我正在尝试将JPG（以及任何图像）转换为PNG。我有一个HTML表单，可以很好地将图像发布到服务器上。我需要重命名该文件，并将其转换为PNG。稍后在我执行相关表数据库插入后的代码中，我再次重命名该文件，以将记录ID附加到文件名以确保其唯一性。
我更像是一个客观的C程序员，然后是PHP，所以我在这里遇到了这个代码，我在其他问题中发现这些代码似乎对我不起作用。
以下是print_r($_FILES);
Array ( [image] => Array ( [name] => BBnL9Ho.jpg [type] => image/jpeg [tmp_name] => /tmp/phphhqHam [error] => 0 [size] => 1636 ) )
所以，我想将其转换为PNG并重命名BBnL9Ho.jpg to image1.png。我尝试使用以下代码，但无济于事：
$newfileName = imagepng(imagecreatefromjpeg($_FILES['image']['tmp_name']), "image1.png");
稍后我执行相关的数据库表INSERT之后，我再次更改名称并附加相关数据库记录的ID（我将文件名存储在单独的表中，然后由于一对多关系将其余的表单数据存储）：
$fileName="$lastinsertID".$newfileName;
然后我将该名称插入正确输入的数据库中。然后我需要将文件移动到上传目录，我尝试这样做：
move_uploaded_file("$fileName",$dir . $fileName);
这是我的问题所在。文件没有移动。当我检查文件的属性时，似乎它实际上并没有转换文件。我用它来检查类型：
$fileType = $_FILES["image"]["type"];
它仍然显示它是JPG。我必须遗漏一些非常明显的东西，但我会感激一些帮助。
非常感谢。
答案 0 :(得分：1)
使用以下脚本将任何图像（JPEG，PNG和GIF）转换为PNG格式。仔细阅读以下脚本，我在每个关键步骤都添加了评论。
// $dir specifies the directory where you upload your image files
// get the file by it's temporary name
$tmp_file_name = $_FILES['image']['tmp_name'];
// get the file extension
$ext = strtolower(pathinfo($_FILES['image']['name'], PATHINFO_EXTENSION));
// specify the whole path here
$actual_file_name = $dir . basename($_FILES['image']['name'], "." . $ext) . ".png";
// check whether a valid image is uploaded or not
if(getimagesize($tmp_file_name)){
// get the mime type of the uploaded image
$image_array = getimagesize($tmp_file_name);
$mime_type = $image_array['mime'];
// get the height and width of the uploaded image
list($width_orig, $height_orig) = getimagesize($tmp_file_name);
$width = $width_orig;
$height = $height_orig;
if($mime_type == "image/gif"){
// create a new true color image
if($image_p = imagecreatetruecolor($width, $height)){
// create a new image from file
if($image = imagecreatefromgif($tmp_file_name)){
// copy and resize part of an image with resampling
if(imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig)){
if(imagepng($image_p, $actual_file_name, 0)){
// image is successfully uploaded
// free resources
imagedestroy($image_p);
imagedestroy($image);
// perform the insert operation and get the last inserted id
// $lastinsertID = XXXX
// new file name
$filename = $dir . $lastinsertID . basename($_FILES['image']['name'], "." . $ext) . ".png";
//move the file to your desired location
if(rename($actual_file_name, $filename)){
echo "success";
}else{
echo "error";
}
}else{
//Destroy both image resource handler
imagedestroy($image);
imagedestroy($image_p);
echo "Error";
}
}else{
//Destroy both image resource handlers
imagedestroy($image);
imagedestroy($image_p);
echo "Error";
}
}else{
//destroy $image_p image resource handler
imagedestroy($image_p);
echo "Error";
}
}else{
echo "Error";
}
}elseif($mime_type == "image/png"){
// the uploaded image is already in .png format
if(move_uploaded_file($tmp_file_name, $actual_file_name)){
// perform the insert operation and get the last inserted id
// $lastinsertID = XXXX
// new file name
$filename = $dir . $lastinsertID . $_FILES['image']['name'];
//move the file to your desired location
if(rename($actual_file_name, $filename)){
echo "success";
}else{
echo "error";
}
}else{
echo "error";
}
}elseif($mime_type == "image/jpeg"){
// create a new true color image
if($image_p = imagecreatetruecolor($width, $height)){
// create a new image from file
if($image = imagecreatefromjpeg($tmp_file_name)){
// copy and resize part of an image with resampling
if(imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig)){
if(imagepng($image_p, $actual_file_name, 0)){
// image is successfully uploaded
// free resources
imagedestroy($image_p);
imagedestroy($image);
// perform the insert operation and get the last inserted id
// $lastinsertID = XXXX
// new file name
$filename = $dir . $lastinsertID . basename($_FILES['image']['name'], "." . $ext) . ".png";
//move the file to your desired location
if(rename($actual_file_name, $filename)){
echo "success";
}else{
echo "error";
}
}else{
//Destroy both image resource handler
imagedestroy($image);
imagedestroy($image_p);
echo "Error";
}
}else{
//Destroy both image resource handlers
imagedestroy($image);
imagedestroy($image_p);
echo "Error";
}
}else{
//destroy $image_p image resource handler
imagedestroy($image_p);
echo "Error";
}
}else{
echo "error_An unexpected error has been occured. Please try again later.";
}
}else{
echo "Only JPEG, PNG and GIF images are allowed.";
}
}else{
echo "Bad image format";
}