PHP | ImagickPixelIterator newPixelRegionIterator() Function

The ImagickPixelIterator::newPixelRegionIterator() function is an inbuilt function in PHP which is used to get a new pixel iterator from a specific region from the imagick wand.

Syntax:

bool ImagickPixelIterator::newPixelRegionIterator( Imagick $wand,
         int $x, int $y, int $columns, int $rows )

Parameters: This function accept five parameters as mentioned above and described below:

• $wand: It specifies the imagick wand.
• $x: It specifies the x-coordinate.
• $y: It specifies the y-coordinate.
• $columns: It specifies the number of columns.
• $rows: It specifies the numbers of rows.

Return Value: This function returns TRUE on success.

Exceptions: This function throws ImagickException on error.

Below programs illustrate the ImagickPixelIterator::newPixelRegionIterator() function in PHP:

Program 1: This program drawing a square on a blank image.

<?php

// Create a new imagick object
$imagick = new Imagick();

// Create a image on imagick object
$imagick->newImage(800, 250, 'black');

// Create a new ImagickPixelIterator instance
$imageIterator = new ImagickPixelIterator();

// Get the pixels from a image region
$imageIterator->newPixelRegionIterator($imagick, 40, 30, 200, 200);

// Loop through pixel rows
foreach ($imageIterator as $row => $pixels) {

    foreach ($pixels as $column => $pixel) {

        // Set the color of each pixel
        $pixel->setColor('red');
    }

    // Sync the iterator after each iteration
    $imageIterator->syncIterator();
}

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

Output:

Program 2: This program drawing a rectangle on a png image.

<?php

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

// Create a new ImagickPixelIterator instance
$imageIterator = new ImagickPixelIterator();

// Get the pixels from a image region
$imageIterator->newPixelRegionIterator($imagick, 40, 100, 1200, 20);

// Loop through pixel rows
foreach ($imageIterator as $row => $pixels) {

    foreach ($pixels as $column => $pixel) {

        // Set the color of each pixel
        $pixel->setColor('#62AC45');
    }

    // Sync the iterator after each iteration
    $imageIterator->syncIterator();
}

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

Output:

Reference: https://www.php.net/manual/en/imagickpixeliterator.newpixelregioniterator.php