How to convert .mp4 videos to .m4r format.
Converting MPEG-4 Videos directly to iPhone Ringtone Files (.mp4 to .m4r conversion) should be possible and relates to users attempting to extract the audio track from an MP4 video and transform it into an M4R iPhone ringtone.
Use one of several video editing programs or (online) conversion tools, such as Aiseesoft iPhone Ringtone Maker or Tiny Audio Converter, which allow users to import MP4 videos and export them in M4R format.
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