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File: includes/getid3/module.audio.la.php

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  Classes of Karl Holz  >  WaldScan  >  includes/getid3/module.audio.la.php  >  Download  
File: includes/getid3/module.audio.la.php
Role: Auxiliary script
Content type: text/plain
Description: getID3 dependency
Class: WaldScan
Scan directories for files with certain extensions
Author: By
Last change:
Date: 2 years ago
Size: 9,349 bytes
 

Contents

Class file image Download
<?php
/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org> //
// available at http://getid3.sourceforge.net //
// or http://www.getid3.org //
/////////////////////////////////////////////////////////////////
// See readme.txt for more details //
/////////////////////////////////////////////////////////////////
// //
// module.audio.la.php //
// module for analyzing LA (LosslessAudio) audio files //
// dependencies: module.audio.riff.php //
// ///
/////////////////////////////////////////////////////////////////

getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio-video.riff.php', __FILE__, true);

class
getid3_la extends getid3_handler
{

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

       
$offset = 0;
       
fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);
       
$rawdata = fread($this->getid3->fp, $this->getid3->fread_buffer_size());

        switch (
substr($rawdata, $offset, 4)) {
            case
'LA02':
            case
'LA03':
            case
'LA04':
               
$info['fileformat'] = 'la';
               
$info['audio']['dataformat'] = 'la';
               
$info['audio']['lossless'] = true;

               
$info['la']['version_major'] = (int) substr($rawdata, $offset + 2, 1);
               
$info['la']['version_minor'] = (int) substr($rawdata, $offset + 3, 1);
               
$info['la']['version'] = (float) $info['la']['version_major'] + ($info['la']['version_minor'] / 10);
               
$offset += 4;

               
$info['la']['uncompressed_size'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
               
$offset += 4;
                if (
$info['la']['uncompressed_size'] == 0) {
                   
$info['error'][] = 'Corrupt LA file: uncompressed_size == zero';
                    return
false;
                }

               
$WAVEchunk = substr($rawdata, $offset, 4);
                if (
$WAVEchunk !== 'WAVE') {
                   
$info['error'][] = 'Expected "WAVE" ('.getid3_lib::PrintHexBytes('WAVE').') at offset '.$offset.', found "'.$WAVEchunk.'" ('.getid3_lib::PrintHexBytes($WAVEchunk).') instead.';
                    return
false;
                }
               
$offset += 4;

               
$info['la']['fmt_size'] = 24;
                if (
$info['la']['version'] >= 0.3) {

                   
$info['la']['fmt_size'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
                   
$info['la']['header_size'] = 49 + $info['la']['fmt_size'] - 24;
                   
$offset += 4;

                } else {

                   
// version 0.2 didn't support additional data blocks
                   
$info['la']['header_size'] = 41;

                }

               
$fmt_chunk = substr($rawdata, $offset, 4);
                if (
$fmt_chunk !== 'fmt ') {
                   
$info['error'][] = 'Expected "fmt " ('.getid3_lib::PrintHexBytes('fmt ').') at offset '.$offset.', found "'.$fmt_chunk.'" ('.getid3_lib::PrintHexBytes($fmt_chunk).') instead.';
                    return
false;
                }
               
$offset += 4;
               
$fmt_size = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
               
$offset += 4;

               
$info['la']['raw']['format'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
               
$offset += 2;

               
$info['la']['channels'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
               
$offset += 2;
                if (
$info['la']['channels'] == 0) {
                   
$info['error'][] = 'Corrupt LA file: channels == zero';
                        return
false;
                }

               
$info['la']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
               
$offset += 4;
                if (
$info['la']['sample_rate'] == 0) {
                   
$info['error'][] = 'Corrupt LA file: sample_rate == zero';
                        return
false;
                }

               
$info['la']['bytes_per_second'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
               
$offset += 4;
               
$info['la']['bytes_per_sample'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
               
$offset += 2;
               
$info['la']['bits_per_sample'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 2));
               
$offset += 2;

               
$info['la']['samples'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
               
$offset += 4;

               
$info['la']['raw']['flags'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 1));
               
$offset += 1;
               
$info['la']['flags']['seekable'] = (bool) ($info['la']['raw']['flags'] & 0x01);
                if (
$info['la']['version'] >= 0.4) {
                   
$info['la']['flags']['high_compression'] = (bool) ($info['la']['raw']['flags'] & 0x02);
                }

               
$info['la']['original_crc'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
               
$offset += 4;

               
// mikeŘbevin*de
                // Basically, the blocksize/seekevery are 61440/19 in La0.4 and 73728/16
                // in earlier versions. A seekpoint is added every blocksize * seekevery
                // samples, so 4 * int(totalSamples / (blockSize * seekEvery)) should
                // give the number of bytes used for the seekpoints. Of course, if seeking
                // is disabled, there are no seekpoints stored.
               
if ($info['la']['version'] >= 0.4) {
                   
$info['la']['blocksize'] = 61440;
                   
