我想获取一个PNG文件并使其透明度达到50%。我怎么能用PHP做到这一点?我想用它作为水印,我已经可以在图像上得到它,但现在我需要使水印透明。
答案 0 :(得分:1)
将一个类应用于图像
<style>
.opacity-50 {
opacity: 0.5;
filter: alpha(opacity=50);
}
</style>
<img class="opacity-50" src="filename.png">
答案 1 :(得分:1)
使用PHP,您可以通过创建掩码使用Imagick来执行此操作。以下示例来自this tutorial。
<?php
// Create objects
$image = new Imagick('image.png');
$watermark = new Imagick();
$mask = new Imagick();
$draw = new ImagickDraw();
// Define dimensions
$width = $image->getImageWidth();
$height = $image->getImageHeight();
// Create some palettes
$watermark->newImage($width, $height, new ImagickPixel('grey30'));
$mask->newImage($width, $height, new ImagickPixel('black'));
// Watermark text
$text = 'Copyright';
// Set font properties
$draw->setFont('Arial');
$draw->setFontSize(20);
$draw->setFillColor('grey70');
// Position text at the bottom right of the image
$draw->setGravity(Imagick::GRAVITY_SOUTHEAST);
// Draw text on the watermark palette
$watermark->annotateImage($draw, 10, 12, 0, $text);
// Draw text on the mask palette
$draw->setFillColor('white');
$mask->annotateImage($draw, 11, 13, 0, $text);
$mask->annotateImage($draw, 10, 12, 0, $text);
$draw->setFillColor('black');
$mask->annotateImage($draw, 9, 11, 0, $text);
// This is needed for the mask to work
$mask->setImageMatte(false);
// Apply mask to watermark
$watermark->compositeImage($mask, Imagick::COMPOSITE_COPYOPACITY, 0, 0);
// Overlay watermark on image
$image->compositeImage($watermark, Imagick::COMPOSITE_DISSOLVE, 0, 0);
// Set output image format
$image->setImageFormat('png');
// Output the new image
header('Content-type: image/png');
echo $image;