/**
* Decode the stream header
* @access private
*/
function _decodeHeader()
{
fseek($this->_filePointer, $this->_streamList[0]['body_offset'], SEEK_SET);
// The first 8 characters should be "Speex ".
if (fread($this->_filePointer, 8) != 'Speex ') {
throw new PEAR_Exception("Stream is undecodable due to a malformed header.", OGG_ERROR_UNDECODABLE);
}
$this->_version = fread($this->_filePointer, 20);
$this->_header = File_Ogg::_readLittleEndian($this->_filePointer, array('speex_version_id' => 32, 'header_size' => 32, 'rate' => 32, 'mode' => 32, 'mode_bitstream_version' => 32, 'nb_channels' => 32, 'bitrate' => 32, 'frame_size' => 32, 'vbr' => 32, 'frames_per_packet' => 32, 'extra_headers' => 32, 'reserved1' => 32, 'reserved2' => 32));
$this->_header['speex_version'] = $this->_version;
}
function getMetadata( $image, $path ) {
$metadata = array( 'version' => self::METADATA_VERSION );
if ( !class_exists( 'File_Ogg' ) ) {
require( 'File/Ogg.php' );
}
try {
$f = new File_Ogg( $path );
$streams = array();
foreach ( $f->listStreams() as $streamIDs ) {
foreach ( $streamIDs as $streamID ) {
$stream = $f->getStream( $streamID );
$streams[$streamID] = array(
'serial' => $stream->getSerial(),
'group' => $stream->getGroup(),
'type' => $stream->getType(),
'vendor' => $stream->getVendor(),
'length' => $stream->getLength(),
'size' => $stream->getSize(),
'header' => $stream->getHeader(),
'comments' => $stream->getComments()
);
}
}
$metadata['streams'] = $streams;
$metadata['length'] = $f->getLength();
// Get the offset of the file (in cases where the file is a segment copy)
$metadata['offset'] = $f->getStartOffset();
} catch ( PEAR_Exception $e ) {
// File not found, invalid stream, etc.
$metadata['error'] = array(
'message' => $e->getMessage(),
'code' => $e->getCode()
);
}
return serialize( $metadata );
}
/**
* Parse the identification header (the first of three headers) in a Vorbis stream.
*
* This function parses the identification header. The identification header
* contains simple audio characteristics, such as sample rate and number of
* channels. There are a number of error-checking provisions laid down in the Vorbis
* specification to ensure the stream is pure.
*
* @access private
*/
function _decodeIdentificationHeader()
{
$this->_decodeCommonHeader(OGG_VORBIS_IDENTIFICATION_HEADER, OGG_VORBIS_IDENTIFICATION_PAGE_OFFSET);
$h = File_Ogg::_readLittleEndian($this->_filePointer, array('vorbis_version' => 32, 'audio_channels' => 8, 'audio_sample_rate' => 32, 'bitrate_maximum' => 32, 'bitrate_nominal' => 32, 'bitrate_minimum' => 32, 'blocksize_0' => 4, 'blocksize_1' => 4, 'framing_flag' => 1));
// The Vorbis stream version must be 0.
if ($h['vorbis_version'] == 0) {
$this->_version = $h['vorbis_version'];
} else {
throw new PEAR_Exception("Stream is undecodable due to an invalid vorbis stream version.", OGG_VORBIS_ERROR_UNDECODABLE);
}
// The number of channels MUST be greater than 0.
if ($h['audio_channels'] == 0) {
throw new PEAR_Exception("Stream is undecodable due to zero channels.", OGG_VORBIS_ERROR_UNDECODABLE);
} else {
$this->_channels = $h['audio_channels'];
}
// The sample rate MUST be greater than 0.
if ($h['audio_sample_rate'] == 0) {
throw new PEAR_Exception("Stream is undecodable due to a zero sample rate.", OGG_VORBIS_ERROR_UNDECODABLE);
} else {
$this->_sampleRate = $h['audio_sample_rate'];
}
// Extract the various bitrates
$this->_maxBitrate = $h['bitrate_maximum'];
$this->_nomBitrate = $h['bitrate_nominal'];
$this->_minBitrate = $h['bitrate_minimum'];
// Powers of two between 6 and 13 inclusive.
$valid_block_sizes = array(64, 128, 256, 512, 1024, 2048, 4096, 8192);
// blocksize_0 MUST be a valid blocksize.
