Imagick::setImageAlphaChannel

    (PECL imagick 2 >= 2.1.0, PECL imagick 3)

    Imagick::setImageAlphaChannel — Sets image alpha channel

    Descrizione

    public Imagick::setImageAlphaChannel(int $mode): bool

    Activate or deactivate image alpha channel. The mode is one of the Imagick::ALPHACHANNEL_* constants. Questo metodo è disponibile se Imagick è stato compilato con ImageMagick versione 6.3.8 o successive.

    Elenco dei parametri

    mode

    One of the Imagick::ALPHACHANNEL_* constants

    Valori restituiti

    Restituisce true in caso di successo.

    Errori/Eccezioni

    Lancia una ImagickException in caso di errore.

    Vedere anche:

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    User Contributed Notes 1 note

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    simonjjarrett at gmail dot com
    4 years ago
    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 );
    ?>
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