Imagick::getImagePixelColor()
(PECL imagick 2.0.0)
Returns the color of the specified pixel
说明
Imagick::getImagePixelColor(int $x,int $y): ImagickPixel
Returns the color of the specified pixel.
参数
- $x
The x-coordinate of the pixel
- $y
The y-coordinate of the pixel
返回值
Returns an ImagickPixel instance for the color at the coordinates given.
错误/异常
错误时抛出 ImagickException。
I'm sure there are a lot of people like me who have been wondering, "How you manage to produce a human readable output of this operation?" <?php $image = new Imagick('testimage.jpg'); $x = 1; $y = 1; $pixel = $image->getImagePixelColor($x, $y); ?> If you try to print an output of the $pixel object, you get nothing. You have to use one of the ImagickPixel operations to get back a value. You can do either of the following: <?php $colors = $pixel->getColor(); print_r($colors); // produces Array([r]=>255,[g]=>255,[b]=>255,[a]=>1); $pixel->getColorAsString(); // produces rgb(255,255,255); ?> The place where I was getting hung up was how to get the data that was captured in the Imagick::getImagePixelColor operation into an ImagickPixel object. I was trying to find ways of passing the value to a newly instantiated ImagickPixel object. Well, it appears that once you've captured your color data using Imagick::getImagePixelColor, what's returned IS an ImagickPixel object! As a further note, you do not need to convert this to a human readable format if you just want to take a color sample at a single point on your image to plug into another operation. For example, if you wanted to perform a flood fill effect on a certain color you could plug in the instance of the ImagickPixel object directly. The following fill perform a flood fill effect at coordinates 1,1 on your image using Green as the fill color and the color sampled at 1,1 as the target color to fill. <?php $hexcolor = '#00ff00'; $fuzz = '4000'; $x = 1; $y = 1; $pixel = $image->getImagePixelColor($x, $y); $image->floodfillPaintImage($hexcolor, $fuzz, $pixel, $x, $y, false); ?>