PHP利用GD库处理图片方法实现
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这里写的是完成每个功能的函数，可以复制单个函数直接使用，这里的每个函数都是另外一篇PHP常用类------图片处理类Image当中的方法进行细化，可以参考一下
废话不多说，直接付代码吧！
添加水印(文字和图片）
<?php /** * [创建图片文字水印] * @param [string] $imagename [需要添加水印的值] * @param [string] $string [图片上添加的文字] * @param [string] $locate [水印位置，center,left_buttom,right_buttom三选一] * @return [null] [description] */ function create_words_watermark($imagename,$string,$locate){ list($width,$height,$type)=getimagesize($imagename); $types=array(1 => "GIF",2 => "JPEG",3 => "PNG", 4 => "SWF",5 => "PSD",6 => "BMP", 7 => "TIFF",8 => "TIFF",9 => "JPC", 10 => "JP2",11 => "JPX",12 => "JB2", 13 => "SWC",14 => "IFF",15 => "WBMP",16 => "XBM"); $type=strtolower($types[$type]); $create="imagecreatefrom".$type; $img=$create($imagename); $string_color=imagecolorallocate($img,200, 200, 200); $fontsize=4; // 图片的宽和高也可用下面两个函数获得 // $width=imagesx($img); // $height=imagesy($img); switch($locate){ case \'center\': $x=($width-imagefontwidth($fontsize)*strlen($string))/2; $y=($height-imagefontheight($fontsize))/2; break; case \'left_buttom\': $x=5; $y=($height-imagefontheight($fontsize)-3); break; case \'right_buttom\': $x=($width-imagefontwidth($fontsize)*strlen($string)-3); $y=($height-imagefontheight($fontsize)-3); break; default: die("未指定水印位置!"); break; } imagestring($img,$fontsize,$x,$y,$string,$string_color); imagestring($img,$fontsize,$x+1,$y+1,$string,$string_color); $save="image".$type; //保存 //$save($img,"new_".$imagename); //显示 header("content-type:image/".$type); $save($img); imagedestroy($img); } // create_words_watermark("test.png","hello world","right_buttom"); /** * [create_pic_watermark 添加图片水印] * @param [string] $dest_image [需要添加图片水印的图片名] * @param [string] $watermark [水印图片名] * @param [string] $locate [水印位置，center,left_buttom,right_buttom三选一] * @return [type] [description] */ function create_pic_watermark($dest_image,$watermark,$locate){ list($dwidth,$dheight,$dtype)=getimagesize($dest_image); list($wwidth,$wheight,$wtype)=getimagesize($watermark); $types=array(1 => "GIF",2 => "JPEG",3 => "PNG", 4 => "SWF",5 => "PSD",6 => "BMP", 7 => "TIFF",8 => "TIFF",9 => "JPC", 10 => "JP2",11 => "JPX",12 => "JB2", 13 => "SWC",14 => "IFF",15 => "WBMP",16 => "XBM"); $dtype=strtolower($types[$dtype]);//原图类型 $wtype=strtolower($types[$wtype]);//水印图片类型 $created="imagecreatefrom".$dtype; $createw="imagecreatefrom".$wtype; $imgd=$created($dest_image); $imgw=$createw($watermark); switch($locate){ case \'center\': $x=($dwidth-$wwidth)/2; $y=($dheight-$wheight)/2; break; case \'left_buttom\': $x=1; $y=($dheight-$wheight-2); break; case \'right_buttom\': $x=($dwidth-$wwidth-1); $y=($dheight-$wheight-2); break; default: die("未指定水印位置!"); break; } imagecopy($imgd,$imgw,$x,$y,0,0, $wwidth,$wheight); $save="image".$dtype; //显示 header("content-type:image/".$dtype); $save($imgd); imagedestroy($imgw); imagedestroy($imgd); } create_pic_watermark("ganlixin.jpg","test.png","left_buttom"); ?>
剪切图片
<?php
/**
* [cut_image] 从原图中剪切一部分
