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Direktori : /proc/thread-self/cwd/ID3/ |
Current File : //proc/thread-self/cwd/ID3/module.audio-video.flv.php |
<?php ///////////////////////////////////////////////////////////////// /// getID3() by James Heinrich <info@getid3.org> // // available at https://github.com/JamesHeinrich/getID3 // // or https://www.getid3.org // // or http://getid3.sourceforge.net // // see readme.txt for more details // ///////////////////////////////////////////////////////////////// // // // module.audio-video.flv.php // // module for analyzing Shockwave Flash Video files // // dependencies: NONE // // // ///////////////////////////////////////////////////////////////// // // // FLV module by Seth Kaufman <sethØwhirl-i-gig*com> // // // // * version 0.1 (26 June 2005) // // // // * version 0.1.1 (15 July 2005) // // minor modifications by James Heinrich <info@getid3.org> // // // // * version 0.2 (22 February 2006) // // Support for On2 VP6 codec and meta information // // by Steve Webster <steve.websterØfeaturecreep*com> // // // // * version 0.3 (15 June 2006) // // Modified to not read entire file into memory // // by James Heinrich <info@getid3.org> // // // // * version 0.4 (07 December 2007) // // Bugfixes for incorrectly parsed FLV dimensions // // and incorrect parsing of onMetaTag // // by Evgeny Moysevich <moysevichØgmail*com> // // // // * version 0.5 (21 May 2009) // // Fixed parsing of audio tags and added additional codec // // details. The duration is now read from onMetaTag (if // // exists), rather than parsing whole file // // by Nigel Barnes <ngbarnesØhotmail*com> // // // // * version 0.6 (24 May 2009) // // Better parsing of files with h264 video // // by Evgeny Moysevich <moysevichØgmail*com> // // // // * version 0.6.1 (30 May 2011) // // prevent infinite loops in expGolombUe() // // // // * version 0.7.0 (16 Jul 2013) // // handle GETID3_FLV_VIDEO_VP6FLV_ALPHA // // improved AVCSequenceParameterSetReader::readData() // // by Xander Schouwerwou <schouwerwouØgmail*com> // // /// ///////////////////////////////////////////////////////////////// if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers exit; } define('GETID3_FLV_TAG_AUDIO', 8); define('GETID3_FLV_TAG_VIDEO', 9); define('GETID3_FLV_TAG_META', 18); define('GETID3_FLV_VIDEO_H263', 2); define('GETID3_FLV_VIDEO_SCREEN', 3); define('GETID3_FLV_VIDEO_VP6FLV', 4); define('GETID3_FLV_VIDEO_VP6FLV_ALPHA', 5); define('GETID3_FLV_VIDEO_SCREENV2', 6); define('GETID3_FLV_VIDEO_H264', 7); define('H264_AVC_SEQUENCE_HEADER', 0); define('H264_PROFILE_BASELINE', 66); define('H264_PROFILE_MAIN', 77); define('H264_PROFILE_EXTENDED', 88); define('H264_PROFILE_HIGH', 100); define('H264_PROFILE_HIGH10', 110); define('H264_PROFILE_HIGH422', 122); define('H264_PROFILE_HIGH444', 144); define('H264_PROFILE_HIGH444_PREDICTIVE', 244); class getid3_flv extends getid3_handler { const magic = 'FLV'; /** * Break out of the loop if too many frames have been scanned; only scan this * many if meta frame does not contain useful duration. * * @var int */ public $max_frames = 100000; /** * @return bool */ public function Analyze() { $info = &$this->getid3->info; $this->fseek($info['avdataoffset']); $FLVdataLength = $info['avdataend'] - $info['avdataoffset']; $FLVheader = $this->fread(5); $info['fileformat'] = 'flv'; $info['flv']['header']['signature'] = substr($FLVheader, 0, 3); $info['flv']['header']['version'] = getid3_lib::BigEndian2Int(substr($FLVheader, 3, 1)); $TypeFlags = getid3_lib::BigEndian2Int(substr($FLVheader, 4, 1)); if ($info['flv']['header']['signature'] != self::magic) { $this->error('Expecting "'.getid3_lib::PrintHexBytes(self::magic).