#!/bin/bash
# dpgshow
# a small utility to preview dpg files
# Usage : dpgshow <file.dpg>
# License GNU GPL v2

# $1 : the file to preview

# first check the file exists, deps (bash ?, od, dd, mplayer)

# read some info from the header
#read -u 0 -n 4 TYPEFICH < "$1"
FPS=`od -j 9 -N 2 -t d2 "$1" | awk '{ printf $2 }'`
AUDSTART=`od -j 20 -N 4 -i "$1" | awk '{ printf $2 }'`
AUDLEN=`od -j 24 -N 4 -i "$1" | awk '{ printf $2 }'`
VIDSTART=`od -j 28 -N 4 -i "$1" | awk '{ printf $2 }'`
VIDLEN=`od -j 32 -N 4 -i "$1" | awk '{ printf $2 }'`
echo FPS=$FPS , AUDSTART=$AUDSTART , AUDLEN=$AUDLEN , VIDSTART=$VIDSTART , VIDLEN=$((VIDLEN+1))

# split $1 into two temp files.
dd if="$1" of=~/tmp/preview.mp2 skip=$AUDSTART ibs=1 count=$AUDLEN
dd if="$1" of=~/tmp/preview.m1v skip=$VIDSTART ibs=1 count=$((VIDLEN+1))

mplayer -fps $FPS ~/tmp/preview.m1v -audiofile ~/tmp/preview.mp2

#rm -f ~/tmp/preview.{m1v,mp2}