php图像处理函数大全(缩放、剪裁、缩放、翻转、旋转、透明、锐化的实例)

一、创建图片资源
imagecreatetruecolor(width,height);
imagecreatefromgif(图片名称);
imagecreatefrompng(图片名称);
imagecreatefromjpeg(图片名称);画出各种图像 imagegif(图片资源,保存路径);
imagepng()
imagejpeg();

二、获取图片属性
imagesx(res//宽度
imagesy(res//高度
getimagesize(文件路径)
返回一个具有四个单元的数组。索引 0 包含图像宽度的像素值，索引 1 包含图像高度的像素值。索引 2 是图像类型的标记：1 = GIF，2 = JPG，3 = PNG，4 = SWF，5 = PSD，6 = BMP，7 = TIFF(intel byte order)，8 = TIFF(motorola byte order)，9 = JPC，10 = JP2，11 = JPX，12 = JB2，13 = SWC，14 = IFF，15 = WBMP，16 = XBM。这些标记与 PHP 4.3.0 新加的 IMAGETYPE 常量对应。索引 3 是文本字符串，内容为“height="yyy" width="xxx"”，可直接用于 IMG 标记。
销毁图像资源
imagedestroy(图片资源);

三、透明处理
PNG、jpeg透明色都正常，只有gif不正常
imagecolortransparent(resource image [,int color])//将某个颜色设置成透明色
imagecolorstotal()
imagecolorforindex();

四、图片的裁剪
imagecopyresized()
imagecopyresampled();

五、加水印（文字、图片）
字符串编码转换string iconv ( string $in_charset , string $out_charset , string $str )

六、图片旋转
imagerotate();//制定角度的图片翻转

七、图片的翻转
沿X轴 沿Y轴翻转

八、锐化
imagecolorsforindex()
imagecolorat()
在图片上画图形 $img=imagecreatefromgif("./images/map.gif");

 1 <?PHP 2 /** 3 * 图片锐化处理 4 * edit by www.jbxue.com 5 */ 6 $red= imagecolorallocate($img, 255, 0, 0); 7  8 imageline($img, 0, 0, 100, 100, $red); 9 imageellipse($img, 200, 100, 100, 100, $red);10 imagegif($img, "./images/map2.gif");11 imagedestroy($img);12 图片普通缩放13 复制代码 代码如下:14 15 $filename="./images/hee.jpg";16 $per=0.3;17 list($width, $height)=getimagesize($filename);18 $n_w=$width*$per;19 $n_h=$width*$per;20 $new=imagecreatetruecolor($n_w, $n_h);21 $img=imagecreatefromjpeg($filename);22 //拷贝部分图像并调整23 imagecopyresized($new, $img,0, 0,0, 0,$n_w, $n_h, $width, $height);24 //图像输出新图片、另存为25 imagejpeg($new, "./images/hee2.jpg");26 imagedestroy($new);27 imagedestroy($img);28 29 图片等比例缩放、没处理透明色30 复制代码 代码如下:31 32 function thumn($background, $width, $height, $newfile) {33 list($s_w, $s_h)=getimagesize($background);//获取原图片高度、宽度34 if ($width && ($s_w < $s_h)) {35 $width = ($height / $s_h) * $s_w;36 } else {37 $height = ($width / $s_w) * $s_h;38 }39 $new=imagecreatetruecolor($width, $height);40 $img=imagecreatefromjpeg($background);41 imagecopyresampled($new, $img, 0, 0, 0, 0, $width, $height, $s_w, $s_h);42 imagejpeg($new, $newfile);43 imagedestroy($new);44 imagedestroy($img);45 }46 thumn("images/hee.jpg", 200, 200, "./images/hee3.jpg");47 48 gif透明色处理49 复制代码 代码如下:50 51 function thumn($background, $width, $height, $newfile) {52 list($s_w, $s_h)=getimagesize($background);53 if ($width && ($s_w < $s_h)) {54 $width = ($height / $s_h) * $s_w;55 } else {56 $height = ($width / $s_w) * $s_h;57 }58 $new=imagecreatetruecolor($width, $height);59 $img=imagecreatefromgif($background);60 $otsc=imagecolortransparent($img);61 if($otsc >=0 && $otst < imagecolorstotal($img)){//判断索引色62 $tran=imagecolorsforindex($img, $otsc);//索引颜色值63 $newt=imagecolorallocate($new, $tran["red"], $tran["green"], $tran["blue"]);64 imagefill($new, 0, 0, $newt);65 imagecolortransparent($new, $newt);66 }67 imagecopyresized($new, $img, 0, 0, 0, 0, $width, $height, $s_w, $s_h);68 imagegif($new, $newfile);69 imagedestroy($new);70 imagedestroy($img);71 }72 thumn("images/map.gif", 200, 200, "./images/map3.gif");

