php縮圖代碼，imagecopyresampled函數產生縮圖

function CreateImage($SrcImageUrl, $DirImageUrl, $Width, $Height) { $img; $srcw; $new_width; $srch; $new_height; // 圖片類型 $type = substr(strrchr($SrcImageUrl, "."), 1); // 初始化映像 if($type == "jpg") $img = imagecreatefromjpeg($SrcImageUrl); if($type == "gif") $img = imagecreatefromgif($SrcImageUrl); if($type == "png") $img = imagecreatefrompng($SrcImageUrl); $srcw = imagesx($img); $srch = imagesy($img); if ($srcw / $srch > $Width / $Height) { if ($srcw > $Width) { $new_width = $Width; $new_height = $srch * ($Width / $srcw); } else { $new_width = $srcw; $new_height = $srch; } } else { if ($srch > $Height) { $new_height = $Height; $new_width = $srcw * ($Height / $srch); } else { $new_width = $srcw; $new_height = $srch; } } $new_image = imagecreatetruecolor($new_width, $new_height); imagecopyresampled($new_image, $img, 0, 0, 0, 0, $new_width, $new_height, $srcw, $srch); imagejpeg($new_image, $DirImageUrl); imagedestroy($img); imagedestroy($new_image); } 複製代碼 3、改進後代碼： /* *$o_photo 原圖路徑 *$d_photo 處理後圖片路徑 *$width 定義寬 *$height 定義高 *調用方法 cutphoto("test.jpg","temp.jpg",256,146); */ function cutphoto($o_photo,$d_photo,$width,$height){ $temp_img = imagecreatefromjpeg($o_photo); $o_width = imagesx($temp_img); //取得原圖寬 $o_height = imagesy($temp_img); //取得原圖高 //判斷處理方法 if($width>$o_width || $height>$o_height){//原圖寬或高比規定的尺寸小,進行壓縮 $newwidth=$o_width; $newheight=$o_height; if($o_width>$width){ $newwidth=$width; $newheight=$o_height*$width/$o_width; } if($newheight>$height){ $newwidth=$newwidth*$height/$newheight; $newheight=$height; } //縮圖片 $new_img = imagecreatetruecolor($newwidth, $newheight); imagecopyresampled($new_img, $temp_img, 0, 0, 0, 0, $newwidth, $newheight, $o_width, $o_height); imagejpeg($new_img , $d_photo); imagedestroy($new_img); }else{//原圖寬與高都比規定尺寸大,進行壓縮後裁剪 if($o_height*$width/$o_width>$height){//先確定width與規定相同,如果height比規定大,則ok $newwidth=$width; $newheight=$o_height*$width/$o_width; $x=0; $y=($newheight-$height)/2; }else{ //否則確定height與規定相同,width自適應 $newwidth=$o_width*$height/$o_height; $newheight=$height; $x=($newwidth-$width)/2; $y=0; } //縮圖片 $new_img = imagecreatetruecolor($newwidth, $newheight); imagecopyresampled($new_img, $temp_img, 0, 0, 0, 0, $newwidth, $newheight, $o_width, $o_height); imagejpeg($new_img , $d_photo); imagedestroy($new_img); $temp_img = imagecreatefromjpeg($d_photo); $o_width = imagesx($temp_img); //取得縮圖寬 $o_height = imagesy($temp_img); //取得縮圖高 //裁剪圖片 $new_imgx = imagecreatetruecolor($width,$height); imagecopyresampled($new_imgx,$temp_img,0,0,$x,$y,$width,$height,$width,$height); imagejpeg($new_imgx , $d_photo); imagedestroy($new_imgx); } } ?> 複製代碼

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