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How to implement php code to process images

墨辰丷

May 16, 2018 am 11:59 AM

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This article mainly introduces how to implement php code to process images. Interested friends can refer to it. I hope it will be helpful to everyone.

1. Image scaling code

Non-proportional image scaling code

$fileNames=&#39;./images/hee.jpg&#39;;
list($s_w,$s_h)=getimagesize($fileNames);
$per=0.3;
$n_w=$s_w*$per;
$n_h=$s_h*$per;
$s_img=imagecreatefromjpeg($fileNames);
$n_img=imagecreatetruecolor($n_w,$n_h);
imagecopyresized($n_img,$s_img,0,0,0,0,$n_w,$n_h,$s_w,$s_h);
header("Content-Type:image/jpeg");
imagejpeg($n_img,&#39;./images/hee2.jpg&#39;);
imagedestroy($n_img);
imagedestroy($s_img);
function sf($backgroung,$bl,$location){
list($width,$height)=getimagesize($backgroung);
$n_w=$width*$bl;
$n_h=$height*$bl;
$s_img=imagecreatefromjpeg($backgroung);
$n_img=imagecreatetruecolor($n_w,$n_h);
imagecopyresized($n_img,$s_img,0,0,0,0,$n_w,$n_h,$width,$height);
header("Content-Type:image/jpeg");
imagejpeg($n_img,$location);
imagedestroy($s_img);
imagedestroy($n_img);
}
//sf(&#39;./images/hee.jpg&#39;,0.3,&#39;./images/hee9.jpg&#39;);

Equal proportion picture scaling (and adding transparent color processing)

function imagesf($backgroung,$n_w,$n_h,$newFiles){
list($s_w,$s_h,$imagetype)=getimagesize($backgroung);
//等比例缩放固定算法
if ($n_w && ($s_w < $s_h)) {
$n_w = ($n_h / $s_h) * $s_w;
} else {
$n_h = ($n_w / $s_w) * $s_h;
}
if($imagetype==2){
$s_img=imagecreatefromjpeg($backgroung);
}elseif($imagetype==3){
$s_img=imagecreatefrompng($backgroung);
}elseif($imagetype==1){
$s_img=imagecreatefromgif($backgroung);
}else{
echo "php 不支持这中图片类型！！";
}
$n_img=imagecreatetruecolor($n_w,$n_h);
//取得原图形的索引
$img_index=imagecolortransparent($s_img);
//判断原图形索引是否在图形调色板的数目范围内（调色板数目 0~255）；
if($img_index>=0 && $img_index<imagecolorstotal($s_img)){
//返回一个具有 red，green，blue 和 alpha 的键名的关联数组，包含了指定颜色索引的相应的值
$trans=imagecolorsforindex($s_img,$img_index);
//print_r($trans); Array ( [red] => 255 [green] => 255 [blue] => 255 [alpha] => 127 )
//取原图的颜色，给新图分配颜色
$n_color=imagecolorallocate($n_img,$trans[&#39;red&#39;],$trans[&#39;green&#39;],$trans[&#39;blue&#39;]);
imagefill($n_img,0,0,$n_color);
//把获取到的颜色，设置为新图的透明色
imagecolortransparent($n_img,$n_color);
}
//imagecopyresampled($n_img,$s_img,0,0,0,0,$n_w,$n_h,$s_w,$s_h);
if(imagetypes()& IMG_JPG){
header("Content-Type:image/jpeg");
imagejpeg($n_img,$newFiles);
}elseif(imagetypes()& IMG_PNG){
header("Content-Type:image/png");
imagepng($n_img,$newFiles);
}elseif(imagetypes()& IMG_GIF){
header("Content-Type:image/gif");
imagegif($n_img,$newFiles);
}else{
echo "php 不支持这中图片类型！！";
}
imagedestroy($s_img);
imagedestroy($n_img);
}
imagesf(&#39;./images/map.gif&#39;,200,200,&#39;./images/map2.gif&#39;);

2. Image cropping code

Picture cropping

function imagecut($backgroung,$cut_x,$cut_y,$cut_width,$cut_hight,$fileNames){
list(,,$imagetype)=getimagesize($backgroung);
if($imagetype==1){
$s_img=imagecreatefromgif($backgroung);
}elseif($imagetype==2){
$s_img=imagecreatefromjpeg($backgroung);
}elseif($imagetype==2){
$s_img=imagecreatefrompng($backgroung);
}else{
echo "php 不支持这种图片类型！！";
}
$n_img=imagecreatetruecolor($cut_width,$cut_hight);
imagecopyresized($n_img,$s_img,0,0,$cut_x,$cut_y,$cut_width,$cut_hight,$cut_width,$cut_hight);
if(imagetypes() & IMG_GIF){
header("Content-Type:image/gif");
imagegif($n_img,$fileNames);
}elseif(imagetypes() & IMG_JPG){
header("Content-Type:image/jpeg");
imagejpeg($n_img,$fileNames);
}elseif(imagetypes() & IMG_PNG){
header("Content-Type:image/png");
imagepng($n_img,$fileNames);
}else{
echo "php 不支持这种图片类型！！";
}
}
//imagecut(&#39;./images/hee.jpg&#39;,52, 47, 345, 330,&#39;./images/hee4.jpg&#39;);
function cut($backgroung,$x,$y,$cut_width,$cut_hight,$location){
$s_img=imagecreatefromjpeg($backgroung);
$n_img=imagecreatetruecolor($cut_width,$cut_hight);
imagecopy($n_img,$s_img,0,0,$x,$y,$cut_width,$cut_hight);
header("Content-Type:image/jpeg");
imagejpeg($n_img,$location);
imagedestroy($s_img);
imagedestroy($n_img);
}
//cut(&#39;./images/hee.jpg&#39;,52, 47, 345, 330,&#39;./images/hee8.jpg&#39;);

