PHP文件/图像转换器

I am currently learning PHP a little bit and I want to see a example for a file converter.

I mean png to jpg or something. It would be really helpfull I tried so much things like this :

imagepng(imagecreatefromstring(file_get_contents(input)), 'out.png');

You can get the data from a file, in this case an image by using file_get_contents:

$data = file_get_contents("img.png");

Once you have the data to form the new file, you can then use the function file_put_contents to write your new file:

if (file_put_contents("img.jpg", $data)) {
    echo("success");
} else {
    echo("failure");
}

file_put_contents returns an int of 0 or 1 so you can determine if it was successful in creating the file.

You could then create the following function:

function imagepng($input, $output) {
    return file_put_contents($output, $input);
}

Hope this is helpful.