$info['la']['seekevery'] = 19;
                } else {
                   
$info['la']['blocksize'] = 73728;
                   
$info['la']['seekevery'] = 16;
                }

               
$info['la']['seekpoint_count'] = 0;
                if (
$info['la']['flags']['seekable']) {
                   
$info['la']['seekpoint_count'] = floor($info['la']['samples'] / ($info['la']['blocksize'] * $info['la']['seekevery']));

                    for (
$i = 0; $i < $info['la']['seekpoint_count']; $i++) {
                       
$info['la']['seekpoints'][] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
                       
$offset += 4;
                    }
                }

                if (
$info['la']['version'] >= 0.3) {

                   
// Following the main header information, the program outputs all of the
                    // seekpoints. Following these is what I called the 'footer start',
                    // i.e. the position immediately after the La audio data is finished.
                   
$info['la']['footerstart'] = getid3_lib::LittleEndian2Int(substr($rawdata, $offset, 4));
                   
$offset += 4;

                    if (
$info['la']['footerstart'] > $info['filesize']) {
                       
$info['warning'][] = 'FooterStart value points to offset '.$info['la']['footerstart'].' which is beyond end-of-file ('.$info['filesize'].')';
                       
$info['la']['footerstart'] = $info['filesize'];
                    }

                } else {

                   
// La v0.2 didn't have FooterStart value
                   
$info['la']['footerstart'] = $info['avdataend'];

                }

                if (
$info['la']['footerstart'] < $info['avdataend']) {
                    if (
$RIFFtempfilename = tempnam(GETID3_TEMP_DIR, 'id3')) {
                        if (
$RIFF_fp = fopen($RIFFtempfilename, 'w+b')) {
                           
$RIFFdata = 'WAVE';
                            if (
$info['la']['version'] == 0.2) {
                               
$RIFFdata .= substr($rawdata, 12, 24);
                            } else {
                               
$RIFFdata .= substr($rawdata, 16, 24);
                            }
                            if (
$info['la']['footerstart'] < $info['avdataend']) {
                               
fseek($this->getid3->fp, $info['la']['footerstart'], SEEK_SET);
                               
$RIFFdata .= fread($this->getid3->fp, $info['avdataend'] - $info['la']['footerstart']);
                            }
                           
$RIFFdata = 'RIFF'.getid3_lib::LittleEndian2String(strlen($RIFFdata), 4, false).$RIFFdata;
                           
fwrite($RIFF_fp, $RIFFdata, strlen($RIFFdata));
                           
fclose($RIFF_fp);

                           
$getid3_temp = new getID3();
                           
$getid3_temp->openfile($RIFFtempfilename);
                           
$getid3_riff = new getid3_riff($getid3_temp);
                           
$getid3_riff->Analyze();

                            if (empty(
$getid3_temp->info['error'])) {
                               
$info['riff'] = $getid3_temp->info['riff'];
                            } else {
                               
$info['warning'][] = 'Error parsing RIFF portion of La file: '.implode($getid3_temp->info['error']);
                            }
                            unset(
$getid3_temp, $getid3_riff);
                        }
                       
unlink($RIFFtempfilename);
                    }
                }

               
// $info['avdataoffset'] should be zero to begin with, but just in case it's not, include the addition anyway
               
$info['avdataend'] = $info['avdataoffset'] + $info['la']['footerstart'];
               
$info['avdataoffset'] = $info['avdataoffset'] + $offset;

               
//$info['la']['codec'] = RIFFwFormatTagLookup($info['la']['raw']['format']);
               
$info['la']['compression_ratio'] = (float) (($info['avdataend'] - $info['avdataoffset']) / $info['la']['uncompressed_size']);
               
$info['playtime_seconds'] = (float) ($info['la']['samples'] / $info['la']['sample_rate']) / $info['la']['channels'];
                if (
$info['playtime_seconds'] == 0) {
                   
$info['error'][] = 'Corrupt LA file: playtime_seconds == zero';
                    return
false;
                }

               
$info['audio']['bitrate'] = ($info['avdataend'] - $info['avdataoffset']) * 8 / $info['playtime_seconds'];
               
//$info['audio']['codec'] = $info['la']['codec'];
               
$info['audio']['bits_per_sample'] = $info['la']['bits_per_sample'];
                break;

            default:
                if (
substr($rawdata, $offset, 2) == 'LA') {
                   
$info['error'][] = 'This version of getID3() ['.$this->getid3->version().'] does not support LA version '.substr($rawdata, $offset + 2, 1).'.'.substr($rawdata, $offset + 3, 1).' which this appears to be - check http://getid3.sourceforge.net for updates.';
                } else {
                   
$info['error'][] = 'Not a LA (Lossless-Audio) file';
                }
                return
false;
                break;
        }

       
$info['audio']['channels'] = $info['la']['channels'];
       
$info['audio']['sample_rate'] = (int) $info['la']['sample_rate'];
       
$info['audio']['encoder'] = 'LA v'.$info['la']['version'];

        return
true;
    }

}


?>