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HomeBackend DevelopmentPHP Tutorialphp gd2 上传图片/文字水印/图片水印/等比例缩略图/实现代码_php技巧

复制代码 代码如下:

//上传文件类型列表
$uptypes=array(
'image/jpg',
'image/jpeg',
'image/png',
'image/pjpeg',
'image/gif',
'image/bmp',
'image/x-png'
);
$max_file_size = 200000; //上传文件大小限制, 单位BYTE
$path_im = "prod_img/"; //生成大图保存文件夹路径
$path_sim = "prod_simg/"; //缩略图保存文件夹路径
$watermark = 1; //是否加水印(1为加水印,其他为不加水印);
$watertype = 1; //水印类型(1为文字,2为图片)
$waterstring = "[url=http://www.jy17.com/]http://www.jy17.com/[/url]"; //水印字符串
$waterimg = "water.png"; //水印图片文件路径
$waterclearly = 100; //水印透明度0-100,数字小透明高
$imclearly = 100; //图片清晰度0-100,数字越大越清晰,文件尺寸越大
$simclearly = 75; //缩略图清晰度0-100,数字越大越清晰,文件尺寸越大
$smallmark = 1; //是否生成缩略图(1为加生成,其他为不);
$dst_sw = 80; //定义缩略图宽度,高度我采用等比例缩放,所以只要比较宽度就可以了
?>

上传文件:



允许上传的文件类型为:=implode(',',$uptypes)?>

if ($_SERVER['REQUEST_METHOD'] == 'POST')
{
if (!is_uploaded_file($_FILES["upfile"][tmp_name]))
//是否存在文件
{
echo "图片不存在!";
exit;
}
$file = $_FILES["upfile"];
if($max_file_size //检查文件大小
{ $max_file_size = $max_file_size/1000;
echo "文件太大,超过 ".$max_file_size." KB!";
exit;
}
if(!in_array($file["type"],$uptypes))
//检查文件类型
{
echo "文件类型不符!".$file["type"];
exit;
}
if(!file_exists($path_im))
//检查上传目录是否存在,不存在创建
{
mkdir($path_im);
}
if(!file_exists($path_sim))
//检查缩略图目录是否存在,不存在创建
{
mkdir($path_sim);
}
$filename = $file["tmp_name"];
$im_size = getimagesize($filename);
$src_w = $im_size[0];
$src_h = $im_size[1];
$src_type = $im_size[2];
$pinfo = pathinfo($file["name"]);
$filetype = $pinfo['extension'];
$all_path = $path_im.time().".".$filetype; //路径+文件名,目前以上传时间命名
if (file_exists($all_path))
{
echo "同名文件已经存在了";
exit;
}
if(!move_uploaded_file ($filename,$all_path))
{
echo "移动文件出错";
exit;
}
$pinfo = pathinfo($all_path);
$fname = $pinfo[basename];
echo "已经成功上传
文件名: ".$all_path."
";
echo "宽度:".$src_w."px ";
echo "长度:".$src_h."px ";
echo "
大小:".$file["size"]." bytes";
switch($src_type)//判断源图片文件类型
{
case 1://gif
$src_im = imagecreatefromgif($all_path);//从源图片文件取得图像
break;
case 2://jpg
$src_im = imagecreatefromjpeg($all_path);
break;
case 3://png
$src_im = imagecreatefrompng($all_path);
break;
//case 6:
//$src_im=imagecreatefromwbmp($all_path);
//break;
default:
die("不支持的文件类型");
exit;
}
if($watermark == 1)
{
//$iinfo = getimagesize($all_path,$iinfo);
$dst_im = imagecreatetruecolor($src_w,$src_h);
//根据原图尺寸创建一个相同大小的真彩色位图
$white = imagecolorallocate($dst_im,255,255,255);//白
//给新图填充背景色
$black = imagecolorallocate($dst_im,0,0,0);//黑
$red = imagecolorallocate($dst_im,255,0,0);//红
$orange = imagecolorallocate($dst_im,255,85,0);//橙
imagefill($dst_im,0,0,$white);
imagecopymerge($dst_im,$src_im,0,0,0,0,$src_w,$src_h,100);//原图图像写入新建真彩位图中
//imagefilledrectangle($dst_im,1,$src_h-15,80,$src_h,$white);
switch($watertype)
{
case 1: //加水印字符串
imagestring($dst_im,5,5,$src_h-20,$waterstring,$orange);//文字水印,字体5号颜色橙色,位于背景图左下角
break;
case 2: //加水印图片
$lim_size = getimagesize($waterimg); //取得水印图像尺寸,信息
switch($lim_size[2]) //判断水印图片文件类型
{
case 1://gif
$src_lim = imagecreatefromgif($waterimg); //取得水印图像
break;
case 2://jpg
$src_lim = imagecreatefromjpeg($waterimg);
break;
case 3://png
$src_lim = imagecreatefrompng($waterimg);
break;
//case 6:
//$src_im=imagecreatefromwbmp($waterimg);
//break;
default:
die("不支持的文件类型");
exit;
}
$src_lw = ($src_w-$lim_size[0])/2; //水印位于背景图正中央width定位
$src_lh = ($src_h-$lim_size[1])/2; //height定位
imagecopymerge($dst_im,$src_lim,$src_lw,$src_lh,0,0,$lim_size[0],$lim_size[1],$waterclearly);// 合并两个图像,设置水印透明度$waterclearly
imagedestroy($src_lim);
break;
}
switch($src_type)
{
case 1:
imagegif($dst_im,$all_path,$imclearly);//生成gif文件,图片清晰度0-100
break;
case 2:
imagejpeg($dst_im,$all_path,$imclearly);//生成jpg文件,图片清晰度0-100
break;
case 3:
imagepng($dst_im,$all_path,$imclearly);//生成png文件,图片清晰度0-100
break;
//case 6:
//imagewbmp($dst_im,$all_path);
break;
}
//释放缓存
imagedestroy($dst_im);
}
if($smallmark == 1)
{
$sall_path = $path_sim.time().".".$filetype;
if (file_exists($sall_path))
{
echo "同名文件已经存在了";
exit;
}
if($src_w {
$dst_sim = imagecreatetruecolor($src_w,$src_h); //新建缩略图真彩位图
imagecopymerge($dst_sim,$src_im,0,0,0,0,$src_w,$src_h,100); //原图图像写入新建真彩位图中
}
if($src_w > $dst_sw) // 原图尺寸 > 缩略图尺寸
{
$dst_sh = $dst_sw/$src_w*$src_h;
$dst_sim = imagecreatetruecolor($dst_sw,$dst_sh); //新建缩略图真彩位图(等比例缩小原图尺寸)
imagecopyresampled($dst_sim,$src_im,0,0,0,0,$dst_sw,$dst_sh,$src_w,$src_h); //原图图像写入新建真彩位图中
}
switch($src_type)
{
case 1:
imagegif($dst_sim,$sall_path,$simclearly);//生成gif文件,图片清晰度0-100
break;
case 2:
imagejpeg($dst_sim,$sall_path,$simclearly);//生成jpg文件,图片清晰度0-100
break;
case 3:
imagepng($dst_sim,$sall_path,$simclearly);//生成png文件,图片清晰度0-100
break;
//case 6:
//imagewbmp($dst_sim,$sall_path);
break;
}
//释放缓存
imagedestroy($dst_sim);
}
//释放缓存
imagedestroy($src_im);
}
?>

