/**
* Constructs the Zend_Media_Mpeg_ABS class with given file and options.
*
* The following options are currently recognized:
* o readmode -- Can be one of full or lazy and determines when the read
* of frames and their data happens. When in full mode the data is read
* automatically during the instantiation of the frame and all the
* frames are read during the instantiation of this class. While this
* allows faster validation and data fetching, it is unnecessary in
* terms of determining just the play duration of the file. Defaults to
* lazy.
*
* o estimatePrecision -- Only applicaple with lazy read mode to determine
* the precision of play duration estimate. This precision is equal to
* how many frames are read before fixing the average bitrate that is
* used to calculate the play duration estimate of the whole file. Each
* frame adds about 0.1-0.2ms to the processing of the file. Defaults to
* 1000.
*
* When in lazy data reading mode it is first checked whether a VBR header
* is found in a file. If so, the play duration is calculated based no its
* data and no further frames are read from the file. If no VBR header is
* found, frames up to estimatePrecision are read to calculate an average
* bitrate.
*
* Hence, only zero or <var>estimatePrecision</var> number of frames are
* read in lazy data reading mode. The rest of the frames are read
* automatically when directly referenced, ie the data is read when it is
* needed.
*
* @param string|resource|Zend_Io_Reader $filename The path to the file,
* file descriptor of an opened file, or a {@link Zend_Io_Reader} instance.
* @param Array $options The options array.
*/
public function __construct($filename, $options = array())
{
if ($filename instanceof Zend_Io_Reader) {
$this->_reader =& $filename;
} else {
try {
$this->_reader = new Zend_Io_FileReader($filename);
} catch (Zend_Io_Exception $e) {
$this->_reader = null;
throw new Zend_Media_Mpeg_Exception($e->getMessage());
}
}
$this->setOptions($options);
$offset = $this->_reader->getOffset();
$this->_bytes = $this->_reader->getSize();
/* Skip ID3v1 tag */
$this->_reader->setOffset(-128);
if ($this->_reader->read(3) == 'TAG') {
$this->_bytes -= 128;
}
$this->_reader->setOffset($offset);
/* Skip ID3v2 tags (some files errorneusly contain multiple tags) */
while ($this->_reader->readString8(3) == 'ID3') {
$header = new Zend_Media_Id3_Header($this->_reader);
$this->_reader->skip($header->getSize() + ($header->hasFlag(Zend_Media_Id3_Header::FOOTER) ? 10 : 0));
$offset = $this->_reader->getOffset();
}
$this->_reader->setOffset($offset);
/* Check whether the ABS is contained within a RIFF chunk */
$offset = $this->_reader->getOffset();
if ($this->_reader->readString8(4) == 'RIFF') {
$riffSize = $this->_reader->readUInt32LE();
$riffType = $this->_reader->read(4);
// WAVE
while ($this->_reader->getOffset() < $offset + 8 + $riffSize - 1) {
$chunkId = $this->_reader->read(4);
$chunkSize = $this->_reader->readUInt32LE();
if ($chunkId == 'fmt ') {
if ($this->_reader->readInt16LE() != 85) {
// 85: MPEG-1 Layer 3 Codec
throw new Zend_Media_Mpeg_Exception('File does not contain a valid MPEG Audio Bit Stream (Contains RIFF with no MPEG ABS)');
} else {
$this->_reader->skip($chunkSize - 2);
}
} else {
if ($chunkId == 'data') {
$offset = $this->_reader->getOffset();
break;
} else {
$this->_reader->skip($chunkSize);
}
}
}
} else {
$this->_reader->setOffset($offset);
}
/* Check for VBR headers */
$this->_frames[] = $firstFrame = new Zend_Media_Mpeg_Abs_Frame($this->_reader, $options);
$offset = $this->_reader->getOffset();
$this->_reader->setOffset($firstFrame->getOffset() + 4 + self::$sidesizes[$firstFrame->getFrequencyType()][$firstFrame->getMode()]);
