识别图像的像素 RGB 代码，并使用 PHP 替换为新的 RGB 代码 - Identify pixel RGB code of an Image and replace with new RGB code using PHP

Identify pixel RGB code of an Image and replace with new RGB code using PHP

我有一个存储在数据库中的图像，我想识别特定像素的RGB代码。我想使用 PHP 将其替换为我的新 RGB 值。任何人都可以帮我提供有效代码吗？

<?
    //create an image resource depending on your image type. http://php.net/manual-lookup.php?pattern=imagecreatefrom*&scope=quickref
    $imgh = imagecreatefrompng("/path/to/png/image.png");
    $xpos = 10;
    $ypos = 14;
    //Get the color information of the pixil you want  http://php.net/manual/en/function.imagecolorat.php
    $rgb = imagecolorat($imgh, $xpos, $ypos);
    //Convert to RGB
    $r = ($rgb >> 16) & 0xFF;
    $g = ($rgb >> 8) & 0xFF;
    $b = $rgb & 0xFF;
    //Do whatever you need to do to determine new rgb.
    $new_r = 12;
    $new_g = 58;
    $new_b = 200;
    //Create a new color to apply to image.  http://php.net/manual/en/function.imagecolorallocate.php
    $new_color = imagecolorallocate ( $imgh , $new_r , $new_g , $new_b );
    //replace pixel with new color  http://php.net/imagesetpixel
    imagesetpixel($imgh,$xpos,$ypos,$new_color);
    //Save image to new filename.  http://www.php.net/manual/en/function.imagepng.php
    imagepng($imgh,'/path/to/png/new.png');
?>