Syntax:bool Imagick::contrastStretchImage (float $black_point, float $white_point, int $channel = Imagick::CHANNEL_DEFAULT)
Parameters:This function takes three parameters as above and described below: - $black_point:this parameter contains a black point.
- $white_point:this parameter contains a white point.
- $channel:This parameter contains Imagick channel constants that provide any channel constant that is valid for channel mode. You can combine multiple channels using bitwise operators. The default channel constant is CHANNEL_DEFAULT.
Returned value:This function returns TRUE on success.The following programs illustrate function Imagick::contrastStretchImage()in PHP:Program 1:
// Create a new Imagick object
$imagick
=
new
Imagick (
’ https://media.engineerforengineer.org/wp-content/uploads/engineerforengineer-9.png ’
);
// Apply contrast line function()
$imagick
-> contrastStretchImage (10, 20);
header (
" Content-Type: image / png "
);
// Display the output image
echo
$imagick
-> getImageBlob();
?>
Output: Program 2:
// Create new Imagick object
$imagick
=
new
Imagick (
’ https://media.engineerforengineer.org/wp-content/uploads/engineerforengineer-9.png ’
);
// Apply contrast line function()
$imagick
-> contrastStretchImage (100, 50);
header (
" Content-Type: image / png "
);
// Display the output image
echo
$imagick
-> getImageBlob();
?>
Output: Program 3:
// Create new Imagick object
$imagick
=
new
Imagick (
’ https://media.engineerforengineer.org/wp-content/uploads/engineerforengineer-9.png ’
);
// Apply contrast line function()
$imagick
-> contrastStretchImage (5000, 100);
header (
" Content-Type: image / png "
);
// Display the output image
echo
$imagick
-> getImageBlob();
?>
Output: Link: https://www.php.net/manual/en/imagick.contraststretchimage.php