* @param [string] $old_imagename [需要剪切的图片名]
* @param [int] $start_width [从原图片宽为的$start_width开始剪切]
* @param [int] $start_height [从原图片高为的$start_height开始剪切]
* @param [int] $new_width [从原图片中剪切$new_width的宽度]
* @param [int] $new_height [从原图片中剪切$new_height的高度]
* @return [null] [null]
*/
function cut_image($old_imagename,$start_width,$start_height,$new_width,$new_height){
list($old_width,$old_height,$type)=getimagesize($old_imagename);
$types=array(1 => "GIF",2 => "JPEG",3 => "PNG",
4 => "SWF",5 => "PSD",6 => "BMP",
7 => "TIFF",8 => "TIFF",9 => "JPC",
10 => "JP2",11 => "JPX",12 => "JB2",
13 => "SWC",14 => "IFF",15 => "WBMP",16 => "XBM");
$type=strtolower($types[$type]);
$create="imagecreatefrom".$type;
$old_img=$create($old_imagename);
$new_img=imagecreatetruecolor($new_width, $new_height);
imagecopyresampled($new_img,$old_img,0,0,$start_width,$start_height,$new_width,$new_height,$new_width,$new_height);
$save="image".$type;
//保存
//$save($new_img,"new_".$old_imagename);
//显示
header("content-type:image/".$type);
$save($new_img);
//销毁
imagedestroy($old_img);
imagedestroy($new_img);
}
cut_image("ganlixin.jpg",0,0,200,200);
?>
翻转图片
<?php
/**
* [rotate_image 图片旋转]
* @param [string] $imagename [要进行旋转的图片名]
* @param [string] $angle [旋转的角度，逆时针为正]
* @return [null] [description]
*/
function rotate_image($imagename,$angle){
list($width,$height,$type)=getimagesize($imagename);
$types=array(1 => "GIF",2 => "JPEG",3 => "PNG",
4 => "SWF",5 => "PSD",6 => "BMP",
7 => "TIFF",8 => "TIFF",9 => "JPC",
10 => "JP2",11 => "JPX",12 => "JB2",
13 => "SWC",14 => "IFF",15 => "WBMP",16 => "XBM");
$type=$types[$type];
$create="imagecreatefrom".$type;
$img=$create($imagename);
$new_img=imagerotate($img,$angle,0);
$save="image".$type;
//显示
header("content-type:image/".$type);
$save($new_img);
// 保存
// $save($new_img,"new_".$imagename);
imagedestroy($img);
imagedestroy($new_img);
}
rotate_image("ganlixin.jpg",-90);
?>
翻转图片
<?php
/**
* [overturn_image 翻转图片]
* @param [string] $imagename [要反转的图片名]
* @param [char] $method [按x轴或y轴翻转，只有x，y选项]
* @return [type] [description]
*/
function overturn_image($imagename,$method){
$method=strtolower($method);
list($width,$height,$type)=getimagesize($imagename);
$types=array(1 => "GIF",2 => "JPEG",3 => "PNG",
4 => "SWF",5 => "PSD",6 => "BMP",
7 => "TIFF",8 => "TIFF",9 => "JPC",
10 => "JP2",11 => "JPX",12 => "JB2",
13 => "SWC",14 => "IFF",15 => "WBMP",16 => "XBM");
$type=$types[$type];
$create="imagecreatefrom".$type;
$img=$create($imagename);//源图片
$new_img=imagecreatetruecolor($width,$height);//翻转之后的图片
if($method==\'y\'){
for($i=0;$i<$width;$i++){
imagecopy($new_img,$img,$width-$i-1,0,$i,0,1,$height);
}
} else if($method==\'x\'){
for($i=0;$i<$height;$i++){
imagecopy($new_img,$img,0,$height-$i-1,0,$i,$width,1);
}
}
$save="image".$type;
//显示
header("content-type:image/".$type);
$save($new_img);
// 保存
// $save($new_img,"new_".$imagename);
imagedestroy($img);
imagedestroy($new_img);
}
overturn_image("ganlixin.jpg","y");
?>
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