PHP100 2019-03-27
代码如下:
function my_image_resize($src_file, $dst_file, $dst_width=32, $dst_height=32) { if($dst_width <1 || $dst_height <1) { echo "params width or height error !"; exit(); } if(!file_exists($src_file)) { echo $src_file . " is not exists !"; exit(); } $type=exif_imagetype($src_file); $support_type=array(IMAGETYPE_JPEG , IMAGETYPE_PNG , IMAGETYPE_GIF); if(!in_array($type, $support_type,true)) { echo "this type of image does not support! only support jpg , gif or png"; exit(); } switch($type) { case IMAGETYPE_JPEG : $src_img=imagecreatefromjpeg($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(); } $src_w=imagesx($src_img); $src_h=imagesy($src_img); $ratio_w=1.0 * $dst_width/$src_w; $ratio_h=1.0 * $dst_height/$src_h; if ($src_w<=$dst_width && $src_h<=$dst_height) { $x = ($dst_width-$src_w)/2; $y = ($dst_height-$src_h)/2; $new_img=imagecreatetruecolor($dst_width,$dst_height); imagecopy($new_img,$src_img,$x,$y,0,0,$dst_width,$dst_height); switch($type) { case IMAGETYPE_JPEG : imagejpeg($new_img,$dst_file,100); break; case IMAGETYPE_PNG : imagepng($new_img,$dst_file); break; case IMAGETYPE_GIF : imagegif($new_img,$dst_file); break; default: break; } } else { $dstwh = $dst_width/$dst_height; $srcwh = $src_w/$src_h; if ($ratio_w <= $ratio_h) { $zoom_w = $dst_width; $zoom_h = $zoom_w*($src_h/$src_w); } else { $zoom_h = $dst_height; $zoom_w = $zoom_h*($src_w/$src_h); } $zoom_img=imagecreatetruecolor($zoom_w, $zoom_h); imagecopyresampled($zoom_img,$src_img,0,0,0,0,$zoom_w,$zoom_h,$src_w,$src_h); $new_img=imagecreatetruecolor($dst_width,$dst_height); $x = ($dst_width-$zoom_w)/2; $y = ($dst_height-$zoom_h)/2+1; imagecopy($new_img,$zoom_img,$x,$y,0,0,$dst_width,$dst_height); switch($type) { case IMAGETYPE_JPEG : imagejpeg($new_img,$dst_file,100); break; case IMAGETYPE_PNG : imagepng($new_img,$dst_file); break; case IMAGETYPE_GIF : imagegif($new_img,$dst_file); break; default: break; } } }