PHP image cropping thumbnail cropping class source code and usage method, thumbnail cropping_PHP tutorial

PHP image cropping thumbnail cropping class source code and usage method, thumbnail cropping

Recently I am working on an open source project of dragging and dropping verification codes on web pages, and I need to generate images on the server side The corresponding movable color blocks, but the resources on the Internet are all for thumbnails and scaling of the entire image, so I made my own and completed the tool for cropping small pieces of the image

<&#63;php
namespace App\Libs;
/**
* 2016-01-07 15:54:58
* Lixiaoyu
* 
* 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
*/
class ImageCrop{
var $sImage;
var $dImage;
var $src_file;
var $dst_file;
var $src_width;
var $src_height;
var $src_ext;
var $src_type;
function __construct($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 &#63; $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 &#63; $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 &#63; $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 &#63; $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 &#63; $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 &#63; $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 &#63; $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
/**
*
* 裁切方法
* 2016-01-07 15:05:44
* Lixiaoyu
*
* @param $dst_width 目标长
* @param $dst_height 目标高
* @param $dst_x 裁剪部分和PHP image cropping thumbnail cropping class source code and usage method, thumbnail cropping_PHP tutorial左侧的距离
* @param $dst_y 裁剪部分和PHP image cropping thumbnail cropping class source code and usage method, thumbnail cropping_PHP tutorial右侧的距离
* @param int $mode 模式
* @param string $dst_file 目标文件路径
*/
function Cut($dst_width,$dst_height,$dst_x,$dst_y,$dst_file='')
{
if ($dst_file) $this->dst_file = $dst_file; //设置目标文件位置
$this->dImage = imagecreatetruecolor($dst_width, $dst_height); //创建了目标文件的大小的画布
$bg = imagecolorallocatealpha($this->dImage, 255, 255, 255, 127); //给画布分配颜色
imagefill($this->dImage, 0, 0, $bg); //给图像用颜色进行填充
imagecolortransparent($this->dImage, $bg); //背景定义成透明色
$ratio_w = 1.0 * $dst_width / $this->src_width; //横向缩放的比例
$ratio_h = 1.0 * $dst_height / $this->src_height; //纵向缩放的比例
//var_dump($this);
//不进行缩放,直接对图像进行裁剪
$ratio = 1.0;
$tmp_w = (int)($dst_width / $ratio);
$tmp_h = (int)($dst_height / $ratio);
$tmp_img = imagecreatetruecolor($dst_width, $dst_height); //创建暂时保存的画布
imagecopy($tmp_img, $this->sImage, 0,0,$dst_x,$dst_y,$dst_width,$dst_height); //拷贝出图像的一部分,进行裁切
imagecopyresampled($this->dImage,$tmp_img,0,0,0,0,$dst_width,$dst_height,$tmp_w,$tmp_h); //把暂时缓存的图片,放到目标文件里面
imagedestroy($tmp_img);
}
}
&#63;>

Use

Crop image

$ic=new ImageCrop($pathToFile,'./pic/afterCrop'.time().'.jpg');
$ic->Cut(40,30,120,130);
$ic->SaveImage();
//$ic->SaveAlpha();将补白变成透明像素保存
$ic->destory();

Achieve results

Original image

Picture after cropping

Zoom image

Original image

Thumbnail

The focus of this article is on using the image processing functions imagecopy and imagecopyresampled

bool imagecopy ( resource dstim,resourcesrc_im , int dstx,intdst_y , int srcx,intsrc_y , int srcw,intsrc_h )
Copy the part of the src_im image whose coordinates start from src_x, src_y, have a width of src_w, and a height of src_h to the position of the dst_im image where the coordinates are dst_x and dst_y.

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http://www.bkjia.com/PHPjc/1089571.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/1089571.htmlTechArticlePHP image cropping thumbnail cropping class source code and usage method, thumbnail cropping is currently doing web drag and drop verification The open source project of code needs to generate movable color blocks corresponding to the picture on the server side, but...