imagepng()是PHP中的一個(gè)內(nèi)置函數(shù),用于在瀏覽器或文件中顯示圖像。該函數(shù)的主要用途是在瀏覽器中查看圖像,將任何其他圖像類型轉(zhuǎn)換為PNG,并對(duì)圖像應(yīng)用過(guò)濾器。
語(yǔ)法:
bool imagepng( resource $image, int $to, int $quality, int $filters)
參數(shù):該函數(shù)接受上述和以下所述的三個(gè)參數(shù):
$image:指定要處理的圖像資源。
$to (Optional):指定保存文件的路徑。
$quality (Optional):指定圖像的質(zhì)量。
$filters (Optional):指定應(yīng)用于圖像的過(guò)濾器,這些過(guò)濾器有助于減小圖像大小。
返回值:如果成功,此函數(shù)返回TRUE,否則返回FALSE。
示例1:
<?php // 從PNG URL加載圖像 $im = imagecreatefrompng('http://www.miracleart.cn/static/images/logo.png'); // 使用imagepng()函數(shù)在瀏覽器中查看加載的圖像 header('Content-type: image/png'); imagepng($im); imagedestroy($im); ?>
示例2:使用過(guò)濾器
<?php // 從PNG URL加載圖像 $im = imagecreatefrompng('http://www.miracleart.cn/static/images/logo.png'); // 將圖像另存為image1.png imagepng($im, 'image1.png'); // 將圖像保存為image2.png,并使用所有過(guò)濾器禁用大小壓縮 imagepng($im, 'image2.png', null, PNG_ALL_FILTERS); imagedestroy($im); ?>
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