Extract audio in PHP

[ghost]

Hello, when i use --extract-audio --audio-format mp3, the extensionof downloaded file is .webm always.
In terminal work's fine.Extract MP3, but in PHP not working.

Code: <?php echo exec("youtube-dl --extract-audio --audio-format mp3 https://www.youtube.com/watch?v=VIDEO_ID "); ?>

THANK YOU.

[dstftw]

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