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lib/MHFS/Plugin/GetVideo.pm  view on Meta::CPAN

        $framecnt = unpack('C', substr($data, 0, 1, ''))+1;
        my $firstframessize = 0;
        for(my $i = 0; $i < ($framecnt-1); $i++) {
            my $fsize = 0;
            while(1) {
                my $val = unpack('C', substr($data, 0, 1, ''));
                $fsize += $val;
                last if($val < 255);
            }
            push @sizes, $fsize;
            $firstframessize += $fsize;
        }
        push @sizes, (length($data) - $firstframessize);
    }
    # EBML
    elsif($lacing == 0x6) {
        $framecnt = unpack('C', substr($data, 0, 1, ''))+1;
        my $last = read_and_parse_vint_from_buf(\$data);
        push @sizes, $last;
        my $sum = $last;
        for(my $i = 0; $i < ($framecnt - 2); $i++) {
            my $width;
            my $offset = read_and_parse_vint_from_buf(\$data, \$width);
            # multiple by 2^bitwidth - 1 (with adjusted bitwidth)
            my $desiredbits = (8 * $width) - ($width+1);
            my $subtract = (1 << $desiredbits) - 1;
            my $result = $offset - $subtract;
            $last += $result;
            say "offset $offset width $width factor: " . sprintf("0x%X ", $subtract) . "result $result evaled $last";
            push @sizes, $last;
            $sum += $last;
        }
        my $lastlast = length($data) - $sum;
        say "lastlast $lastlast";
        push @sizes, $lastlast;
    }
    # fixed
    elsif($lacing == 0x4) {
        $framecnt = unpack('C', substr($data, 0, 1, ''))+1;
        my $framesize = length($data) / $framecnt;
        for(my $i = 0; $i < $framecnt; $i++) {
            push @sizes, $framesize;
        }
    }
    # no lacing
    else {
        push @sizes, length($data);
    }

    return {
        'trackno' => $trackno,
        'rawts' => $rawts,
        'rawflag'  => $rawflag,
        'frame_lengths' => \@sizes,
        'data' => $data,
        'ts' => unpack('s>', $rawts)
    };
}

sub telmval {
    my ($track, $stringid) = @_;
    my $constname = "EBMLID_$stringid";
    my $id = __PACKAGE__->$constname;
    return $track->{$id}{'value'}  // $track->{$id}{'data'};
    #return $track->{"$stringid"}}{'value'} // $track->{$EBMLID->{$stringid}}{'data'};
}

sub trackno_is_audio {
    my ($tracks, $trackno) = @_;
    foreach my $track (@$tracks) {
        if(telmval($track, 'TrackNumber') == $trackno) {
            return telmval($track, 'TrackType') == 0x2;
        }
    }
    return undef;
}

sub flac_read_METADATA_BLOCK {
    my $fh = $_[0];
    my $type = \$_[1];
    my $done = \$_[2];
    my $buf;
    my $headread = read($fh, $buf, 4);
    ($headread && ($headread == 4)) or return undef;
    my ($blocktypelast, $sizehi, $sizemid, $sizelo) = unpack('CCCC',$buf);
    $$done = $blocktypelast & 0x80;
    $$type = $blocktypelast & 0x7F;
    my $size = ($sizehi << 16) | ($sizemid << 8) | ($sizelo);
    #say "islast $$done type $type size $size";
    $$type != 0x7F or return undef;
    my $tbuf;
    my $dataread = read($fh, $tbuf, $size);
    ($dataread && ($dataread == $size)) or return undef;
    $buf .= $tbuf;
    return \$buf;
}

sub flac_parseStreamInfo {
    # https://metacpan.org/source/DANIEL/Audio-FLAC-Header-2.4/Header.pm
    my ($buf) = @_;
    my $metaBinString = unpack('B144', $buf);

    my $x32 = 0 x 32;
    my $info = {};
    $info->{'MINIMUMBLOCKSIZE'} = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 0, 16), -32)));
    $info->{'MAXIMUMBLOCKSIZE'} = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 16, 16), -32)));
    $info->{'MINIMUMFRAMESIZE'} = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 32, 24), -32)));
    $info->{'MAXIMUMFRAMESIZE'} = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 56, 24), -32)));

    $info->{'SAMPLERATE'}       = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 80, 20), -32)));
    $info->{'NUMCHANNELS'}      = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 100, 3), -32))) + 1;
    $info->{'BITSPERSAMPLE'}    = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 103, 5), -32))) + 1;

    # Calculate total samples in two parts
    my $highBits = unpack('N', pack('B32', substr($x32 . substr($metaBinString, 108, 4), -32)));

    $info->{'TOTALSAMPLES'} = $highBits * 2 ** 32 +
            unpack('N', pack('B32', substr($x32 . substr($metaBinString, 112, 32), -32)));

    # Return the MD5 as a 32-character hexadecimal string
    $info->{'MD5CHECKSUM'} = unpack('H32',substr($buf, 18, 16));
    return $info;
}

sub flac_read_to_audio {