PHP | Imagick sparseColorImage() Function

The Imagick::sparseColorImage() function is an inbuilt function in PHP which is used to interpolate the colors across the whole image.

Syntax:

bool Imagick::sparseColorImage( int $SPARSE_METHOD, array $arguments, int $channel )

Parameters: This function accepts three parameters as mentioned above and described below:

• $SPARSE_METHOD: It specifies an integer corresponding to one of SPARSECOLORMETHOD constants. List of SPARSECOLORMETHOD constants are given below:
  • imagick::SPARSECOLORMETHOD_UNDEFINED (0)
  • imagick::SPARSECOLORMETHOD_BARYCENTRIC (1)
  • imagick::SPARSECOLORMETHOD_BILINEAR (7)
  • imagick::SPARSECOLORMETHOD_POLYNOMIAL (8)
  • imagick::SPARSECOLORMETHOD_SPEPARDS (16)
  • imagick::SPARSECOLORMETHOD_VORONOI (18)
• $arguments: It specifies the coordinates.
• $channel (Optional): It specifies any channel constant that is valid for your channel mode. To apply more than one channel, combine channel constants using bit-wise operators. Its default value is Imagick::CHANNEL_DEFAULT.

Return Value: This function returns TRUE on success.

Below programs illustrate the Imagick::sparseColorImage() function in PHP:

Program 1:

<?php

// Create a new imagick object
$imagick = new Imagick(
'https://media.geeksforgeeks.org/wp-content/uploads/geeksforgeeks-13.png');

$array = array(0, 0, 1, 0, 0, 1, 900, 0, 0, 1,
               0, 1, 0, 1, 100, 1, 0, 70, 400,
               90, 0, 0, 1, 1);

// Apply the sparseColorImage() function
$imagick->sparseColorImage(imagick::SPARSECOLORMETHOD_BILINEAR, $array);

// Show the output
header("Content-Type: image/png");
echo $imagick->getImageBlob();
?>

Output:

Program 2:

<?php

// Create a new imagick object
$imagick = new Imagick(
'https://media.geeksforgeeks.org/wp-content/uploads/geeksforgeeks-13.png');

$array = array(0, 0, 1, 0, 0, 1, 78, 0, 0, 1,
               0, 1, 0, 1, 10, 1, 0, 20, 400,
               90, 0, 0, 1, 1);

// Apply the sparseColorImage() function
$imagick->sparseColorImage(imagick::SPARSECOLORMETHOD_BARYCENTRIC, $array);

// Show the output
header("Content-Type: image/png");
echo $imagick->getImageBlob();
?>

Output:

Reference: https://www.php.net/manual/en/imagick.sparsecolorimage.php