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes($info['flv']['header']['signature']).'"'); unset($info['flv'], $info['fileformat']); return false; } $info['flv']['header']['hasAudio'] = (bool) ($TypeFlags & 0x04); $info['flv']['header']['hasVideo'] = (bool) ($TypeFlags & 0x01); $FrameSizeDataLength = getid3_lib::BigEndian2Int($this->fread(4)); $FLVheaderFrameLength = 9; if ($FrameSizeDataLength > $FLVheaderFrameLength) { $this->fseek($FrameSizeDataLength - $FLVheaderFrameLength, SEEK_CUR); } $Duration = 0; $found_video = false; $found_audio = false; $found_meta = false; $found_valid_meta_playtime = false; $tagParseCount = 0; $info['flv']['framecount'] = array('total'=>0, 'audio'=>0, 'video'=>0); $flv_framecount = &$info['flv']['framecount']; while ((($this->ftell() + 16) < $info['avdataend']) && (($tagParseCount++ <= $this->max_frames) || !$found_valid_meta_playtime)) { $ThisTagHeader = $this->fread(16); $PreviousTagLength = getid3_lib::BigEndian2Int(substr($ThisTagHeader, 0, 4)); $TagType = getid3_lib::BigEndian2Int(substr($ThisTagHeader, 4, 1)); $DataLength = getid3_lib::BigEndian2Int(substr($ThisTagHeader, 5, 3)); $Timestamp = getid3_lib::BigEndian2Int(substr($ThisTagHeader, 8, 3)); $LastHeaderByte = getid3_lib::BigEndian2Int(substr($ThisTagHeader, 15, 1)); $NextOffset = $this->ftell() - 1 + $DataLength; if ($Timestamp > $Duration) { $Duration = $Timestamp; } $flv_framecount['total']++; switch ($TagType) { case GETID3_FLV_TAG_AUDIO: $flv_framecount['audio']++; if (!$found_audio) { $found_audio = true; $info['flv']['audio']['audioFormat'] = ($LastHeaderByte >> 4) & 0x0F; $info['flv']['audio']['audioRate'] = ($LastHeaderByte >> 2) & 0x03; $info['flv']['audio']['audioSampleSize'] = ($LastHeaderByte >> 1) & 0x01; $info['flv']['audio']['audioType'] = $LastHeaderByte & 0x01; } break; case GETID3_FLV_TAG_VIDEO: $flv_framecount['video']++; if (!$found_video) { $found_video = true; $info['flv']['video']['videoCodec'] = $LastHeaderByte & 0x07; $FLVvideoHeader = $this->fread(11); $PictureSizeEnc = array(); if ($info['flv']['video']['videoCodec'] == GETID3_FLV_VIDEO_H264) { // this code block contributed by: moysevichØgmail*com $AVCPacketType = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 0, 1)); if ($AVCPacketType == H264_AVC_SEQUENCE_HEADER) { // read AVCDecoderConfigurationRecord $configurationVersion = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 4, 1)); $AVCProfileIndication = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 5, 1)); $profile_compatibility = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 6, 1)); $lengthSizeMinusOne = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 7, 1)); $numOfSequenceParameterSets = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 8, 1)); if (($numOfSequenceParameterSets & 0x1F) != 0) { // there is at least one SequenceParameterSet // read size of the first SequenceParameterSet //$spsSize = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 9, 2)); $spsSize = getid3_lib::LittleEndian2Int(substr($FLVvideoHeader, 9, 2)); // read the first SequenceParameterSet $sps = $this->fread($spsSize); if (strlen($sps) == $spsSize) { // make sure that whole SequenceParameterSet was red $spsReader = new AVCSequenceParameterSetReader($sps); $spsReader->readData(); $info['video']['resolution_x'] = $spsReader->getWidth(); $info['video']['resolution_y'] = $spsReader->getHeight(); } } } // end: moysevichØgmail*com } elseif ($info['flv']['video']['videoCodec'] == GETID3_FLV_VIDEO_H263) { $PictureSizeType = (getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 3, 2))) >> 7; $PictureSizeType = $PictureSizeType & 0x0007; $info['flv']['header']['videoSizeType'] = $PictureSizeType; switch ($PictureSizeType) { case 0: //$PictureSizeEnc = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 5, 2)); //$PictureSizeEnc <<= 1; //$info['video']['resolution_x'] = ($PictureSizeEnc & 