$blocksize_0 = pow(2, $h['blocksize_0']);
if (FALSE == in_array($blocksize_0, $valid_block_sizes)) {
throw new PEAR_Exception("Stream is undecodable because blocksize_0 is {$blocksize_0}, which is not a valid size.", OGG_VORBIS_ERROR_UNDECODABLE);
}
// Extract bits 5 to 8 from the character data.
// blocksize_1 MUST be a valid blocksize.
$blocksize_1 = pow(2, $h['blocksize_1']);
if (FALSE == in_array($blocksize_1, $valid_block_sizes)) {
throw new PEAR_Exception("Stream is undecodable because blocksize_1 is not a valid size.", OGG_VORBIS_ERROR_UNDECODABLE);
}
// blocksize 0 MUST be less than or equal to blocksize 1.
if ($blocksize_0 > $blocksize_1) {
throw new PEAR_Exception("Stream is undecodable because blocksize_0 is not less than or equal to blocksize_1.", OGG_VORBIS_ERROR_UNDECODABLE);
}
// The framing bit MUST be set to mark the end of the identification header.
// Some encoders are broken though -- TS
/*
if ($h['framing_flag'] == 0)
throw new PEAR_Exception("Stream in undecodable because the framing bit is not non-zero.", OGG_VORBIS_ERROR_UNDECODABLE);
*/
$this->_idHeader = $h;
}
function _decodeCommentsHeader()
{
fseek($this->_filePointer, $this->_streamData['pages'][1]['body_offset'], SEEK_SET);
$blockHeader = File_Ogg::_readBigEndian($this->_filePointer, array('last_block' => 1, 'block_type' => 7, 'length' => 24));
if ($blockHeader['block_type'] != 4) {
throw new PEAR_Exception("Stream Undecodable", OGG_ERROR_UNDECODABLE);
}
$this->_decodeBareCommentsHeader();
}
/**
* Parse the identification header in a Theora stream.
* @access private
*/
function _decodeIdentificationHeader()
{
$this->_decodeCommonHeader(OGG_THEORA_IDENTIFICATION_HEADER, OGG_THEORA_IDENTIFICATION_PAGE_OFFSET);
$h = File_Ogg::_readBigEndian($this->_filePointer, array('VMAJ' => 8, 'VMIN' => 8, 'VREV' => 8, 'FMBW' => 16, 'FMBH' => 16, 'PICW' => 24, 'PICH' => 24, 'PICX' => 8, 'PICY' => 8, 'FRN' => 32, 'FRD' => 32, 'PARN' => 24, 'PARD' => 24, 'CS' => 8, 'NOMBR' => 24, 'QUAL' => 6, 'KFGSHIFT' => 5, 'PF' => 2));
if (!$h) {
throw new PEAR_Exception("Stream is undecodable due to a truncated header.", OGG_ERROR_UNDECODABLE);
}
// Theora version
// Seems overly strict but this is what the spec says
// VREV is for backwards-compatible changes, apparently
if ($h['VMAJ'] != 3 || $h['VMIN'] != 2) {
throw new PEAR_Exception("Stream is undecodable due to an invalid theora version.", OGG_ERROR_UNDECODABLE);
}
$this->_theoraVersion = "{$h['VMAJ']}.{$h['VMIN']}.{$h['VREV']}";
// Frame height/width
if (!$h['FMBW'] || !$h['FMBH']) {
throw new PEAR_Exception("Stream is undecodable because it has frame size of zero.", OGG_ERROR_UNDECODABLE);
}
$this->_frameWidth = $h['FMBW'] * 16;
$this->_frameHeight = $h['FMBH'] * 16;
// Picture height/width
if ($h['PICW'] > $this->_frameWidth || $h['PICH'] > $this->_frameHeight) {
throw new PEAR_Exception("Stream is undecodable because the picture width is greater than the frame width.", OGG_ERROR_UNDECODABLE);
}
$this->_pictureWidth = $h['PICW'];
$this->_pictureHeight = $h['PICH'];
// Picture offset
$this->_offsetX = $h['PICX'];
$this->_offsetY = $h['PICY'];
// Frame rate
$this->_frameRate = $h['FRD'] == 0 ? 0 : $h['FRN'] / $h['FRD'];
// Physical aspect ratio
if (!$h['PARN'] || !$h['PARD']) {
$this->_physicalAspectRatio = 1;
} else {
$this->_physicalAspectRatio = $h['PARN'] / $h['PARD'];
}
// Color space
