Au.php

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<?php

namespace GetId3\Module\Audio;

use GetId3\Handler\BaseHandler;
use GetId3\Lib\Helper;

//  available at http://getid3.sourceforge.net                 //
//            or http://www.getid3.org                         //
// See readme.txt for more details                             //
//                                                             //
// module.audio.au.php                                         //
// module for analyzing AU files                               //
// dependencies: NONE                                          //
//                                                            ///

class Au extends BaseHandler
{

    public function analyze()
    {
        $info = &$this->getid3->info;

        fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);
        $AUheader  = fread($this->getid3->fp, 8);

        $magic = '.snd';
        if (substr($AUheader, 0, 4) != $magic) {
            $info['error'][] = 'Expecting "'.Helper::PrintHexBytes($magic).'" (".snd") at offset '.$info['avdataoffset'].', found "'.Helper::PrintHexBytes(substr($AUheader, 0, 4)).'"';

            return false;
        }

        // shortcut
        $info['au'] = array();
        $thisfile_au        = &$info['au'];

        $info['fileformat']            = 'au';
        $info['audio']['dataformat']   = 'au';
        $info['audio']['bitrate_mode'] = 'cbr';
        $thisfile_au['encoding']               = 'ISO-8859-1';

        $thisfile_au['header_length']   = Helper::BigEndian2Int(substr($AUheader,  4, 4));
        $AUheader .= fread($this->getid3->fp, $thisfile_au['header_length'] - 8);
        $info['avdataoffset'] += $thisfile_au['header_length'];

        $thisfile_au['data_size']             = Helper::BigEndian2Int(substr($AUheader,  8, 4));
        $thisfile_au['data_format_id']        = Helper::BigEndian2Int(substr($AUheader, 12, 4));
        $thisfile_au['sample_rate']           = Helper::BigEndian2Int(substr($AUheader, 16, 4));
        $thisfile_au['channels']              = Helper::BigEndian2Int(substr($AUheader, 20, 4));
        $thisfile_au['comments']['comment'][] =                      trim(substr($AUheader, 24));

        $thisfile_au['data_format'] = $this->AUdataFormatNameLookup($thisfile_au['data_format_id']);
        $thisfile_au['used_bits_per_sample'] = $this->AUdataFormatUsedBitsPerSampleLookup($thisfile_au['data_format_id']);
        if ($thisfile_au['bits_per_sample'] = $this->AUdataFormatBitsPerSampleLookup($thisfile_au['data_format_id'])) {
            $info['audio']['bits_per_sample'] = $thisfile_au['bits_per_sample'];
        } else {
            unset($thisfile_au['bits_per_sample']);
        }

        $info['audio']['sample_rate']  = $thisfile_au['sample_rate'];
        $info['audio']['channels']     = $thisfile_au['channels'];

        if (($info['avdataoffset'] + $thisfile_au['data_size']) > $info['avdataend']) {
            $info['warning'][] = 'Possible truncated file - expecting "'.$thisfile_au['data_size'].'" bytes of audio data, only found '.($info['avdataend'] - $info['avdataoffset']).' bytes"';
        }

        $info['playtime_seconds'] = $thisfile_au['data_size'] / ($thisfile_au['sample_rate'] * $thisfile_au['channels'] * ($thisfile_au['used_bits_per_sample'] / 8));
        $info['audio']['bitrate'] = ($thisfile_au['data_size'] * 8) / $info['playtime_seconds'];

        return true;
    }

    public function AUdataFormatNameLookup($id)
    {
        static $AUdataFormatNameLookup = array(
            0  => 'unspecified format',
            1  => '8-bit mu-law',
            2  => '8-bit linear',
            3  => '16-bit linear',
            4  => '24-bit linear',
            5  => '32-bit linear',
            6  => 'floating-point',
            7  => 'double-precision float',
            8  => 'fragmented sampled data',
            9  => 'SUN_FORMAT_NESTED',
            10 => 'DSP program',
            11 => '8-bit fixed-point',
            12 => '16-bit fixed-point',
            13 => '24-bit fixed-point',
            14 => '32-bit fixed-point',

            16 => 'non-audio display data',
            17 => 'SND_FORMAT_MULAW_SQUELCH',
            18 => '16-bit linear with emphasis',
            19 => '16-bit linear with compression',
            20 => '16-bit linear with emphasis + compression',
            21 => 'Music Kit DSP commands',
            22 => 'SND_FORMAT_DSP_COMMANDS_SAMPLES',
            23 => 'CCITT g.721 4-bit ADPCM',
            24 => 'CCITT g.722 ADPCM',
            25 => 'CCITT g.723 3-bit ADPCM',
            26 => 'CCITT g.723 5-bit ADPCM',
            27 => 'A-Law 8-bit'
        );

        return (isset($AUdataFormatNameLookup[$id]) ? $AUdataFormatNameLookup[$id] : false);
    }

    public function AUdataFormatBitsPerSampleLookup($id)
    {
        static $AUdataFormatBitsPerSampleLookup = array(
            1  => 8,
            2  => 8,
            3  => 16,
            4  => 24,
            5  => 32,
            6  => 32,
            7  => 64,

            11 => 8,
            12 => 16,
            13 => 24,
            14 => 32,

            18 => 16,
            19 => 16,
            20 => 16,

            23 => 16,

            25 => 16,
            26 => 16,
            27 => 8
        );

        return (isset($AUdataFormatBitsPerSampleLookup[$id]) ? $AUdataFormatBitsPerSampleLookup[$id] : false);
    }

    public function AUdataFormatUsedBitsPerSampleLookup($id)
    {
        static $AUdataFormatUsedBitsPerSampleLookup = array(
            1  => 8,
            2  => 8,
            3  => 16,
            4  => 24,
            5  => 32,
            6  => 32,
            7  => 64,

            11 => 8,
            12 => 16,
            13 => 24,
            14 => 32,

            18 => 16,
            19 => 16,
            20 => 16,

            23 => 4,

            25 => 3,
            26 => 5,
            27 => 8,
        );

        return (isset($AUdataFormatUsedBitsPerSampleLookup[$id]) ? $AUdataFormatUsedBitsPerSampleLookup[$id] : false);
    }
}