 1);
} else {
$matrix[2][2] = $this->getColor($px, $pixels, $x, $y);
}
$edge = $this->convolve($matrix);
$edge = intval($edge / 2);
if ($edge > 255) {
$edge = 255;
}
/**
* @var \ImagickPixel $px Current pixel.
*/
$finalPx[] = $edge;
// R
$finalPx[] = $edge;
// G
$finalPx[] = $edge;
// B
}
$pixelIterator->syncIterator();
/* Sync the iterator, this is important to do on each iteration */
}
$new = new \Imagick();
$new->newImage($width, $height, new \ImagickPixel('black'));
/* Import the pixels into image.
width * height * strlen("RGB") must match count($pixels) */
$new->importImagePixels(0, 0, $width, $height, "RGB", \Imagick::PIXEL_CHAR, $finalPx);
$type = $image->getType();
$file = $image->getImageFile();
return new Image($new, $file, $width, $height, $type);
// Create new image with updated core
}
