MarkJane
4/18/2017 - 2:29 AM
php 处理图片 生成缩略图 以及验证码 裁剪图片等处理 图片按比例调整大小
php 处理图片 生成缩略图 以及验证码 裁剪图片等处理 图片按比例调整大小
<?php
//生成图像缩略图和生成验证码
class Image {
//生成图像验证码
static public function buildImageVerify($width = 48, $height = 22, $randval = NULL, $verifyName = 'verify') {
if (!isset($_SESSION)) {
session_start();
//如果没有开启，session，则开启session
}
$randval = empty($randval) ? ("" . rand(1000, 9999)) : $randval;
$_SESSION[$verifyName] = $randval;
$length = 4;
$width = ($length * 10 + 10) > $width ? $length * 10 + 10 : $width;
$im = imagecreate($width, $height);
$r = array(225, 255, 255, 223);
$g = array(225, 236, 237, 255);
$b = array(225, 236, 166, 125);
$key = mt_rand(0, 3);
$backColor = imagecolorallocate($im, $r[$key], $g[$key], $b[$key]);
//背景色（随机）
$borderColor = imagecolorallocate($im, 100, 100, 100);
//边框色
$pointColor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
//点颜色
@imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
@imagerectangle($im, 0, 0, $width - 1, $height - 1, $borderColor);
$stringColor = imagecolorallocate($im, mt_rand(0, 200), mt_rand(0, 120), mt_rand(0, 120));
// 干扰
for ($i = 0; $i < 10; $i++) {
$fontcolor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
imagearc($im, mt_rand(-10, $width), mt_rand(-10, $height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $fontcolor);
}
for ($i = 0; $i < 25; $i++) {
$fontcolor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
imagesetpixel($im, mt_rand(0, $width), mt_rand(0, $height), $pointColor);
}
for ($i = 0; $i < $length; $i++) {
imagestring($im, 5, $i * 10 + 5, mt_rand(1, 8), $randval{$i}, $stringColor);
}
self::output($im, 'png');
}
//生成缩略图
static public function thumb($image, $thumbname, $domain = 'public', $maxWidth = 200, $maxHeight = 50, $interlace = true) {
// 获取原图信息
$info = self::getImageInfo($image);
if ($info !== false) {
$srcWidth = $info['width'];
$srcHeight = $info['height'];
$type = strtolower($info['type']);
$interlace = $interlace ? 1 : 0;
unset($info);
$scale = min($maxWidth / $srcWidth, $maxHeight / $srcHeight);
// 计算缩放比例
if ($scale >= 1) {// 超过原图大小不再缩略
$width = $srcWidth;
$height = $srcHeight;
} else {// 缩略图尺寸
$width = (int)($srcWidth * $scale);
$height = (int)($srcHeight * $scale);
}
//sae平台上图片处理
if (class_exists('SaeStorage')) {
$saeStorage = new SaeStorage();
$saeImage = new SaeImage();
$saeImage -> setData(file_get_contents($image));
$saeImage -> resize($width, $height);
$thumbname = str_replace(array('../', './'), '', $thumbname);
return $saeStorage -> write($domain, $thumbname, $saeImage -> exec());
}
// 载入原图
$createFun = 'ImageCreateFrom' . ($type == 'jpg' ? 'jpeg' : $type);
$srcImg = $createFun($image);
//创建缩略图
if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
$thumbImg = imagecreatetruecolor($width, $height);
} else {
$thumbImg = imagecreate($width, $height);
}
// 复制图片
if (function_exists("ImageCopyResampled")) {
imagecopyresampled($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height, $srcWidth, $srcHeight);
} else {
imagecopyresized($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height, $srcWidth, $srcHeight);
}
if ('gif' == $type || 'png' == $type) {
$background_color = imagecolorallocate($thumbImg, 0, 255, 0);
// 指派一个绿色
imagecolortransparent($thumbImg, $background_color);
// 设置为透明色，若注释掉该行则输出绿色的图
}
// 对jpeg图形设置隔行扫描
if ('jpg' == $type || 'jpeg' == $type) {
imageinterlace($thumbImg, $interlace);
}
$dir = dirname($thumbname);
if (!is_dir($dir)) {
@mkdir($dir, 0777, true);
}
// 生成图片
$imageFun = 'image' . ($type == 'jpg' ? 'jpeg' : $type);
$imageFun($thumbImg, $thumbname);