php等比例生成缩略图函数2
复制代码 代码如下:

function reSizeImg($imgSrc, $resize_width, $resize_height, $isCut=false) {
//图片的类型
$type = substr ( strrchr ( $imgSrc, "." ), 1 );
//初始化图象
if ($type == "jpg") {
$im = imagecreatefromjpeg ( $imgSrc );
}
if ($type == "gif") {
$im = imagecreatefromgif ( $imgSrc );
}
if ($type == "png") {
$im = imagecreatefrompng ( $imgSrc );
}
//目标图象地址
$full_length = strlen ( $imgSrc );
$type_length = strlen ( $type );
$name_length = $full_length - $type_length;
$name = substr ( $imgSrc, 0, $name_length - 1 );
$dstimg = $name . "_s." . $type;
$width = imagesx ( $im );
$height = imagesy ( $im );
//生成图象
//改变后的图象的比例
$resize_ratio = ($resize_width) / ($resize_height);
//实际图象的比例
$ratio = ($width) / ($height);
if (($isCut) == 1) //裁图
{
if ($ratio >= $resize_ratio) //高度优先
{
$newimg = imagecreatetruecolor ( $resize_width, $resize_height );
imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, $resize_width, $resize_height, (($height) * $resize_ratio), $height );
ImageJpeg ( $newimg, $dstimg );
}
if ($ratio {
$newimg = imagecreatetruecolor ( $resize_width, $resize_height );
imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, $resize_width, $resize_height, $width, (($width) / $resize_ratio) );
ImageJpeg ( $newimg, $dstimg );
}
} else //不裁图
{
if ($ratio >= $resize_ratio) {
$newimg = imagecreatetruecolor ( $resize_width, ($resize_width) / $ratio );
imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, $resize_width, ($resize_width) / $ratio, $width, $height );
ImageJpeg ( $newimg, $dstimg );
}
if ($ratio $newimg = imagecreatetruecolor ( ($resize_height) * $ratio, $resize_height );
imagecopyresampled ( $newimg, $im, 0, 0, 0, 0, ($resize_height) * $ratio, $resize_height, $width, $height );
ImageJpeg ( $newimg, $dstimg );
}
}
ImageDestroy ( $im );
}
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