dion2wav

dion2wav is a simple program for transformation files created by MP3 player/voice recorder DION-MX (Oracom ORC-100) to wav-format.

Download

dion2wav-1.00.tar.gz 10Kb 2003.02.09

Installation

In order to install
  1. unarchive source code: tar -zxvf dion2wav-1.00.tar.gz
  2. make
  3. Log in as a root user and execute make install

Usage

In order to transform the input vrf file into the output wav-file, run
dion2wav input_vrf_file > output_wav_file
In order to play vrf file, execute
dion2wav input_vrf_file | sox -t wav - -r 16000 -t ossdsp -l /dev/dsp polyphase 
(requires sox installed and configured to support ossdsp driver).

Learn more about usage of DION-MX MP3 player/voice recorder under Linux.

How does it work

Although the manufacturer does not provide any information about internal voice format, it turned out not too difficult to guess. The file consists of 138 bytes long records. Each record contains a 10-bytes long header and a 128-bytes long body. The header has a 4-bytes long identifier ox7F7F0A00 and 6 bytes of some information. I failed to guess what is the meaning of the header, maybe it is for playing vrf file by the player, but it turned out not important for decoding. The body is encoded in IMA ADPCM format.

dion2wav first learns the size of the vrf file, then creates the RIFF header. It reads the records of the input vrf file, discards first 10 bytes, and decodes the body of each record using adpcm_decoder routine developed by Jack Jansen. Resulting stream is written in standard output.

License

GNU public license.


Web page was prepared by Leonid Petrov
Last update: 2003.02.01 19:48:27