这里有新鲜出炉的 PHP 面向对象编程,程序狗速度看过来!
PHP(外文名: Hypertext Preprocessor,中文名:"超文本预处理器")是一种通用开源脚本语言。语法吸收了 C 语言、Java 和 Perl 的特点,入门门槛较低,易于学习,使用广泛,主要适用于 web 开发领域。PHP 的文件后缀名为 php。
这篇文章主要介绍了 PHP 全功能无变形图片裁剪操作类与用法, 结合实例形式分析了 php 操作图片的裁剪、缩放等相关技巧, 需要的朋友可以参考下
本文实例讲述了 PHP 全功能无变形图片裁剪操作类与用法。分享给大家供大家参考,具体如下:
如果需要图片裁剪,或生成缩略图,这个基本上没有问题,全部需要的功能都在里面,全部都是无变形的。
这里我们划分为四种模式:
1. 任意图片裁剪到指定大小,超过的,剧中裁剪,并且最大化缩放,不够的拉伸,
2. 超过的剧中裁剪,而不足的,不拉伸,即只缩小,不放大裁剪,会产生补白,可以用 png 透明度来消除
3. 保留全部图片信息。不裁剪,只缩放,不足的补白。
4. 保留全部图片信息。不裁剪,只缩放,不足的不补白,产生的图片为实际有效像素大小,例如有个图片是 600X600 现在要生成 120X100 那么缩放后的实际有效像素为 100X100,所以只生成 100X100 的图片,而第三种模式则生成 120X100 的大小,并且有补白
- <?php
- /**
- * Author : smallchicken
- * mode 1 : 强制裁剪,生成图片严格按照需要,不足放大,超过裁剪,图片始终铺满
- * mode 2 : 和1类似,但不足的时候 不放大 会产生补白,可以用png消除。
- * mode 3 : 只缩放,不裁剪,保留全部图片信息,会产生补白,
- * mode 4 : 只缩放,不裁剪,保留全部图片信息,生成图片大小为最终缩放后的图片有效信息的实际大小,不产生补白
- * 默认补白为白色,如果要使补白成透明像素,请使用SaveAlpha()方法代替SaveImage()方法
- *
- * 调用方法:
- *
- * $ic=new ImageCrop('old.jpg','afterCrop.jpg');
- * $ic->Crop(120,80,2);
- * $ic->SaveImage();
- * //$ic->SaveAlpha();将补白变成透明像素保存
- * $ic->destory();
- *
- *
- */
- class ImageCrop {
- var $sImage;
- var $dImage;
- var $src_file;
- var $dst_file;
- var $src_width;
- var $src_height;
- var $src_ext;
- var $src_type;
- function ImageCrop($src_file,$dst_file='') {
- $this->src_file=$src_file;
- $this->dst_file=$dst_file;
- $this->LoadImage();
- }
- function SetSrcFile($src_file) {
- $this->src_file=$src_file;
- }
- function SetDstFile($dst_file) {
- $this->dst_file=$dst_file;
- }
- function LoadImage() {
- list($this->src_width, $this->src_height, $this->src_type) = getimagesize($this->src_file);
- switch($this->src_type) {
- case IMAGETYPE_JPEG :
- $this->sImage=imagecreatefromjpeg($this->src_file);
- $this->ext='jpg';
- break;
- case IMAGETYPE_PNG :
- $this->sImage=imagecreatefrompng($this->src_file);
- $this->ext='png';
- break;
- case IMAGETYPE_GIF :
- $this->sImage=imagecreatefromgif($this->src_file);
- $this->ext='gif';
- break;
- default:
- exit();
- }
- }
- function SaveImage($fileName='') {
- $this->dst_file=$fileName ? $fileName : $this->dst_file;
- switch($this->src_type) {
- case IMAGETYPE_JPEG :
- imagejpeg($this->dImage,$this->dst_file,100);
- break;
- case IMAGETYPE_PNG :
- imagepng($this->dImage,$this->dst_file);
- break;
- case IMAGETYPE_GIF :
- imagegif($this->dImage,$this->dst_file);
- break;
- default:
- break;
- }
- }
- function OutImage() {
- switch($this->src_type) {
- case IMAGETYPE_JPEG :
- header('Content-type: image/jpeg');
- imagejpeg($this->dImage);
- break;
- case IMAGETYPE_PNG :
- header('Content-type: image/png');
- imagepng($this->dImage);
- break;
- case IMAGETYPE_GIF :
- header('Content-type: image/gif');
- imagegif($this->dImage);
- break;
- default:
- break;
- }
- }
- function SaveAlpha($fileName='') {
- $this->dst_file=$fileName ? $fileName . '.png' : $this->dst_file .'.png';
- imagesavealpha($this->dImage, true);
- imagepng($this->dImage,$this->dst_file);
- }
- function OutAlpha() {
- imagesavealpha($this->dImage, true);
- header('Content-type: image/png');
- imagepng($this->dImage);
- }
- function destory() {
- imagedestroy($this->sImage);
- imagedestroy($this->dImage);
- }
- function Crop($dst_width,$dst_height,$mode=1,$dst_file='') {
- if($dst_file) $this->dst_file=$dst_file;
- $this->dImage = imagecreatetruecolor($dst_width,$dst_height);
- $bg = imagecolorallocatealpha($this->dImage,255,255,255,127);
- imagefill($this->dImage, 0, 0, $bg);
- imagecolortransparent($this->dImage,$bg);
- $ratio_w=1.0 * $dst_width / $this->src_width;
- $ratio_h=1.0 * $dst_height / $this->src_height;
- $ratio=1.0;
- switch($mode) {
- case 1: // always crop
- if( ($ratio_w < 1 && $ratio_h < 1) || ($ratio_w > 1 && $ratio_h > 1)) {
- $ratio = $ratio_w < $ratio_h ? $ratio_h : $ratio_w;