$colorSpaces = array(0 => 'Undefined', 1 => 'Rec. 470M', 2 => 'Rec. 470BG');
if (isset($colorSpaces[$h['CS']])) {
$this->_colorSpace = $colorSpaces[$h['CS']];
} else {
$this->_colorSpace = 'Unknown (reserved)';
}
$this->_nomBitrate = $h['NOMBR'];
$this->_quality = $h['QUAL'];
$this->_kfgShift = $h['KFGSHIFT'];
$pixelFormats = array(0 => '4:2:0', 1 => 'Unknown (reserved)', 2 => '4:2:2', 3 => '4:4:4');
$this->_pixelFormat = $pixelFormats[$h['PF']];
switch ($h['PF']) {
case 0:
$h['NSBS'] = floor(($h['FMBW'] + 1) / 2) * floor(($h['FMBH'] + 1) / 2) + 2 * floor(($h['FMBW'] + 3) / 4) * floor(($h['FMBH'] + 3) / 4);
$h['NBS'] = 6 * $h['FMBW'] * $h['FMBH'];
break;
case 2:
$h['NSBS'] = floor(($h['FMBW'] + 1) / 2) * floor(($h['FMBH'] + 1) / 2) + 2 * floor(($h['FMBW'] + 3) / 4) * floor(($h['FMBH'] + 1) / 2);
$h['NBS'] = 8 * $h['FMBW'] * $h['FMBH'];
break;
case 3:
$h['NSBS'] = 3 * floor(($h['FMBW'] + 1) / 2) * floor(($h['FMBH'] + 1) / 2);
$h['NBS'] = 12 * $h['FMBW'] * $h['FMBH'];
break;
default:
$h['NSBS'] = $h['NBS'] = 0;
}
$h['NMBS'] = $h['FMBW'] * $h['FMBH'];
$this->_idHeader = $h;
}
function loadMeta()
{
//load from the file:
if (is_file($this->oggPath . OGGCHOP_META_EXT)) {
$oggMeta = file_get_contents($this->oggPath . OGGCHOP_META_EXT);
//check if a separate request is working on generating the file:
if (trim($oggMeta) == 'loading') {
if ($this->loadWaitCount >= 24) {
//we have waited 2 min with no luck..
//@@todo we should flag that ogg file as broken?
// and just redirect to normal output? (for now just set meta to false)
$this->meta = false;
//fail:
return false;
} else {
//some other request is "loading" metadata sleep for 5 seconds and try again
sleep(5);
$this->loadWaitCount++;
return $this->loadMeta();
}
} else {
$this->meta = unserialize($oggMeta);
if ($this->meta['version'] == 'OGGCHOP_META_VERSION') {
//we have a good version of the metadata return true:
return true;
} else {
$this->meta = false;
}
}
}
//if the file does not exist or $this->meta is still false::
if (!is_file($this->oggPath . OGGCHOP_META_EXT) || $this->meta === false) {
//set the meta file to "loading" (avoids multiple indexing requests)
file_put_contents($this->oggPath . OGGCHOP_META_EXT, 'loading');
//load up the File/Ogg Pear module
if (!class_exists('File_Ogg')) {
require 'File/Ogg.php';
}
$f = new File_Ogg($this->oggPath);
$streams = array();
$this->meta = array('version' => OGGCHOP_META_VERSION);
foreach ($f->listStreams() as $streamType => $streamIDs) {
foreach ($streamIDs as $streamID) {
$stream = $f->getStream($streamID);
//for now only support a fist theora stream we find:
if (strtolower($stream->getType()) == 'theora') {
$this->meta['theoraKeyFrameInx'] = $stream->getKeyFrameIndex();
//set the width and height:
$head = $stream->getHeader();
$this->meta['width'] = $head['PICW'];
$this->meta['height'] = $head['PICH'];
break;
}
/* more detailed per-stream metadata::
* $this->meta['streams'][$streamID] = array(
'serial' => $stream->getSerial(),
'group' => $stream->getGroup(),
'type' => $stream->getType(),
'vendor' => $stream->getVendor(),
'length' => $stream->getLength(),
'size' => $stream->getSize(),
'header' => $stream->getHeader(),
'comments' => $stream->getComments()
);*/
}
}
$this->meta['duration'] = $f->getLength();
//cache the metadata::
file_put_contents($this->oggPath . OGGCHOP_META_EXT, serialize($this->meta));
return true;
}
}