图片裁剪

<?php/*** 图片裁剪处理* edit by www.jbxue.com*/function cut($background, $cut_x, $cut_y, $cut_width, $cut_height, $location){$back=imagecreatefromjpeg($background);$new=imagecreatetruecolor($cut_width, $cut_height);imagecopyresampled($new, $back, 0, 0, $cut_x, $cut_y, $cut_width, $cut_height,$cut_width,$cut_height);imagejpeg($new, $location);imagedestroy($new);imagedestroy($back);}cut("./images/hee.jpg", 440, 140, 117, 112, "./images/hee5.jpg");?>

图片加水印 文字水印

 1 <?PHP 2 /** 3 *  4 * 图片添加文字水印 5 */ 6  7 function mark_text($background, $text, $x, $y){ 8 $back=imagecreatefromjpeg($background); 9 $color=imagecolorallocate($back, 0, 255, 0);10 imagettftext($back, 20, 0, $x, $y, $color, "simkai.ttf", $text);11 imagejpeg($back, "./images/hee7.jpg");12 imagedestroy($back);13 }14 mark_text("./images/hee.jpg", "细说PHP", 150, 250);15 //图片水印16 function mark_pic($background, $waterpic, $x, $y){17 $back=imagecreatefromjpeg($background);18 $water=imagecreatefromgif($waterpic);19 $w_w=imagesx($water);20 $w_h=imagesy($water);21 imagecopy($back, $water, $x, $y, 0, 0, $w_w, $w_h);22 imagejpeg($back,"./images/hee8.jpg");23 imagedestroy($back);24 imagedestroy($water);25 }26 mark_pic("./images/hee.jpg", "./images/gaolf.gif", 50, 200);

图片旋转

 1 <?PHP 2 /** 3 * 图片旋转 4 * edit by www.jbxue.com 5 */ 6 $back=imagecreatefromjpeg("./images/hee.jpg"); 7  8 $new=imagerotate($back, 45, 0); 9 imagejpeg($new, "./images/hee9.jpg");10 ?>

图片水平翻转垂直翻转

 1 <?php 2 /** 3 * 图片水平翻转 垂直翻转 4 * edit by www.jbxue.com 5 */ 6 function turn_y($background, $newfile){ 7  8 $back=imagecreatefromjpeg($background); 9 $width=imagesx($back);10 $height=imagesy($back);11 $new=imagecreatetruecolor($width, $height);12 for($x=0; $x < $width; $x++){13 imagecopy($new, $back, $width-$x-1, 0, $x, 0, 1, $height);14 }15 imagejpeg($new, $newfile);16 imagedestroy($back);17 imagedestroy($new);18 }19 function turn_x($background, $newfile){20 $back=imagecreatefromjpeg($background);21 $width=imagesx($back);22 $height=imagesy($back);23 $new=imagecreatetruecolor($width, $height);24 for($y=0; $y < $height; $y++){25 imagecopy($new, $back,0, $height-$y-1, 0, $y, $width, 1);26 }27 imagejpeg($new, $newfile);28 imagedestroy($back);29 imagedestroy($new);30 }31 turn_y("./images/hee.jpg", "./images/hee11.jpg");32 turn_x("./images/hee.jpg", "./images/hee12.jpg");33 ?>