Imagick::sparseColorImage

(PECL imagick 2 >= 2.3.0, PECL imagick 3)

Imagick::sparseColorImageInterpolates colors

说明

public Imagick::sparseColorImage(int $SPARSE_METHOD, array $arguments, int $channel = Imagick::CHANNEL_DEFAULT): bool

Given the arguments array containing numeric values this method interpolates the colors found at those coordinates across the whole image using sparse_method. 此方法在Imagick基于ImageMagick 6.4.5以上版本编译时可用。

参数

SPARSE_METHOD

Refer to this list of sparse method constants

arguments

An array containing the coordinates. The array is in format array(1,1, 2,45)

channel

Provide any channel constant that is valid for your channel mode. To apply to more than one channel, combine channel constants using bitwise operators. 缺省为Imagick::CHANNEL_DEFAULT. 参考此 通道常数列表

返回值

成功时返回 true

错误/异常

错误时抛出 ImagickException。

范例

示例 #1 SPARSECOLORMETHOD_BARYCENTRIC Imagick::sparseColorImage()

<?php
function renderImageBarycentric2() {
$points = [
[
0.30, 0.10, 'red'],
[
0.10, 0.80, 'blue'],
[
0.70, 0.60, 'lime'],
[
0.80, 0.20, 'yellow'],
];
$imagick = createGradientImage(
400, 400,
$points,
\
Imagick::SPARSECOLORMETHOD_BARYCENTRIC
);
header("Content-Type: image/png");
echo
$imagick->getImageBlob();
}

?>

示例 #2 SPARSECOLORMETHOD_BILINEAR Imagick::sparseColorImage()

<?php
function renderImageBilinear() {
$points = [[0.30, 0.10, 'red'], [0.10, 0.80, 'blue'], [0.70, 0.60, 'lime'], [0.80, 0.20, 'yellow'],];
$imagick = createGradientImage(500, 500, $points, \Imagick::SPARSECOLORMETHOD_BILINEAR);
header("Content-Type: image/png");
echo
$imagick->getImageBlob();
}

?>

示例 #3 SPARSECOLORMETHOD_SPEPARDS Imagick::sparseColorImage()

<?php
function renderImageShepards() {
$points = [
[
0.30, 0.10, 'red'],
[
0.10, 0.80, 'blue'],
[
0.70, 0.60, 'lime'],
[
0.80, 0.20, 'yellow'],
];
$imagick = createGradientImage(600, 600, $points, \Imagick::SPARSECOLORMETHOD_SPEPARDS);
header("Content-Type: image/png");
echo
$imagick->getImageBlob();
}

?>

示例 #4 SPARSECOLORMETHOD_VORONOI Imagick::sparseColorImage()

<?php
function renderImageVoronoi() {
$points = [
[
0.30, 0.10, 'red'],
[
0.10, 0.80, 'blue'],
[
0.70, 0.60, 'lime'],
[
0.80, 0.20, 'yellow'],
];
$imagick = createGradientImage(500, 500, $points, \Imagick::SPARSECOLORMETHOD_VORONOI);
header("Content-Type: image/png");
echo
$imagick->getImageBlob();
}

?>

示例 #5 SPARSECOLORMETHOD_BARYCENTRIC Imagick::sparseColorImage()

<?php
function renderImageBarycentric() {
$points = [
[
0, 0, 'skyblue'],
[-
1, 1, 'skyblue'],
[
1, 1, 'black'],
];
$imagick = createGradientImage(600, 200, $points, \Imagick::SPARSECOLORMETHOD_BARYCENTRIC);
header("Content-Type: image/png");
echo
$imagick->getImageBlob();
}

?>

示例 #6 createGradientImage is used by other examples. Imagick::sparseColorImage()

<?php
function createGradientImage($width, $height, $colorPoints, $sparseMethod, $absolute = false) {

$imagick = new \Imagick();
$imagick->newImage($width, $height, "white");
$imagick->setImageFormat("png");

$barycentricPoints = array();

foreach (
$colorPoints as $colorPoint) {

if (
$absolute == true) {
$barycentricPoints[] = $colorPoint[0];
$barycentricPoints[] = $colorPoint[1];
}
else {
$barycentricPoints[] = $colorPoint[0] * $width;
$barycentricPoints[] = $colorPoint[1] * $height;
}

if (
is_string($colorPoint[2])) {
$imagickPixel = new \ImagickPixel($colorPoint[2]);
}
else if (
$colorPoint[2] instanceof \ImagickPixel) {
$imagickPixel = $colorPoint[2];
}
else{
$errorMessage = sprintf(
"Value %s is neither a string nor an ImagickPixel class. Cannot use as a color.",
$colorPoint[2]
);

throw new \
InvalidArgumentException(
$errorMessage
);
}

$red = $imagickPixel->getColorValue(\Imagick::COLOR_RED);
$green = $imagickPixel->getColorValue(\Imagick::COLOR_GREEN);
$blue = $imagickPixel->getColorValue(\Imagick::COLOR_BLUE);
$alpha = $imagickPixel->getColorValue(\Imagick::COLOR_ALPHA);

$barycentricPoints[] = $red;
$barycentricPoints[] = $green;
$barycentricPoints[] = $blue;
$barycentricPoints[] = $alpha;
}

$imagick->sparseColorImage($sparseMethod, $barycentricPoints);

return
$imagick;
}

?>

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User Contributed Notes 1 note

up
3
aehtyb[]gmail.com
6 years ago
For those curious how to use sparseColorImage() directly without the seperate createGradientImage() function.. here is the format of the array used:

Array (
[0]  => 0   // X1 (X coordinate value #1)
[1]  => 0   // Y1 (Y coordinate value #1)
[2]  => 1   // R (red value between 0 and 1)
[3]  => 0   // G (green value between 0 and 1)
[4]  => 0   // B (blue value between 0 and 1)
[5]  => 1   // A (alpha value between 0 and 1)
[6]  => 400 // X2
[7]  => 0   // Y2
[8]  => 0   // R
[9]  => 1   // G
[10] => 0   // B
[11] => 1   // A
[12] => 0   // X3
[13] => 400 // Y3
[14] => 1   // R
[15] => 1   // G
[16] => 0   // B
[17] => 1   // A
[18] => 400 // X4
[19] => 400 // Y4
[20] => 0   // R
[21] => 0   // G
[22] => 1   // B
[23] => 1   // A
)

<?php

$imagick
= new imagick();
$imagick->newImage(400,400,"white");
$imagick->setImageFormat("png");

$array = Array(0,0,1,0,0,1,400,0,0,1,0,1,0,400,1,1,0,1,400,400,0,0,1,1);
$imagick->sparseColorImage(imagick::SPARSECOLORMETHOD_BILINEAR,$array);
   
header("Content-Type: image/png");
echo
$imagick->getImageBlob();

?>
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