(PHP 4 >= 4.0.6, PHP 5)
imagetruecolortopalette — Convert a true color image to a palette image
imagetruecolortopalette() converts a truecolor image to a palette image. The code for this function was originally drawn from the Independent JPEG Group library code, which is excellent. The code has been modified to preserve as much alpha channel information as possible in the resulting palette, in addition to preserving colors as well as possible. This does not work as well as might be hoped. It is usually best to simply produce a truecolor output image instead, which guarantees the highest output quality.
imagecreatetruecolor() 등의 이미지 생성 함수에서 반환한 이미지 자원.
Indicates if the image should be dithered - if it is TRUE then dithering will be used which will result in a more speckled image but with better color approximation.
Sets the maximum number of colors that should be retained in the palette.
성공할 경우 TRUE를, 실패할 경우 FALSE를 반환합니다.
Example #1 Converting a true color image to a palette-based image
<?php
// Create a new true color image
$im = new imagecreatetruecolor(100, 100);
// Convert to palette-based with no dithering and 255 colors
imagetruecolortopalette($im, false, 255);
// Save the image
imagepng($im, './paletteimage.png');
imagedestroy($im);
?>
Note: 이 함수는 GD 2.0.1 이상이 필요합니다. (2.0.28 이상을 권장합니다)