##Crop the image and scale the cropped image, instead of scaling the image proportionally (that is, copy part of the image and resize it) imagecopyresized() — Copy part of the image and resize it

imagecopyresampled() — Resample and resize part of the image copy

function cutsf($backgroung,$x,$y,$cut_width,$cut_hight,$n_w,$n_h,$location){
$s_img=imagecreatefromjpeg($backgroung);
$n_img=imagecreatetruecolor($n_w,$n_h);
imagecopyresized($n_img,$s_img,0,0,$x,$y,$n_w,$n_h,$cut_width,$cut_hight);
header("Content-Type:image/jpeg");
imagejpeg($n_img,$location);
imagedestroy($s_img);
imagedestroy($n_img);
}
cutsf(&#39;./images/hee.jpg&#39;,52, 47, 345, 330,200,200,&#39;./images/hee10.jpg&#39;);

##三,
Add watermark to picture: text watermark and image watermark code

Add text watermark to picture

Add image watermark to picture

function mark_pic($backgroung,$x,$y,$waterpic,$fileNames){
$s_img=imagecreatefromjpeg($backgroung);
$waterpic_img=imagecreatefromgif($waterpic);
$waterpic_w=imagesx($waterpic_img);
$waterpic_h=imagesy($waterpic_img);
imagecopy( $s_img,  $waterpic_img, $x,$y, 0,0, $waterpic_w,$waterpic_h);
header("Content-Type:image/jpeg");
imagejpeg($s_img,$fileNames);
imagedestroy($s_img);
imagedestroy($waterpic_img);
}
//mark_pic(&#39;./images/hee.jpg&#39;,50,200,&#39;./images/gaolf.gif&#39;,&#39;./images/hee6.jpg&#39;);

4. Image rotation code

##Image rotation resource imagerotate() — Rotate the image with a given angle , return the new resource

function imagexz($backgroung,$angle,$location){ $s_img=imagecreatefromjpeg($backgroung); $n_img=imagerotate($s_img,$angle,0); header("Content-Type:image/jpeg"); imagejpeg($n_img,$location); imagedestroy($s_img); imagedestroy($n_img); } imagexz('./images/hee.jpg',360,'images/hee10.jpg'); //90 180 270 360

##5. Image flipping

Flipping the image along the Y-axis means swapping left and right

function turn_y($backgroung,$newFiles){
$s_img=imagecreatefromjpeg($backgroung);
$width=imagesx($s_img);
$height=imagesy($s_img);
$n_img=imagecreatetruecolor($width,$height);
for( $x=0; $x<$width; $x++ ){
imagecopy($n_img,$s_img, $width-$x-1,0, $x,0, 1,$height);
}
header("Content-Type:image/jpeg");
imagejpeg($n_img,$newFiles);
imagedestroy($s_img);
imagedestroy($n_img);
}
//turn_y(&#39;./images/hee.jpg&#39;,&#39;./images/hee11.jpg&#39;);

## Flip the picture along the x-axis, that is, flip it up and down

function turn_x($backgroung,$newFiles){
$s_img=imagecreatefromjpeg($backgroung);
$width=imagesx($s_img);
$height=imagesy($s_img);
$n_img=imagecreatetruecolor($width,$height);
for( $y=0; $y<$height; $y++ ){
imagecopy($n_img,$s_img, 0,$height-$y-1, 0,$y, $width,1);
}
header("Content-Type:image/jpeg");
imagejpeg($n_img,$newFiles);
imagedestroy($s_img);
imagedestroy($n_img);
}
//turn_x(&#39;./images/hee.jpg&#39;,&#39;./images/hee12.jpg&#39;);

