Ho trovato solo questo documento in proposito:

http://lists.m4if.org/pipermail/tech...ay/002070.html

Domanda: We have to convert a 3GP file created with a Nokia 3650 (containing video and audio) to a MP4 file (...)

Risposta: Nokia 3650 video track is in QCIF H.263 Video Codec.
You need to find something to encode H.263 to MP4 codec. (i.e. Philips Platform 4 or Hantro)
Nothing's free though~ tell me if you find anything free as well

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