假如做过那种门户站的朋侪,一定晓得,一张图片能够会在差别的处所显现、大小差别、比例也差别,假如只用一张图的话,那末一定会变形,而且在显现小图的处所,链接大图,又太浪费了.....用缩略图来处置惩罚,也不圆满,由于每一个处所涌现的比例大小能够都不一样 。 (引荐进修:PHP视频教程)
PHP自动裁切比拟你们看到过相似那种图片地点/aaaa/abc_200_100.jpg 或许/aaaa/abc_200*100.jpg
我的体式格局就是在须要图片处所把这个图片地点转化为相似上面的那种地点, 然后经由过程apache 的rewrite 定向到一个处置惩罚顺序。依据宽高生成一个图片然后保存起来,在不动原图的任何信息和位置的情况下对图片做处置惩罚。
不好的处所,就是生成的图片能够会比较多,占用的空间也比较大,然则假如是本身服务器 那就无所谓了,能够归类整顿下
OK 送上代码,我们就以discuz为例
function crop_img($img, $width = 200, $height = 200) { $img_info = parse_url($img); /* 外部链接直接返回图片地点 */ if (!empty($img_info['host']) && $img_info['host'] != $_SERVER['HTTP_HOST']) { return $img; } else { $pos = strrpos($img, '.'); $img = substr($img, 0, $pos) . '_' . $width . '_' . $height . substr($img, $pos); return $img; } } function img($img,$width,$height){ $img_info = parse_url($img); /* 外部链接直接返回图片地点 */ if (!empty($img_info['host']) && $img_info['host'] != $_SERVER['HTTP_HOST']) { return $img; } else { $pos = strrpos($img, '.'); $img = substr($img, 0, $pos) . '_' . $width . '_' . $height . substr($img, $pos); echo '<img src="'.$img.'" width="'.$width.'" height="'.$height.'" />'; return ; } }
函数的用法 crop_img('原图地点','宽度','高度'); 这个函数返回处置惩罚过的图片地点,img 函数直接返回图片标签字符串,比如在discuz模板内里挪用这个函数 {eval img($pic,200,100)}
如许返回的地点就是/data/attachment/forum/aaaaaa_200_100.jpg 现在来讲 这个图片是不存在 那末看第二步
第二步 须要增加apache的rewrite划定规矩
<IfModule mod_rewrite.c> RewriteEngine on RewriteCond %{REQUEST_FILENAME} !-d RewriteCond %{REQUEST_FILENAME} !-f RewriteRule ^data/attachment/(.*)$ images.php?url=$1 [L] </IfModule>
上面的意义,就是 data/attachement/这个地点开首不存在的文件都定向到image.php来处置惩罚,而且把url当参数传过去
第三步 就是image.php 这个内里的代码里
<?php $url = $_GET['url']; $src = './data/attachment/' . preg_replace('/_(\d+)_(\d+)/', '', $url); $filename = './data/attachment/' . $url; if (file_exists($filename)) { ob_start(); header('Content-type:image/jpeg'); readfile($filename); ob_flush(); flush(); } else { if(!preg_match('/_(\d+)_(\d+)/', $url, $wh)){ defulat(); exit(); } $width = $wh[1]; $height = $wh[2]; thumb(realpath($src), $width, $height, $filename, 'crop', '85'); } function thumb($src, $width, $height, $filename, $mode = 'scale', $quality = '100') { try { $imageValue = getimagesize($src); $sourceWidth = $imageValue[0]; //原图宽 $sourceHeight = $imageValue[1]; //原图高 $thumbWidth = $width; //缩略图宽 $thumbHeight = $height; //缩略图高 $_x = 0; $_y = 0; $w = $sourceWidth; $h = $sourceHeight; if ($mode == 'scale') { if ($sourceWidth <= $thumbWidth && $sourceHeight <= $thumbHeight) { $_x = floor(($thumbWidth - $sourceWidth) / 2); $_y = floor(($thumbHeight - $sourceHeight) / 2); $thumbWidth = $sourceWidth; $thumbHeight = $sourceHeight; } else { if ($thumbHeight * $sourceWidth > $thumbWidth * $sourceHeight) { $thumbHeight = floor($sourceHeight * $width / $sourceWidth); $_y = floor(($height - $thumbHeight) / 2); } else { $thumbWidth = floor($sourceWidth * $height / $sourceHeight); $_x = floor(($width - $thumbWidth) / 2); } } } else if ($mode == 'crop') { if ($sourceHeight < $thumbHeight) { //假如原图尺寸小于当前尺寸 $thumbWidth = floor($thumbWidth * $sourceHeight / $thumbHeight); $thumbHeight = $sourceHeight; } if ($sourceWidth < $thumbWidth) { $thumbHeight = floor($thumbHeight * $sourceWidth / $thumbWidth); $thumbWidth = $sourceWidth; } $s1 = $sourceWidth / $sourceHeight; //原图比例 $s2 = $width / $height; //新图比例 if ($s1 == $s2) { } else if ($s1 > $s2) { //全高度 $y = 0; $ax = floor($sourceWidth * ($thumbHeight / $sourceHeight)); $x = ($ax - $thumbWidth) / 2; $w = $thumbWidth / ($thumbHeight / $sourceHeight); } else { //全宽度 $x = 0; $ay = floor($sourceHeight * ($thumbWidth / $sourceWidth)); //模仿原图比例高度 $y = ($ay - $thumbHeight) / 2; $h = $thumbHeight / ($thumbWidth / $sourceWidth); } } switch ($imageValue[2]) { case 2: $source = imagecreatefromjpeg($src); break; case 1: $source = imagecreatefromgif($src); break; case 3: $source = imagecreatefrompng($src); break; case 6: $source = imagecreatefromwbmp($src); break; default: defulat(); return; } header("Content-type: image/jpeg"); $thumb = imagecreatetruecolor($width, $height); imagefill($thumb, 0, 0, imagecolorallocate($thumb, 255, 255, 255)); imagecopyresampled($thumb, $source, 0, 0, $x, $y, $width, $height, $w, $h); imagejpeg($thumb, null, $quality); // if ($_SERVER['HTTP_REFERER'] || false !== stripos($_SERVER['HTTP_REFERER'], 'http://' . $_SERVER['SERVER_NAME'])) { imagejpeg($thumb, $filename, $quality); // } imagedestroy($thumb); imagedestroy($source); } catch (Exception $ex) { defulat(); } } function defulat() { $default_img = realpath('media/images/nopic.jpg'); ob_start(); header('Content-type:image/jpeg'); readfile($default_img); ob_flush(); flush(); }
thumb 函数 能够掌握 裁切体式格局,scale 为等比缩放,不裁切,不够的处所 用白色添补,crop 为裁切,假如请求的宽高比 大于原图宽高比,那末就坚持最大显现宽度,居中裁切高低过剩部份,假如请求宽高比小于原图宽高比,那末就坚持最大高度,居中裁切摆布过剩部份,总而言之,在坚持不变形的前提下 ,把图片减少,而且最大保存图片的内容.哈哈 这个代码有多叼,尝尝晓得了,,,固然你须要支撑rewrite功用和GD2 支撑
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