使用PHP更改文件扩展名

Question

Is it "good" to change an image file extension?

For instance, I have a jpg file inputed, and I change it to a png. Is this OK or should I leave it as a jpg?

I use the rename() to change the name and the file extension.

It is related to PHP, because I do my renaming with PHP with a upload script.

Another question is: Is it safe to do it e.g can the files become corrupt?

Answer 1

Changing an image file extension from .jpg to .png does not change it to a PNG file. It just changes the name of the file. This does not change the contents of the file at all, so it does not become corrupt. It only changes the name of it.