Most consumer stuff [ie things that are likely to use mp4] will add its own small delay on the loop anyway. The mp4 properties says: Dimensions: x Codec: H. This means the command:. The different kinds of fades sine, linear, inverted parabola, and so on , as well as the options fade offers fade-in, fade-out , are listed in the sox man page. You can also use average bit rate ABR encoding, e.
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