我有一个页面，仅用于打印，其中的一些图像是通过我拥有的脚本上传的。它似乎总是将图像降低到 72 dpi，不管我设置什么imagejpeg()和imagepng()质量。
我在 git hub 上使用过我自己的个人脚本和这个
https://github.com/maxim/smart_resize_image
我希望获得一些关于将 dpi 保留为原始 300dpi 的指导。
这是我自己的个人脚本
if (!empty($_FILES['image']['name'])) //checking if file upload box contains a value
{
$saveDirectory = 'pics/'; //name of folder to upload to
$tempName = $_FILES['image']['tmp_name']; //getting the temp name on server
$fileName1 = $_FILES['image']['name']; //getting file name on users computer
$count = 1;
do{
$location = $saveDirectory . $_GET['section'] . $count . $fileName1;
$count++;
}while(is_file($location));
if (move_uploaded_file($tempName, $location)) //Moves the temp file on server
{ //to directory with real name
$image = $location;
// Get new sizes
list($width, $height, $type) = getimagesize($image); //gets information about new server image
$framewidth = 932;
$frameheight = 354;
$realwidth = $width; //setting original width and height
$realheight = $height;
// Load
$file1new = imagecreatetruecolor($framewidth, $frameheight); //creates all black image with target w/h
if($type == 2){
$source = imagecreatefromjpeg($image);
imagecopyresampled($file1new, $source , 0, 0, 0, 0, $framewidth, $frameheight, $realwidth, $realheight);
}
elseif($type == 3){
$source = imagecreatefrompng($image);
imagecopyresampled($file1new, $source , 0, 0, 0, 0, $framewidth, $frameheight, $realwidth, $realheight);
}
else{
echo "Wrong file type";
}
if($type == 2){
//creates jpeg image from file1new for file1 (also retains quality)
imagejpeg($file1new, $image,100);
//frees space
imagedestroy($file1new);
}
elseif($type == 3){
//creates png image from file1new for file1 (also retains quality)
imagepng($file1new, $image,10);
//frees space
imagedestroy($file1new);
}
else{
echo "Wrong file type";
}
}
else
{
echo '<h1> There was an error while uploading the file.</h1>';
}
}
}
编辑：即使 dpi 不是答案，因为我看到 jpgs 具体不会保留该信息。我需要一些方法来保持这些图像非常清晰和清晰。