imagedestroy($thumbImg);
imagedestroy($srcImg);
return $thumbname;
}
return false;
}
/**
* 图片水印
* @$image 原图
* @$water 水印图片
* @$$waterPos 水印位置(0-9) 0为随机，其他代表上中下9个部分位置
*/
static public function water($image, $water, $waterPos = 9) {
//检查图片是否存在
if (!file_exists($image) || !file_exists($water))
return false;
//读取原图像文件
$imageInfo = self::getImageInfo($image);
$image_w = $imageInfo['width'];
//取得水印图片的宽
$image_h = $imageInfo['height'];
//取得水印图片的高
$imageFun = "imagecreatefrom" . $imageInfo['type'];
$image_im = $imageFun($image);
//读取水印文件
$waterInfo = self::getImageInfo($water);
$w = $water_w = $waterInfo['width'];
//取得水印图片的宽
$h = $water_h = $waterInfo['height'];
//取得水印图片的高
$waterFun = "imagecreatefrom" . $waterInfo['type'];
$water_im = $waterFun($water);
switch ($waterPos) {
case 0 :
//随机
$posX = rand(0, ($image_w - $w));
$posY = rand(0, ($image_h - $h));
break;
case 1 :
//1为顶端居左
$posX = 0;
$posY = 0;
break;
case 2 :
//2为顶端居中
$posX = ($image_w - $w) / 2;
$posY = 0;
break;
case 3 :
//3为顶端居右
$posX = $image_w - $w;
$posY = 0;
break;
case 4 :
//4为中部居左
$posX = 0;
$posY = ($image_h - $h) / 2;
break;
case 5 :
//5为中部居中
$posX = ($image_w - $w) / 2;
$posY = ($image_h - $h) / 2;
break;
case 6 :
//6为中部居右
$posX = $image_w - $w;
$posY = ($image_h - $h) / 2;
break;
case 7 :
//7为底端居左
$posX = 0;
$posY = $image_h - $h;
break;
case 8 :
//8为底端居中
$posX = ($image_w - $w) / 2;
$posY = $image_h - $h;
break;
case 9 :
//9为底端居右
$posX = $image_w - $w;
$posY = $image_h - $h;
break;
default :
//随机
$posX = rand(0, ($image_w - $w));
$posY = rand(0, ($image_h - $h));
break;
}
//设定图像的混色模式
imagealphablending($image_im, true);
imagecopy($image_im, $water_im, $posX, $posY, 0, 0, $water_w, $water_h);
//拷贝水印到目标文件
//生成水印后的图片
$bulitImg = "image" . $imageInfo['type'];
$bulitImg($image_im, $image);
//释放内存
$waterInfo = $imageInfo = null;
imagedestroy($image_im);
}
static protected function getImageInfo($img) {
$imageInfo = getimagesize($img);
if ($imageInfo !== false) {
$imageType = strtolower(substr(image_type_to_extension($imageInfo[2]), 1));
$imageSize = filesize($img);
$info = array("width" => $imageInfo[0], "height" => $imageInfo[1], "type" => $imageType, "size" => $imageSize, "mime" => $imageInfo['mime']);
return $info;
} else {
return false;
}
}
static protected function output($im, $type = 'png', $filename = '') {
header("Content-type: image/" . $type);
$ImageFun = 'image' . $type;
if (empty($filename)) {
$ImageFun($im);
} else {
$ImageFun($im, $filename);
}
imagedestroy($im);
exit ;
}
}
// 使用示例：
// $Image = new Image();
// echo $Image->buildImageVerify($width=48,$height=22,$randval=NULL,$verifyName='verify');
?><?php
/**
*图片按比例调整大小的原理：
*1、比较原图大小是否小于等于目标大小，如果是则直接采用原图宽高
*2、如果原图大小超过目标大小，则对比原图宽高大小
*3、如：宽>高，则宽=目标宽, 高=目标宽的比例 * 原高
*4、如：高>宽，则高=目标高，宽=目标高的比例 * 原宽
**/
$image = "test.jpg";
$max_width = 200;
$max_height = 200;
$size = getimagesize($image); //得到图像的大小
$width = $size[0];
$height = $size[1];
$x_ratio = $max_width / $width;
$y_ratio = $max_height / $height;
if (($width <= $max_width) && ($height <= $max_height)){
$tn_width = $width;
$tn_height = $height;
}
elseif (($x_ratio * $height) < $max_height) {
$tn_height = ceil($x_ratio * $height);
$tn_width = $max_width;
} else{
$tn_width = ceil($y_ratio * $width);
$tn_height = $max_height;
}
$src = imagecreatefromjpeg($image);
$dst = imagecreatetruecolor($tn_width, $tn_height); //新建一个真彩色图像
imagecopyresampled($dst, $src, 0, 0, 0, 0,$tn_width, $tn_height, $width, $height); //重采样拷贝部分图像并调整大小
header('Content-Type: image/jpeg');
imagejpeg($dst,null,100);
imagedestroy($src);
imagedestroy($dst);
?>