0xFF00) >> 8; //$PictureSizeEnc = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 6, 2)); //$PictureSizeEnc <<= 1; //$info['video']['resolution_y'] = ($PictureSizeEnc & 0xFF00) >> 8; $PictureSizeEnc['x'] = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 4, 2)) >> 7; $PictureSizeEnc['y'] = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 5, 2)) >> 7; $info['video']['resolution_x'] = $PictureSizeEnc['x'] & 0xFF; $info['video']['resolution_y'] = $PictureSizeEnc['y'] & 0xFF; break; case 1: $PictureSizeEnc['x'] = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 4, 3)) >> 7; $PictureSizeEnc['y'] = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 6, 3)) >> 7; $info['video']['resolution_x'] = $PictureSizeEnc['x'] & 0xFFFF; $info['video']['resolution_y'] = $PictureSizeEnc['y'] & 0xFFFF; break; case 2: $info['video']['resolution_x'] = 352; $info['video']['resolution_y'] = 288; break; case 3: $info['video']['resolution_x'] = 176; $info['video']['resolution_y'] = 144; break; case 4: $info['video']['resolution_x'] = 128; $info['video']['resolution_y'] = 96; break; case 5: $info['video']['resolution_x'] = 320; $info['video']['resolution_y'] = 240; break; case 6: $info['video']['resolution_x'] = 160; $info['video']['resolution_y'] = 120; break; default: $info['video']['resolution_x'] = 0; $info['video']['resolution_y'] = 0; break; } } elseif ($info['flv']['video']['videoCodec'] == GETID3_FLV_VIDEO_VP6FLV_ALPHA) { /* contributed by schouwerwouØgmail*com */ if (!isset($info['video']['resolution_x'])) { // only when meta data isn't set $PictureSizeEnc['x'] = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 6, 2)); $PictureSizeEnc['y'] = getid3_lib::BigEndian2Int(substr($FLVvideoHeader, 7, 2)); $info['video']['resolution_x'] = ($PictureSizeEnc['x'] & 0xFF) << 3; $info['video']['resolution_y'] = ($PictureSizeEnc['y'] & 0xFF) << 3; } /* end schouwerwouØgmail*com */ } if (!empty($info['video']['resolution_x']) && !empty($info['video']['resolution_y'])) { $info['video']['pixel_aspect_ratio'] = $info['video']['resolution_x'] / $info['video']['resolution_y']; } } break; // Meta tag case GETID3_FLV_TAG_META: if (!$found_meta) { $found_meta = true; $this->fseek(-1, SEEK_CUR); $datachunk = $this->fread($DataLength); $AMFstream = new AMFStream($datachunk); $reader = new AMFReader($AMFstream); $eventName = $reader->readData(); $info['flv']['meta'][$eventName] = $reader->readData(); unset($reader); $copykeys = array('framerate'=>'frame_rate', 'width'=>'resolution_x', 'height'=>'resolution_y', 'audiodatarate'=>'bitrate', 'videodatarate'=>'bitrate'); foreach ($copykeys as $sourcekey => $destkey) { if (isset($info['flv']['meta']['onMetaData'][$sourcekey])) { switch ($sourcekey) { case 'width': case 'height': $info['video'][$destkey] = intval(round($info['flv']['meta']['onMetaData'][$sourcekey])); break; case 'audiodatarate': $info['audio'][$destkey] = getid3_lib::CastAsInt(round($info['flv']['meta']['onMetaData'][$sourcekey] * 1000)); break; case 'videodatarate': case 'frame_rate': default: $info['video'][$destkey] = $info['flv']['meta']['onMetaData'][$sourcekey]; break; } } } if (!empty($info['flv']['meta']['onMetaData']['duration'])) { $found_valid_meta_playtime = true; } } break; default: // noop break; } $this->fseek($NextOffset); } $info['playtime_seconds'] = $Duration / 1000; if ($info['playtime_seconds'] > 0) { $info['bitrate'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds']; } if ($info['flv']['header']['hasAudio']) { $info['audio']['codec'] = self::audioFormatLookup($info['flv']['audio']['audioFormat']); $info['audio']['sample_rate'] = self::audioRateLookup($info['flv']['audio']['audioRate']); $info['audio']['bits_per_sample'] = self::audioBitDepthLookup($info['flv']['audio']['audioSampleSize']); $info['audio']['channels'] = $info['flv']['audio']['audioType'] + 