If you're having trouble with white backgrounds turning black when converting PDFs to other formats, you need to use this function with Imagick::ALPHACHANNEL_REMOVE as the parameter (this is not currently on the constants page, but it exists in PHP 7.2) to remove the alpha channel.
<?php
$im->setImageAlphaChannel(Imagick::ALPHACHANNEL_REMOVE );
?>
Imagick::setImageAlphaChannel
(No version information available, might only be in Git)
Imagick::setImageAlphaChannel — Sets image alpha channel
說明
bool Imagick::setImageAlphaChannel
( int
$mode
)
Activate or deactivate image alpha channel. The mode
is one of the Imagick::ALPHACHANNEL_* constants.
此方法在Imagick基於ImageMagick 6.3.8以上版本編譯時可用。
參數
-
mode -
One of the
Imagick::ALPHACHANNEL_*constants
回傳值
成功時回傳 TRUE。
錯誤/例外
錯誤時拋出 ImagickException。
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simonjjarrett at gmail dot com ¶
4 years ago
