|
package playtime;
use Exporter 'import';
@EXPORT_OK=qw(playtime);
use POSIX qw(SEEK_CUR SEEK_SET SEEK_END);
sub new{
my $class=shift;
my $type=ref $class || $class;
my $this={};
bless $this, $type;
return $this;
}
sub BigEndian2Int{
my $byte_word=shift;
my $signed=0;
my $int_value=0;
my $byte_wordlen=length($byte_word);
my @ttt=split(//,$byte_word,$byte_wordlen);
for(my $i=0;$i<$byte_wordlen;$i++){
my $tmp=256 ** ($byte_wordlen-1-$i);
$int_value +=ord($ttt[$i]) * $tmp;
}
if($signed == '1'){
my $sign_mask_bit = 0x80 << (8 * ($byte_wordlen - 1));
if ( $int_value & $sign_mask_bit) {
$int_value = 0 - ($int_value & ($sign_mask_bit - 1));
}
}
return $int_value;
}
sub playtime(){
my $this=shift;
my $filename=shift;
my $flv_data_length=(lstat $filename)[7];
my $flv_head;
my $record;
open(FD,"<:raw","$filename") || die "can't open $filename\n";
read(FD,$flv_head,9) || die "read $filename error\n";
seek(FD,5,SEEK_SET) || die "seek $filename failed\n";
read(FD,$record,4) || die "read $filename failed(2)\n";
my $frame_size_data_length=BigEndian2Int($record);
my $flv_header_frame_length=9;
if( $frame_size_data_length > $flv_header_frame_length){
seek(FD,$abc,SEEK_CUR);
}
my $duration=0;
while((tell(FD) + 1) < $flv_data_length){
my $this_tag_header;
read(FD,$this_tag_header,16);
my $data_length = BigEndian2Int(eval {substr($this_tag_header,5,3)});
my $timestamp = BigEndian2Int(eval {substr($this_tag_header,8,3)});
my $next_offset = tell(FD) - 1 + $data_length;
if($timestamp > $duration){
$duration = $timestamp;
}
seek(FD,$next_offset,SEEK_SET);
}
close(FD);
return $this->{'filename'}=$duration;
}
1;
__END__
=head1 NAME
playtime - grab *.flv playtime
=head1 SYNOPSIS
use playtime;
my $play=new playtime;
$play->playtime('yourdir/tmp.flv');
=head1 AUTHOR
| create by irror ([email protected]) |
| 2007-12-17 |
| v1.0 |
=cut
|
