Actually it does seem to work just not the way expected perhaps.
Looking at the fuzz option on ImageMagick's site (http://www.imagemagick.org/script/command-line-options.php#fuzz), "The distance can be in absolute intensity units or, by appending % as a percentage of the maximum possible intensity (255, 65535, or 4294967295)."
As it requires a float, the percentage value won't work so it actually one of the max intensity values. In my case, the images I was working with seemed to have max intensity values of 65535. So a fuzz of 6500, for roughly 10%, seemed to do the trick.
The part that might be problematic though is how do you determine the max intensity of a color/image? Using a static 6500 would be fine until I would have to convert an image with a max intensity other than 65535. If it's 255 it would wipe the entire image. Or fall far short on the fuzz with the larger value.
Imagick::paintTransparentImage
(PECL imagick 2.0.0)
Imagick::paintTransparentImage — Changes any pixel that matches color with the color defined by fill
說明
Changes any pixel that matches color with the color defined by fill.
參數
-
target -
Change this target color to specified opacity value within the image.
-
alpha -
The level of transparency: 1.0 is fully opaque and 0.0 is fully transparent.
-
fuzz -
The fuzz member of image defines how much tolerance is acceptable to consider two colors as the same.
回傳值
成功時回傳 TRUE。
錯誤/例外
錯誤時拋出 ImagickException。
更新日誌
| 版本 | 說明 |
|---|---|
| 2.1.0 | Now allows a string representing the color as the first parameter. Previous versions allow only an ImagickPixel object. |
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User Contributed Notes 3 notes
Anonymous ¶
15 years ago
quickshiftin at gmail dot com ¶
9 years ago
Have a look at this thread on Stackoverflow for the answer regarding how to determine the max intensity of an image.
http://stackoverflow.com/questions/26239130/determine-max-possible-intensity-of-image/26240656#26240656
In short here is the code to make the $fuzz parameter behave more like you would expect (it now represents a percentage between 0-100). The $fuzz value should now be a float between 0 and 1.
class SaneImagick extends Imagick
{
public function paintTransparentImage($target, $alpha, $fuzz)
{
$iQuantumDepth = pow(2, $this->getQuantumDepth()['quantumDepthLong']);
return parent::paintTransparentImage($target, $alpha, $fuzz * $iQuantumDepth);
}
}
alain at ocarina dot fr ¶
12 years ago
The fuzz is just working well in a range of 0 to 65535.
I suggest you to try to move fuzz on a color spectrum image.
1/ Get a color spectrum ( Google Image has a lot )
2/ Try this code :
<?php
function fuzzTest($source, $target, $fuzz) {
// Loads image
$im = new Imagick($source);
// Resizes images to make them easily comparable
$im->resizeImage(320, 240, Imagick::FILTER_LANCZOS, 1, true);
// Apply fuzz
$im->paintTransparentImage($im->getImagePixelColor(0, 0), 0, $fuzz);
// Writes image
$im->setImageFormat('png');
$im->writeImage($target);
$im->destroy();
return true;
}
for ($i = 0; ($i <= 10); $i++) {
fuzzTest('spectrum.png', "test_{$i}.png", (6553.5 * $i));
echo '<img src="test_' . $i . '.png" /> ';
}
?>