6. Image sharpening

function sharp($background, $degree, $save){
$back=imagecreatefromjpeg($background);
$b_x=imagesx($back);
$b_y=imagesy($back);
$dst=imagecreatefromjpeg($background);
for($i=$b_x-1; $i>0; $i--){
for($j=$b_y-1; $j>0; $j--){
$b_clr1=imagecolorsforindex($back, imagecolorat($back, $i-1, $j-1));
$b_clr2=imagecolorsforindex($back, imagecolorat($back, $i, $j));
$r=intval($b_clr2["red"]+$degree*($b_clr2["red"]-$b_clr1["red"]));
$g=intval($b_clr2["green"]+$degree*($b_clr2["green"]-$b_clr1["green"]));
$b=intval($b_clr2["blue"]+$degree*($b_clr2["blue"]-$b_clr1["blue"]));
$r=min(255, max($r, 0));
$g=min(255, max($g, 0));
$b=min(255, max($b, 0));
if(($d_clr=imagecolorexact($dst, $r, $g, $b))==-1){
$d_clr=Imagecolorallocate($dst, $r, $g, $b);
}
imagesetpixel($dst, $i, $j, $d_clr);
}
}
imagejpeg($dst, $save);
imagedestroy($back);
imagedestroy($dst);
}
sharp("./images/hee.jpg", 20, "./images/hee15.jpg");

#Image sharpening (analytical principle) (first obtain the color of the original image, then sharpen the color of the original image, and finally assign the sharpened color to the original image)

#解析开始：
#1 创建要锐化的图片资源
#eg:$s_img=imagecreatefromjpeg('./images/hee.jpg');
#2 获取图片资源的宽、高，创建两层循环（外层控制宽内层控制高）对每一个像素进行锐化
#eg:$width=imagesx($s_img);
# $height=imagesy($s_img);
# for($i=$width-1; $i>0; $i--){
# for($j=$height-1; $j>0; $j--){
#
# }
# }
#3 在内层循环里对每一个像素颜色进行锐化（写在内层循环）：
#3.1 用函数$color=imagecolorsforindex()取得图片索引的颜色，即取得当前颜色和取得上一个颜色
#eg: $s_img_color1=imagecolorsforindex($s_img , imagecolorat($s_img , $i-1, $j-1));//上一个颜色
# $s_img_color2=imagecolorsforindex($s_img , imagecolorat($s_img , $i, $j));//当前颜色
#3.2 固定算法对取得的颜色进行锐化比如锐化20：$degree=20
#eg:$r=intval($color["red"]+$degree*($color["red"]-$color["red"]));
# $g=intval($s_img_color2["green"]+$degree*($s_img_color2["green"]-$s_img_color1["green"]));
# $b=intval($s_img_color2["blue"]+$degree*($s_img_color2["blue"]-$s_img_color1["blue"]));
#3.3 把取得的RGB颜色控制在0~255正常范围内
#$r=min(255, max($r, 0));
#$g=min(255, max($g, 0));
#$b=min(255, max($b, 0));
#4 把锐化后的每一个像素颜色重新赋给原图的每一个像素颜色（写在内层循环）
#4.1 取得锐化后颜色的索引：$rh_color
#eg:if( ($rh_color=imagecolorexact($s_img,$r,$g,$b)) ==-1){
# $rh_color=imagecolorallocate($s_img,$r,$g,$b);
# }
#4.2 把锐化后的每一个像素颜色重新赋给原图的每一个像素颜色
eg:imagesetpixel($s_img, $i, $j, $rh_color);
#5 保存图片资源（写在循环外）
#eg:imagejpeg($s_img'./images/hee16.jpg');
#6 关闭图片资源（写在循环外）
#eg:imagedestroy($s_img);
#解析结束

根据解决在写一遍图片锐化代码
function sharp($background, $degree, $location){
#step 1 创建图片资源
$s_img=imagecreatefromjpeg($background);
#step 2 获取图片资源的宽高
$b_x=imagesx($s_img);
$b_y=imagesy($s_img);
#step 3 两层循环进行锐化  外层控制宽 内层控制高
for( $i=$b_x-1; $i>0; $i-- ){
for( $j=$b_y-1; $j>0; $j-- ){
#step 4 取得图片索引的颜色：当前颜色和上一个颜色
$s_img_color1=imagecolorsforindex($s_img, imagecolorat($s_img, $i-1, $j-1));
$s_img_color2=imagecolorsforindex($s_img, imagecolorat($s_img, $i, $j));
#step 5 固定算法对取得的颜色进行锐化
$r=intval($s_img_color2["red"]+$degree*($s_img_color2["red"]-$s_img_color1["red"]));
$g=intval($s_img_color2["green"]+$degree*($s_img_color2["green"]-$s_img_color1["green"]));
$b=intval($s_img_color2["blue"]+$degree*($s_img_color2["blue"]-$s_img_color1["blue"]));
#step 6 把取得的RGB颜色控制在0~255正常范围内
$r=min(255, max($r, 0));
$g=min(255, max($g, 0));
$b=min(255, max($b, 0));
#step 7 取得锐化后颜色的索引
if( ($d_clr=imagecolorexact($s_img,$r,$g,$b)) ==-1){
$d_clr=imagecolorallocate($s_img,$r,$g,$b);
}
#step 8 把锐化后的颜色重新赋给图片资源的每一个像素
imagesetpixel($s_img, $i, $j, $d_clr);
}
}
imagejpeg($s_img,$location);
imagedestroy($s_img);
}
sharp(&#39;./images/hee.jpg&#39;,50,&#39;./images/hee16.jpg&#39;);
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