


Complete collection of PHP image processing functions (recommended collection)_PHP tutorial
1. Create image resources
imagecreatetruecolor(width,height);
imagecreatefromgif(image name);
imagecreatefrompng(image name);
imagecreatefromjpeg(image name) ;Draw various images imagegif (image resource, save path);
imagepng()
imagejpeg();
2. Get image attributes
imagesx(res//width
imagesy(res//height
getimagesize(file path)
Returns a four-unit Array. Index 0 contains the pixel value of the image width, index 2 contains the pixel value of the image type: 1 = GIF, 2 = JPG, 3 = PNG, 4 = SWF, 5 = PSD, 6 = BMP, 7 = TIFF (intel byte order), 8 = TIFF (motorola byte order), 9 = JPC, 10 = JP2, 11 = JPX, 12 = JB2, 13 = SWC, 14 = IFF, 15 = WBMP, 16 = XBM. These tags correspond to the new IMAGETYPE constant in PHP 4.3.0. Index 3 is a text string with the content "height="yyy" width="xxx"" and can be used directly to destroy the image. Resource
imagedestroy(picture resource);
3. Transparency processing
PNG and jpeg transparent colors are normal, only gif is abnormalimagecolortransparent(resource image [,int color])//Set a certain color to be transparent Color
imagecolorstotal()
imagecolorforindex();
4. Image cropping
imagecopyresized()imagecopyresampled();
5. Add watermark (text, picture)
String encoding conversion string iconv ( string $in_charset , string $out_charset , string $str )
6. Image rotation
imagerotate();//Flip the image at a specified angle
7. Flip of the picture
Flip along the X-axis along the Y-axis
8. Sharpening
imagecolorsforindex()imagecolorat()
Draw graphics on the picture $img=imagecreatefromgif("./images/map.gif");
* Image sharpening
*/
$ red= imagecolorallocate($img, 255, 0, 0);
imageline($img, 0, 0, 100, 100, $red);
imageellipse($img, 200, 100, 100 , 100, $red);
imagegif($img, "./images/map2.gif");
imagedestroy($img);
Normal image scaling
The code is as follows:
$filename="./images/hee.jpg";
$per=0.3;
list($width, $height)=getimagesize($filename);
$n_w=$width *$per;
$n_h=$width*$per;
$new=imagecreatetruecolor($n_w, $n_h);
$img=imagecreatefromjpeg($filename);
//Copy part Image and adjust
imagecopyresized($new, $img,0, 0,0, 0,$n_w, $n_h, $width, $height);
//Image output new image, save as
imagejpeg($new, "./images/hee2.jpg");
imagedestroy($new);
imagedestroy($img);
The image is scaled proportionally and the transparent color is not processed
The code is as follows:
function thumn($background, $width, $height, $newfile) {
list($s_w, $s_h)=getimagesize($background);//Get the original image height and width
if ($width && ($s_w $width = ($height / $s_h) * $s_w;
} else {
$height = ($width / $s_w) * $s_h;
}
$new=imagecreatetruecolor($width, $height);
$img=imagecreatefromjpeg($background);
imagecopyresampled($new, $img, 0, 0, 0, 0, $width, $height, $s_w, $s_h);
imagejpeg($new, $newfile);
imagedestroy($new);
imagedestroy($img) ;
}
thumn("images/hee.jpg", 200, 200, "./images/hee3.jpg");
GIF transparent color processing
The code is as follows:
function thumn($background, $width, $height, $newfile) {
list($s_w, $s_h)=getimagesize($background);
if ($width && ($s_w $width = ($height / $s_h) * $s_w;
} else {
$height = ($width / $s_w) * $s_h;
}
$new=imagecreatetruecolor($width, $height);
$img=imagecreatefromgif($background);
$otsc=imagecolortransparent($img);
if($otsc >=0 && $ otst $tran=imagecolorsforindex($img, $otsc);//Index color value
$newt=imagecolorallocate($new, $tran[" red"], $tran["green"], $tran["blue"]);
imagefill($new, 0, 0, $newt);
imagecolortransparent($new, $newt);
}
imagecopyresized($new, $img, 0, 0, 0, 0, $width, $height, $s_w, $s_h);
imagegif($new, $newfile);
imagedestroy($new);
imagedestroy($img);
}
thumn("images/map.gif", 200, 200, "./images/map3.gif");
/**
* Image cropping
* edit by www.jbxue.com
*/
function cut($background, $cut_x, $cut_y, $cut_width, $cut_height, $location){
$back=imagecreatefromjpeg($background);
$new=imagecreatetruecolor($cut_width, $cut_height);
imagecopyresampled($new, $back, 0, 0, $cut_x, $cut_y, $cut_width, $cut_height,$cut_width,$cut_height);
imagejpeg($new, $location);
imagedestroy($new);
imagedestroy($back);
}
cut("./images/hee.jpg", 440, 140, 117, 112, "./images/hee5.jpg");
?>
图片加水印 文字水印
/**
*
* Add text watermark to pictures
*/
function mark_text($background, $text, $x, $y){
$back=imagecreatefromjpeg($background);
$color=imagecolorallocate($back, 0, 255, 0);
imagettftext($back, 20, 0, $x, $y, $color, "simkai.ttf", $text);
imagejpeg($back, "./images/hee7.jpg");
imagedestroy($back);
}
mark_text("./images/hee.jpg", "细说PHP", 150, 250);
//图片水印
function mark_pic($background, $waterpic, $x, $y){
$back=imagecreatefromjpeg($background);
$water=imagecreatefromgif($waterpic);
$w_w=imagesx($water);
$w_h=imagesy($water);
imagecopy($back, $water, $x, $y, 0, 0, $w_w, $w_h);
imagejpeg($back,"./images/hee8.jpg");
imagedestroy($back);
imagedestroy($water);
}
mark_pic("./images/hee.jpg", "./images/gaolf.gif", 50, 200);
图片旋转
/**
* Image rotation
*/
$back=imagecreatefromjpeg("./images/hee.jpg");
$new=imagerotate($back, 45, 0);
imagejpeg($new, "./images/hee9.jpg");
?>
图片水平翻转垂直翻转
/**
* Flip the image horizontally and vertically
*/
function turn_y($background, $newfile){
$back=imagecreatefromjpeg($background);
$width=imagesx($back);
$height=imagesy($back);
$new=imagecreatetruecolor($width, $height);
for($x=0; $x imagecopy($new, $back, $width-$x-1, 0, $x, 0, 1, $height);
}
imagejpeg($new, $newfile);
imagedestroy($back);
imagedestroy($new);
}
function turn_x($background, $newfile){
$back=imagecreatefromjpeg($background);
$width=imagesx($back);
$height=imagesy($back);
$new=imagecreatetruecolor($width, $height);
for($y=0; $y imagecopy($new, $back,0, $height-$y-1, 0, $y, $width, 1);
}
imagejpeg($new, $newfile);
imagedestroy($back);
imagedestroy($new);
}
turn_y("./images/hee.jpg", "./images/hee11.jpg");
turn_x("./images/hee.jpg", "./images/hee12.jpg");
?>

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