MPEG-4 Audio VM

Readme file: README_frame

$Id: readme_frame,v 1.1.1.1 1998/06/09 01:05:46 lueck Exp $

Authors:
HP    Heiko Purnhagen, Uni Hannover <purnhage@tnt.uni-hannover.de>

Changes:
29-oct-96   HP    born
11-dec-96   HP    new enc options: -nh -ms -bi -ni -vr
**********************************************************************



General command line options
----------------------------

Use the command line option "-h" to get help about all the available
command line options of the VM binary.

To control the amount of debug information generated by the VM,
several command line options like "-d <x>" are avaliable. Usually,
different debug levels are possible:

  0 print nothing
  1 print basic debug info
  2 print more detailed debug info
  etc.


Some encoder command line options
---------------------------------

fixed bit rate <x> bit/s
  -r <x>

bit reservoir with <x> bits, reservoir initially filled
  -b <x>

bit reservoir with <x> bits, reservoir initially empty
  -b <x> -bi 0

variable bit rate, max <x> bit/s (burst rate)
(NOTE: the last frame is filled with padding bits
       to allow end_of_bitstream detection in decoder)
  -r <x> -vr

don't write ASCII info string to bit stream file
  -ni

disable MPEG4 header, use NBC magic string
  -nh -ms nbc3


Some decoder command line options
---------------------------------

test bit stream (not available for variable bit rate)
  -t


Audio file formats
------------------

Audio file I/O of the VM software is handled by the AFsp package. It
is available by FTP using the mpeg4ver account in the directory

  incoming/afsp/

or by aFTP in

  ftp://ftp.TSP.EE.McGill.CA/pub/AFsp/

Based on the AFsp package, the VM frame work can handle the following formats:

  .au        (also .snd)
  .aif       (also .aiff .aifc)
  .wav       (also .wave)
  .raw       (see $MP4_RAWAUDIOFILE)

To specify the format of raw audio input files, use the
$MP4_RAWAUDIOFILE environment variable as described in the AFsp
package. To select 16 bit integer raw files with a header length of 0
Bytes at 8000.0 Hz sampling, having native byte order, 1 channel
(i.e. mono) and a gain factor of 1.0, use

  setenv MP4_RAWAUDIOFILE "integer16, 0, 8000.0, native, 1, 1.0"

The format of audio output files is always integer16. Raw files are
written with native byte order.


end of README_frame