if (($xing = $this->_reader->readString8(4)) == 'Xing' || $xing == 'Info') {
$this->_xingHeader = new Zend_Media_Mpeg_Abs_XingHeader($this->_reader, $options);
if ($this->_reader->readString8(4) == 'LAME') {
$this->_lameHeader = new Zend_Media_Mpeg_Abs_LameHeader($this->_reader, $options);
}
// A header frame is not counted as an audio frame
array_pop($this->_frames);
}
$this->_reader->setOffset($firstFrame->getOffset() + 4 + 32);
if ($this->_reader->readString8(4) == 'VBRI') {
$this->_vbriHeader = new Zend_Media_Mpeg_Abs_VbriHeader($this->_reader, $options);
// A header frame is not counted as an audio frame
array_pop($this->_frames);
}
$this->_reader->setOffset($offset);
// Ensure we always have read at least one frame
if (empty($this->_frames)) {
$this->_readFrames(1);
}
/* Read necessary frames */
if ($this->getOption('readmode', 'lazy') == 'lazy') {
if ((($header = $this->_xingHeader) !== null || ($header = $this->_vbriHeader) !== null) && $header->getFrames() != 0) {
$this->_estimatedPlayDuration = $header->getFrames() * $firstFrame->getSamples() / $firstFrame->getSamplingFrequency();
if ($this->_lameHeader !== null) {
$this->_estimatedBitrate = $this->_lameHeader->getBitrate();
if ($this->_estimatedBitrate == 255) {
$this->_estimatedBitrate = round($this->_lameHeader->getMusicLength() / ($header->getFrames() * $firstFrame->getSamples() / $firstFrame->getSamplingFrequency()) / 1000 * 8);
}
} else {
$this->_estimatedBitrate = ($this->_bytes - $firstFrame->getOffset()) / $this->_estimatedPlayDuration / 1000 * 8;
}
} else {
$this->_readFrames($this->getOption('estimatePrecision', 1000));
$this->_estimatedBitrate = $this->_cumulativeBitrate / count($this->_frames);
$this->_estimatedPlayDuration = ($this->_bytes - $firstFrame->getOffset()) / ($this->_estimatedBitrate * 1000 / 8);
}
} else {
$this->_readFrames();
$this->_estimatedBitrate = $this->_cumulativeBitrate / count($this->_frames);
$this->_estimatedPlayDuration = $this->_cumulativePlayDuration;
}
}
/**
* Constructs the Zend_Media_Mpeg_ABS class with given file and options.
*
* The following options are currently recognized:
* o readmode -- Can be one of full or lazy and determines when the read
* of frames and their data happens. When in full mode the data is read
* automatically during the instantiation of the frame and all the
* frames are read during the instantiation of this class. While this
* allows faster validation and data fetching, it is unnecessary in
* terms of determining just the play duration of the file. Defaults to
* lazy.
*
* o estimatePrecision -- Only applicaple with lazy read mode to determine
* the precision of play duration estimate. This precision is equal to
* how many frames are read before fixing the average bitrate that is
* used to calculate the play duration estimate of the whole file. Each
* frame adds about 0.1-0.2ms to the processing of the file. Defaults to
* 1000.
*
* When in lazy data reading mode it is first checked whether a VBR header
* is found in a file. If so, the play duration is calculated based no its
* data and no further frames are read from the file. If no VBR header is
* found, frames up to estimatePrecision are read to calculate an average
* bitrate.
*
* Hence, only zero or <var>estimatePrecision</var> number of frames are
* read in lazy data reading mode. The rest of the frames are read
* automatically when directly referenced, ie the data is read when it is
* needed.
*
* @param string|resource|Zend_Io_Reader $filename The path to the file,
* file descriptor of an opened file, or a {@link Zend_Io_Reader} instance.
* @param Array $options The options array.
