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HomeBackend DevelopmentPHP TutorialPHP image cropping function (keeping the image unchanged)_PHP tutorial

In order to automatically crop the image after uploading, and then display the cropped image in the foreground.
The requirements are as above and the source code is as follows:

Copy the code The code is as follows:


*exif_imagetype -- Determine the type of an image
*Description: The function is to crop an image into an image of any size without deformation of the image
* Parameter description: Enter the file name of the image to be processed, generate the save file name of the new image, generate the width of the new image, and generate the height of the new image
*/
// Obtain an image of any size, stretch the insufficient areas without deformation , Leave a blank Function My_image_resize ($ SRC_FILE, $ DST_FILE, $ New_width, $ New_height) {
$ New_width = INTVAL ($ new_width);
$ NE w_height = intval ($ new_width);
If ($ new_width & lt; 1 || $ new_height & lt; 1) {
echo "params width or height error!";
exit ();
}
if (! File_exists ($ src_file) {
echo $ src_file. "is not exists!";
exit ();
}
// image type
$ type = exif_imageType ($ src_file); > $ SUPPORT_TYPE = Array (ImageType_jpeg, ImageType_png, ImageType_gif); s Type of Image Does Not Support! Only support jpg, gif or png";
exit();
}
//Load image
switch($type) {
case IMAGETYPE_JPEG:
$s rc_img=imagecreatefromjpeg($src_file);
break;
case IMAGETYPE_PNG :
$src_img=imagecreatefrompng($src_file);
break;
case IMAGETYPE_GIF :
$src_img=imagecreatefromgif($src_file);
break;
default:
echo "Load image error!";
exit();
}
$w=imagesx($src_img);
$h=imagesy($src_img);
$ratio_w=1.0 * $new_width / $w;
$ratio_h=1.0 * $new_height / $h;
$ratio=1.0;
// The aspect ratio of the generated image is the original They are all small or large, the principle is to increase the large proportion, and the large proportion of reduction (the reduction ratio is relatively small)
if (($ Ratio_w & LT; 1 && $ raatio_h & lt; 1) || ($ Ratio_w >1 Use the ratio standard to crop or enlarge
}else {
      $ratio = $ratio_w ;
    }
                                                                                                                                                                     new_height / $ratio);
$inter_img=imagecreatetruecolor($inter_w, $inter_h);
//var_dump($inter_img);
imagecopy($inter_img, $src_img, 0,0,0,0 ,$inter_w,$inter_h);
// Generate a temporary image with the maximum side length as the size of the target image $ratio ratio
// Define a new image
new_width, $new_height); inter_h);
switch($type) {
case IMAGETYPE_JPEG:
imagejpeg($new_img, $dst_file,100); // Store image
break;
case IMAGETYPE_PNG :
imagepng($new_img,$dst_file,100);
break;
case IMAGETYPE_GIF:
imagegif($new_img,$dst_file,100);
break;
                                                                                                                                                                           . ;
                                                                                                                                                                                                                 ( ($ratio_w 1) || ($ratio_w >1 && $ratio_h   else{
    $ratio=$ratio_h>$ratio_w? $ratio_h : $ratio_w; //Take the value with the larger ratio
// Define a large middle image whose height or width is equal to the target image, and then enlarge the original image
$inter_w=(int)($ w * $ratio);
$inter_h=(int) ($h * $ratio);
$inter_img=imagecreatetruecolor($inter_w, $inter_h);
//Crop the original image after scaling
              imagecopyresampled($inter_img,$src_img,0,0,0,0,$inter_w,$inter_h,$w,$h); 
                                                                                                                                         $new_width,$new_height);
imagecopy($new_img, $inter_img, 0,0,0,0,$new_width,$new_height);
switch($type) {
case IMAGETYPE_JPEG :
Imagejpeg($new_img, $dst_file,100); // Store image
break;
case IMAGETYPE_PNG:
imagepng($new_img,$dst_file,100);
break;
case IMAGETYPE_GIF:
imagegif($new_img,$dst_file,100);
break;
default:
break;
}
}// if3
}// end function
my_image_resize('test.gif','11111.gif','100px','100px');
?>

www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/764612.htmlTechArticleIn order to automatically crop the image after uploading, and then display the cropped image in the front desk. The requirements are as above and the source code is as follows: Copy the code The code is as follows: ? *exif_imagetype -- Determine a...
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