#!/usr/bin/perl

use Video::Capture::V4l;
use Video::Capture::VBI;

package Decoder;

use Video::Capture::VBI;

# derive from videotext-decoder
use base 'Video::Capture::VBI::VT';

# just display the page
sub enter_page {
   my($self,$page)=@_;
   my $sub = $page->{ctrl} & VTX_SUB;

   #return unless $page->{page}>=0x110 && $page->{page}<=0x134;
   #return unless $page->{page}==0x150;
   my $x = join ("", map { $_ ne "" ? "*" : "-" } @{$page->{packet}});
   printf "Teletext page %02x / %04x ($x)\n", $page->{page}, $sub;
   #return unless $page->{page} == 0x1df;

   # now print the page
   for ($y=0; $y<25; $y++)
     {
       my $x = $page->{packet}[$y];
       print $x ? decode_ansi decode_vtpage $x : "","\n";
     }
}

sub enter_packet {
   my $packet = $_;
}

package main;

$vbi = new Video::Capture::V4l::VBI or die;

# the next line is optional (it enables buffering)
$vbi->backlog(25); # max. 1 second backlog (~900kB)

$inp_fd = fileno STDIN;
$vbi_fd = $vbi->fileno;

$vt = new Decoder;

print "Capturing VBI block. Make sure you have tuned in to a channel!\n";

for(;;) {
   my $r="";
   vec($r,$inp_fd,1)=1;
   vec($r,$vbi_fd,1)=1;
   select $r,undef,undef,0.04;
   $vt->feed(decode_field $vbi->field, VBI_VT) while $vbi->queued;
   if (vec($r,$inp_fd,1)) {
      #print "HI\n";
      #sleep 5;
   }
}