PHP | Gmagick setimagechanneldepth() Function

<?php
 
// Create new Gmagick object
$im = new Gmagick(
'https://media.geeksforgeeks.org/wp-content/uploads/geeksforgeeks-15.png');
 
// Using getImageChannelDepth function
// with red channel
echo "Before Set Channel depth: " . "</br>";
echo $im->getImageChannelDepth(Gmagick::CHANNEL_RED) . "</br>";
 
// Set channel Depth of CYAN and GREEN Channel
$im->setimagechanneldepth(Gmagick::CHANNEL_RED, 4);
 
echo "After Set Channel depth: " . "</br>";
echo $im->getImageChannelDepth(Gmagick::CHANNEL_RED) . "</br>";

?>

<?php 
 
$string = "Computer Science portal for Geeks!"; 
 
// Creating new image of above String 
// and add color
$im = new Gmagick(); 
$draw = new GmagickDraw(); 
 
// Fill the color in image 
$draw->setFillColor(new GmagickPixel('green')); 
 
// Set the text font size 
$draw->setFontSize(50); 
 
$metrix = $im->queryFontMetrics($draw, $string); 
$draw->annotation(0, 40, $string); 
$im->newImage($metrix['textWidth'], $metrix['textHeight'], 
        new GmagickPixel('white')); 
 
// Draw the image         
$im->drawImage($draw); 
$im->setImageFormat('jpeg'); 
 
// Using getImageChannelDepth function
// with red channel
echo "Before Set Channel depth: " . "</br>";
echo $im->getImageChannelDepth(Gmagick::CHANNEL_GREEN) . "</br>";
 
// Set channel Depth of Green Channel
$im->setimagechanneldepth(Gmagick::CHANNEL_GREEN, 8);
 
echo "After Set Channel depth: " . "</br>";
echo $im->getImageChannelDepth(Gmagick::CHANNEL_GREEN) . "</br>";

?>