<?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));
$offset += 4;
// mikeØbevin*de
// Basically, the blocksize/seekevery are 61440/19 in La0.4 and 73728/16
// in earlier versions. A seekpoint is added every blocksize * seekevery
// samples, so 4 * int(totalSamples / (blockSize * seekEvery)) should
// give the number of bytes used for the seekpoints. Of course, if seeking
// is disabled, there are no seekpoints stored.
if ($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;
}
}
?>
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