I'm on Xubuntu. Two days ago, I wanted to download a mp3 song from YouTube: this one using this firefox extension or any other. The size is 82 MB. It's clearly not an mp3 file; it's a video that has an
.mp3 extension. All the video data are still there.
So I wonder, do all downloaders work the same? For example, could I download this video using this extension, in the lowest possible quality to save bandwidth, and then convert it to HD using ffmpeg or whatever?
I don't think that downloaders are capable of converting videos; they just change the extension of the file to reduce its size a bit. Am I wrong?