[PHP GD库]⑨--等比例缩略图

 $ratio_orig) {
    $dst_w = $dst_h * $ratio_orig;
} else {
    $dst_h = $dst_w / $ratio_orig;
}

$src_image = imagecreatefromjpeg($filename);
$dst_image = imagecreatetruecolor($dst_w, $dst_h);
imagecopyresampled($dst_image, $src_image, 0, 0, 0, 0, $dst_w, $dst_h, $src_w, $src_h);
imagepng($dst_image, 'images/test_thumb.jpg');
imagedestroy($src_image);
imagedestroy($dst_image);

?>

优化

适应不同格式的图片

 $ratio_orig) {
    $dst_w = $dst_h * $ratio_orig;
} else {
    $dst_h = $dst_w / $ratio_orig;
}

$src_image = $createFun($filename);
$dst_image = imagecreatetruecolor($dst_w, $dst_h);
imagecopyresampled($dst_image, $src_image, 0, 0, 0, 0, $dst_w, $dst_h, $src_w, $src_h);
$outFun($dst_image, 'images/test1_thumb.jpg');
imagedestroy($src_image);
imagedestroy($dst_image);

?>