imagepalettetotruecolor
(PHP 5 >= 5.5.0, PHP 7, PHP 8)
imagepalettetotruecolor — Converts a palette based image to true color
說明
Converts a palette based image, created by functions like imagecreate() to a true color image, like imagecreatetruecolor().
返回值
   Returns true if the convertion was complete, or if the source image already 
   is a true color image, otherwise false is returned.
  
更新日誌
| 版本 | 說明 | 
|---|---|
| 8.0.0 | imageexpects a GdImage
  instance now; previously, a resource was expected. | 
範例
示例 #1 Converts any image object to true color
<?php
// Backwards compatiblity
if(!function_exists('imagepalettetotruecolor'))
{
    function imagepalettetotruecolor(&$src)
    {
        if(imageistruecolor($src))
        {
            return(true);
        }
        $dst = imagecreatetruecolor(imagesx($src), imagesy($src));
        imagecopy($dst, $src, 0, 0, 0, 0, imagesx($src), imagesy($src));
        imagedestroy($src);
        $src = $dst;
        return(true);
    }
}
// Helper closure
$typeof = function() use($im)
{
    echo 'typeof($im) = ' . (imageistruecolor($im) ? 'true color' : 'palette'), PHP_EOL;
};
// Create a palette based image
$im = imagecreate(100, 100);
$typeof();
// Convert it to true color
imagepalettetotruecolor($im);
$typeof();
// Free the memory
imagedestroy($im);
?>
以上例程會輸出:
typeof($im) = palette typeof($im) = true color
參見
- imagecreatetruecolor() - 新建一個真彩色影象
- imageistruecolor() - 檢查影象是否為真彩色影象