imagepalettetotruecolor
(PHP 5 >= 5.5.0, PHP 7, PHP 8)
imagepalettetotruecolor — Converts a palette based image to true color
说明
imagepalettetotruecolor
( GdImage
$image
) : boolConverts a palette based image, created by functions like imagecreate() to a true color image, like imagecreatetruecolor().
返回值
Returns true
if the convertion was complete, or if the source image already
is a true color image, otherwise false
is returned.
更新日志
版本 | 说明 |
---|---|
8.0.0 |
image expects a GdImage
instance now; previously, a resource was expected.
|
范例
示例 #1 Converts any image object to true color
<?php
// Backwards compatiblity
if(!function_exists('imagepalettetotruecolor'))
{
function imagepalettetotruecolor(&$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);
?>
以上例程会输出:
typeof($im) = palette typeof($im) = true color
参见
- imagecreatetruecolor() - 新建一个真彩色图像
- imageistruecolor() - 检查图像是否为真彩色图像