- $tmp_w = (int)($dst_width / $ratio);
- $tmp_h = (int)($dst_height / $ratio);
- $tmp_img=imagecreatetruecolor($tmp_w , $tmp_h);
- $src_x = (int) (($this->src_width-$tmp_w)/2) ;
- $src_y = (int) (($this->src_height-$tmp_h)/2) ;
- imagecopy($tmp_img, $this->sImage, 0,0,$src_x,$src_y,$tmp_w,$tmp_h);
- imagecopyresampled($this->dImage,$tmp_img,0,0,0,0,$dst_width,$dst_height,$tmp_w,$tmp_h);
- imagedestroy($tmp_img);
- } else {
- $ratio = $ratio_w < $ratio_h ? $ratio_h : $ratio_w;
- $tmp_w = (int)($this->src_width * $ratio);
- $tmp_h = (int)($this->src_height * $ratio);
- $tmp_img=imagecreatetruecolor($tmp_w ,$tmp_h);
- imagecopyresampled($tmp_img,$this->sImage,0,0,0,0,$tmp_w,$tmp_h,$this->src_width,$this->src_height);
- $src_x = (int)($tmp_w - $dst_width) / 2 ;
- $src_y = (int)($tmp_h - $dst_height) / 2 ;
- imagecopy($this->dImage, $tmp_img, 0,0,$src_x,$src_y,$dst_width,$dst_height);
- imagedestroy($tmp_img);
- }
- break;
- case 2: // only small
- if($ratio_w < 1 && $ratio_h < 1) {
- $ratio = $ratio_w < $ratio_h ? $ratio_h : $ratio_w;
- $tmp_w = (int)($dst_width / $ratio);
- $tmp_h = (int)($dst_height / $ratio);
- $tmp_img=imagecreatetruecolor($tmp_w , $tmp_h);
- $src_x = (int) ($this->src_width-$tmp_w)/2 ;
- $src_y = (int) ($this->src_height-$tmp_h)/2 ;
- imagecopy($tmp_img, $this->sImage, 0,0,$src_x,$src_y,$tmp_w,$tmp_h);
- imagecopyresampled($this->dImage,$tmp_img,0,0,0,0,$dst_width,$dst_height,$tmp_w,$tmp_h);
- imagedestroy($tmp_img);
- } elseif($ratio_w > 1 && $ratio_h > 1) {
- $dst_x = (int) abs($dst_width - $this->src_width) / 2 ;
- $dst_y = (int) abs($dst_height -$this->src_height) / 2;
- imagecopy($this->dImage, $this->sImage,$dst_x,$dst_y,0,0,$this->src_width,$this->src_height);
- } else {
- $src_x=0;
- $dst_x=0;
- $src_y=0;
- $dst_y=0;
- if(($dst_width - $this->src_width) < 0) {
- $src_x = (int) ($this->src_width - $dst_width)/2;
- $dst_x =0;
- } else {
- $src_x =0;
- $dst_x = (int) ($dst_width - $this->src_width)/2;
- }
- if( ($dst_height -$this->src_height) < 0) {
- $src_y = (int) ($this->src_height - $dst_height)/2;
- $dst_y = 0;
- } else {
- $src_y = 0;
- $dst_y = (int) ($dst_height - $this->src_height)/2;
- }
- imagecopy($this->dImage, $this->sImage,$dst_x,$dst_y,$src_x,$src_y,$this->src_width,$this->src_height);
- }
- break;
- case 3: // keep all image size and create need size
- if($ratio_w > 1 && $ratio_h > 1) {
- $dst_x = (int)(abs($dst_width - $this->src_width )/2) ;
- $dst_y = (int)(abs($dst_height- $this->src_height)/2) ;
- imagecopy($this->dImage, $this->sImage, $dst_x,$dst_y,0,0,$this->src_width,$this->src_height);
- } else {
- $ratio = $ratio_w > $ratio_h ? $ratio_h : $ratio_w;
- $tmp_w = (int)($this->src_width * $ratio);
- $tmp_h = (int)($this->src_height * $ratio);
- $tmp_img=imagecreatetruecolor($tmp_w ,$tmp_h);
- imagecopyresampled($tmp_img,$this->sImage,0,0,0,0,$tmp_w,$tmp_h,$this->src_width,$this->src_height);
- $dst_x = (int)(abs($tmp_w -$dst_width )/2) ;
- $dst_y = (int)(abs($tmp_h -$dst_height)/2) ;
- imagecopy($this->dImage, $tmp_img, $dst_x,$dst_y,0,0,$tmp_w,$tmp_h);
- imagedestroy($tmp_img);
- }
- break;
- case 4: // keep all image but create actually size
- if($ratio_w > 1 && $ratio_h > 1) {
- $this->dImage = imagecreatetruecolor($this->src_width,$this->src_height);
- imagecopy($this->dImage, $this->sImage,0,0,0,0,$this->src_width,$this->src_height);
- } else {
- $ratio = $ratio_w > $ratio_h ? $ratio_h : $ratio_w;
- $tmp_w = (int)($this->src_width * $ratio);
- $tmp_h = (int)($this->src_height * $ratio);
- $this->dImage = imagecreatetruecolor($tmp_w ,$tmp_h);
- imagecopyresampled($this->dImage,$this->sImage,0,0,0,0,$tmp_w,$tmp_h,$this->src_width,$this->src_height);
- }
- break;
- }
- }
- // end Crop
- }
- ?>
希望本文所述对大家 PHP 程序设计有所帮助。
来源: http://www.phperz.com/article/17/0807/340719.html