*/
public function __construct($filename, $options = array())
{
if ($filename instanceof Zend_Io_Reader) {
$this->_reader =& $filename;
} else {
require_once 'Zend/Io/FileReader.php';
try {
$this->_reader = new Zend_Io_FileReader($filename);
} catch (Zend_Io_Exception $e) {
$this->_reader = null;
require_once 'Zend/Media/Mpeg/Exception.php';
throw new Zend_Media_Mpeg_Exception($e->getMessage());
}
}
$this->setOptions($options);
$offset = $this->_reader->getOffset();
$this->_bytes = $this->_reader->getSize();
/* Skip ID3v1 tag */
$this->_reader->setOffset(-128);
if ($this->_reader->read(3) == 'TAG') {
$this->_bytes -= 128;
}
$this->_reader->setOffset($offset);
/* Skip ID3v2 tag */
if ($this->_reader->readString8(3) == 'ID3') {
require_once 'Zend/Media/Id3/Header.php';
$header = new Zend_Media_Id3_Header($this->_reader);
$this->_reader->skip($header->getSize() + ($header->hasFlag(Zend_Media_Id3_Header::FOOTER) ? 10 : 0));
} else {
$this->_reader->setOffset($offset);
}
/* Check for VBR headers */
$offset = $this->_reader->getOffset();
$this->_frames[] = $firstFrame = new Zend_Media_Mpeg_Abs_Frame($this->_reader, $options);
$postoffset = $this->_reader->getOffset();
$this->_reader->setOffset($offset + 4 + self::$sidesizes[$firstFrame->getFrequencyType()][$firstFrame->getMode()]);
if (($xing = $this->_reader->readString8(4)) == 'Xing' || $xing == 'Info') {
require_once 'Zend/Media/Mpeg/Abs/XingHeader.php';
$this->_xingHeader = new Zend_Media_Mpeg_Abs_XingHeader($this->_reader, $options);
if ($this->_reader->readString8(4) == 'LAME') {
require_once 'Zend/Media/Mpeg/Abs/LameHeader.php';
$this->_lameHeader = new Zend_Media_Mpeg_Abs_LameHeader($this->_reader, $options);
}
// A header frame is not counted as an audio frame
array_pop($this->_frames);
}
$this->_reader->setOffset($offset + 4 + 32);
if ($this->_reader->readString8(4) == 'VBRI') {
require_once 'Zend/Media/Mpeg/Abs/VbriHeader.php';
$this->_vbriHeader = new Zend_Media_Mpeg_Abs_VbriHeader($this->_reader, $options);
// A header frame is not counted as an audio frame
array_pop($this->_frames);
}
$this->_reader->setOffset($postoffset);
// Ensure we always have read at least one frame
if (empty($this->_frames)) {
$this->_readFrames(1);
}
/* Read necessary frames */
if ($this->getOption('readmode', 'lazy') == 'lazy') {
if (($header = $this->_xingHeader) !== null || ($header = $this->_vbriHeader) !== null) {
$this->_estimatedPlayDuration = $header->getFrames() * $firstFrame->getSamples() / $firstFrame->getSamplingFrequency();
if ($this->_lameHeader !== null) {
$this->_estimatedBitrate = $this->_lameHeader->getBitrate();
if ($this->_estimatedBitrate == 255) {
$this->_estimatedBitrate = round($this->_lameHeader->getMusicLength() / ($header->getFrames() * $firstFrame->getSamples() / $firstFrame->getSamplingFrequency()) / 1000 * 8);
}
} else {
$this->_estimatedBitrate = ($this->_bytes - $offset) / $this->_estimatedPlayDuration / 1000 * 8;
}
} else {
$this->_readFrames($this->getOption('estimatePrecision', 1000));
$this->_estimatedBitrate = $this->_cumulativeBitrate / count($this->_frames);
$this->_estimatedPlayDuration = ($this->_bytes - $offset) / ($this->_estimatedBitrate * 1000 / 8);
}
} else {
$this->_readFrames();
$this->_estimatedBitrate = $this->_cumulativeBitrate / count($this->_frames);
$this->_estimatedPlayDuration = $this->_cumulativePlayDuration;
}
}