How to check whether a MIME type is of JPG, PNG, BMP or GIF?

Question

I have written this code:

$filename = "some/path/where/the/file/can/be/found.some_extension";
$buffer = file_get_contents($filename);
$finfo = new finfo(FILEINFO_MIME_TYPE);
var_dump($finfo->buffer($buffer));
finfo_close($finfo);

Possible outputs were of:

"image/jpeg", "image/png", "image/gif", "image/x-ms-bmp"

I would like to know, what are the possible outputs of $finfo->buffer($buffer), if the file is a png, gif, bmp, or jpg?

I have seen here a returnMIMEType function, which, for instance will not detect "image/x-ms-bmp" to be a bmp.

Answer 1

We can view the possible MIME types of file extensions by searching for the file extension at the link provided by Pitchinnate. For instance BMP MIME types can be found at: filext.com/file-extension/BMP

Answer 2

In this thread, you can find some useful suggestions and functions for your situation.