php图像处理函数大全(推荐收藏)

/**
* 图片锐化处理
*/
$red= imagecolorallocate($img,255,0);imageline($img,100,$red);
imageellipse($img,200,$red);
imagegif($img,"./images/map2.gif");
imagedestroy($img);
图片普通缩放
代码如下:$filename="./images/hee.jpg";
$per=0.3;
list($width,$height)=getimagesize($filename);
$n_w=$width*$per;
$n_h=$width*$per;
$new=imagecreatetruecolor($n_w,$n_h);
$img=imagecreatefromjpeg($filename);
//拷贝部分图像并调整
imagecopyresized($new,$img,$n_w,$n_h,$width,$height);
//图像输出新图片、另存为
imagejpeg($new,"./images/hee2.jpg");
imagedestroy($new);
imagedestroy($img);图片等比例缩放、没处理透明色
代码如下:
function thumn($background,$height,$newfile) {
list($s_w,$s_h)=getimagesize($background);//获取原图片高度、宽度
if ($width && ($s_w < $s_h)) {
$width = ($height / $s_h) * $s_w;
} else {
$height = ($width / $s_w) * $s_h;
}
$new=imagecreatetruecolor($width,$height);
$img=imagecreatefromjpeg($background);
imagecopyresampled($new,$s_w,$s_h);
imagejpeg($new,$newfile);
imagedestroy($new);
imagedestroy($img);
}
thumn("images/hee.jpg","./images/hee3.jpg");gif透明色处理
代码如下:
function thumn($background,$s_h)=getimagesize($background);
if ($width && ($s_w < $s_h)) {
$width = ($height / $s_h) * $s_w;
} else {
$height = ($width / $s_w) * $s_h;
}
$new=imagecreatetruecolor($width,$height);
$img=imagecreatefromgif($background);
$otsc=imagecolortransparent($img);
if($otsc >=0 && $otst < imagecolorstotal($img)){//判断索引色
$tran=imagecolorsforindex($img,$otsc);//索引颜色值
$newt=imagecolorallocate($new,$tran["red"],$tran["green"],$tran["blue"]);
imagefill($new,$newt);
imagecolortransparent($new,$newt);
}
imagecopyresized($new,$s_h);
imagegif($new,$newfile);
imagedestroy($new);
imagedestroy($img);
}
thumn("images/map.gif","./images/map3.gif");

/**
* 图片裁剪处理
* edit by www.52php.cn
*/
function cut($background,$cut_x,$cut_y,$cut_width,$cut_height,$location){
$back=imagecreatefromjpeg($background);
$new=imagecreatetruecolor($cut_width,$cut_height);
imagecopyresampled($new,$back,$cut_height);
imagejpeg($new,$location);
imagedestroy($new);
imagedestroy($back);
}
cut("./images/hee.jpg",440,140,117,112,"./images/hee5.jpg");
?>

/**
*
* 图片添加文字水印
*/function mark_text($background,$text,$x,$y){
$back=imagecreatefromjpeg($background);
$color=imagecolorallocate($back,0);
imagettftext($back,20,$y,$color,"simkai.ttf",$text);
imagejpeg($back,"./images/hee7.jpg");
imagedestroy($back);
}
mark_text("./images/hee.jpg","细说PHP",150,250);
//图片水印
function mark_pic($background,$waterpic,$y){
$back=imagecreatefromjpeg($background);
$water=imagecreatefromgif($waterpic);
$w_w=imagesx($water);
$w_h=imagesy($water);
imagecopy($back,$water,$w_w,$w_h);
imagejpeg($back,"./images/hee8.jpg");
imagedestroy($back);
imagedestroy($water);
}
mark_pic("./images/hee.jpg","./images/gaolf.gif",50,200);

/**
* 图片旋转
*/
$back=imagecreatefromjpeg("./images/hee.jpg");$new=imagerotate($back,45,0);
imagejpeg($new,"./images/hee9.jpg");
?>

/**
* 图片水平翻转 垂直翻转
*/
function turn_y($background,$newfile){
$back=imagecreatefromjpeg($background);
$width=imagesx($back);
$height=imagesy($back);
$new=imagecreatetruecolor($width,$height);
for($x=0; $x < $width; $x++){
imagecopy($new,$width-$x-1,1,$height);
}
imagejpeg($new,$newfile);
imagedestroy($back);
imagedestroy($new);
}
function turn_x($background,$height);
for($y=0; $y < $height; $y++){
imagecopy($new,$height-$y-1,1);
}
imagejpeg($new,$newfile);
imagedestroy($back);
imagedestroy($new);
}
turn_y("./images/hee.jpg","./images/hee11.jpg");
turn_x("./images/hee.jpg","./images/hee12.jpg");
?>