1; // 0=mono,1=stereo $info['audio']['lossless'] = ($info['flv']['audio']['audioFormat'] ? false : true); // 0=uncompressed $info['audio']['dataformat'] = 'flv'; } if (!empty($info['flv']['header']['hasVideo'])) { $info['video']['codec'] = self::videoCodecLookup($info['flv']['video']['videoCodec']); $info['video']['dataformat'] = 'flv'; $info['video']['lossless'] = false; } // Set information from meta if (!empty($info['flv']['meta']['onMetaData']['duration'])) { $info['playtime_seconds'] = $info['flv']['meta']['onMetaData']['duration']; $info['bitrate'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds']; } if (isset($info['flv']['meta']['onMetaData']['audiocodecid'])) { $info['audio']['codec'] = self::audioFormatLookup($info['flv']['meta']['onMetaData']['audiocodecid']); } if (isset($info['flv']['meta']['onMetaData']['videocodecid'])) { $info['video']['codec'] = self::videoCodecLookup($info['flv']['meta']['onMetaData']['videocodecid']); } return true; } /** * @param int $id * * @return string|false */ public static function audioFormatLookup($id) { static $lookup = array( 0 => 'Linear PCM, platform endian', 1 => 'ADPCM', 2 => 'mp3', 3 => 'Linear PCM, little endian', 4 => 'Nellymoser 16kHz mono', 5 => 'Nellymoser 8kHz mono', 6 => 'Nellymoser', 7 => 'G.711A-law logarithmic PCM', 8 => 'G.711 mu-law logarithmic PCM', 9 => 'reserved', 10 => 'AAC', 11 => 'Speex', 12 => false, // unknown? 13 => false, // unknown? 14 => 'mp3 8kHz', 15 => 'Device-specific sound', ); return (isset($lookup[$id]) ? $lookup[$id] : false); } /** * @param int $id * * @return int|false */ public static function audioRateLookup($id) { static $lookup = array( 0 => 5500, 1 => 11025, 2 => 22050, 3 => 44100, ); return (isset($lookup[$id]) ? $lookup[$id] : false); } /** * @param int $id * * @return int|false */ public static function audioBitDepthLookup($id) { static $lookup = array( 0 => 8, 1 => 16, ); return (isset($lookup[$id]) ? $lookup[$id] : false); } /** * @param int $id * * @return string|false */ public static function videoCodecLookup($id) { static $lookup = array( GETID3_FLV_VIDEO_H263 => 'Sorenson H.263', GETID3_FLV_VIDEO_SCREEN => 'Screen video', GETID3_FLV_VIDEO_VP6FLV => 'On2 VP6', GETID3_FLV_VIDEO_VP6FLV_ALPHA => 'On2 VP6 with alpha channel', GETID3_FLV_VIDEO_SCREENV2 => 'Screen video v2', GETID3_FLV_VIDEO_H264 => 'Sorenson H.264', ); return (isset($lookup[$id]) ? $lookup[$id] : false); } } class AMFStream { /** * @var string */ public $bytes; /** * @var int */ public $pos; /** * @param string $bytes */ public function __construct(&$bytes) { $this->bytes =& $bytes; $this->pos = 0; } /** * @return int */ public function readByte() { // 8-bit return ord(substr($this->bytes, $this->pos++, 1)); } /** * @return int */ public function readInt() { // 16-bit return ($this->readByte() << 8) + $this->readByte(); } /** * @return int */ public function readLong() { // 32-bit return ($this->readByte() << 24) + ($this->readByte() << 16) + ($this->readByte() << 8) + $this->readByte(); } /** * @return float|false */ public function readDouble() { return getid3_lib::BigEndian2Float($this->read(8)); } /** * @return string */ public function readUTF() { $length = $this->readInt(); return $this->read($length); } /** * @return string */ public function readLongUTF() { $length = $this->readLong(); return $this->read($length); } /** * @param int $length * * @return string */ public function read($length) { $val = substr($this->bytes, $this->pos, $length); $this->pos += $length; return $val; } /** * @return int */ public function peekByte() { $pos = $this->pos; $val = $this->readByte(); $this->pos = $pos; return $val; } /** * @return int */ public function peekInt() { $pos = $this->pos; $val = $this->readInt(); $this->pos = $pos; return $val; } /** * @return int */ public function peekLong() { $pos = $this->pos; $val = $this->readLong(); $this->pos = $pos; return $val; } /** * @return float|false */ public function peekDouble() { $pos = $this->pos; $val = $this->readDouble(); $this->pos = $pos; return $val; } /** * @return string */ public function peekUTF() { $pos = $this->pos; $val = $this->readUTF(); $this->pos = $pos; return $val; } /** * @return string */ public function peekLongUTF() { $pos = $this->pos; $val = $this->readLongUTF(); $this->pos = $pos; return $val; } } class AMFReader { /** * @var AMFStream */ public $stream; /** * @param AMFStream $stream */ public function __construct(AMFStream $stream) { $this->stream = $stream; } /** * @return mixed */ public function readData() { $value = null; $type = $this->stream->readByte(); switch ($type) { // Double case 0: $value = $this->readDouble(); break; // Boolean case 1: $value = $this->readBoolean(); break; // String case 2: $value = $this->readString(); break; // Object case 3: $value = $this->readObject(); break; // null case 6: return null; // Mixed array case 8: $value = $this->readMixedArray(); break; // Array case 10: $value = $this->readArray(); break; // Date case 11: $value = $this->readDate(); break; // Long string case 13: $value = $this->readLongString(); break; // XML (handled as string) case 15: $value = $this->readXML(); break; // Typed object (handled as object) case 16: $value = $this->readTypedObject(); break; // Long string default: $value = '(unknown or unsupported data type)'; break; } return $value; } /** * @return float|false */ public function readDouble() { return $this->stream->readDouble(); } /** * @return bool */ public function readBoolean() { return $this->stream->readByte() == 1; } /** * @return string */ public function readString() { return $this->stream->readUTF(); } /** * @return array */ public function readObject() { // Get highest numerical index - ignored // $highestIndex = $this->stream->readLong(); $data = array(); $key = null; while ($key = $this->stream->readUTF()) { $data[$key] = $this->readData(); } // Mixed array record ends with empty string (0x00 0x00) and 0x09 if (($key == '') && ($this->stream->peekByte() == 0x09)) { // Consume byte $this->stream->readByte(); } return $data; } /** * @return array */ public function readMixedArray() { // Get highest numerical index - ignored $highestIndex = $this->stream->readLong(); $data = array(); $key = null; while ($key = $this->stream->readUTF()) { if (is_numeric($key)) { $key = (int) $key; } $data[$key] = $this->readData(); } // Mixed array record ends with empty string (0x00 0x00) and 0x09 if (($key == '') && ($this->stream->peekByte() == 0x09)) { // Consume byte $this->stream->readByte(); } return $data; } /** * @return array */ public function readArray() { $length = $this->stream->readLong(); $data = array(); for ($i = 0; $i < $length; $i++) { $data[] = $this->readData(); } return $data; } /** * @return float|false */ public function readDate() { $timestamp = $this->stream->readDouble(); $timezone = $this->stream->readInt(); return $timestamp; } /** * @return string */ public function readLongString() { return $this->stream->readLongUTF(); } /** * @return string */ public function readXML() { return $this->stream->readLongUTF(); } /** * @return array */ public function readTypedObject() { $className = $this->stream->readUTF(); return $this->readObject(); } } class AVCSequenceParameterSetReader { /** * @var string */ public $sps; public $start = 0; public $currentBytes = 0; public $currentBits = 0; /** * @var int */ public $width; /** * @var int */ public $height; /** * @param string $sps */ public function __construct($sps) { $this->sps = $sps; } public function readData() { $this->skipBits(8); $this->skipBits(8); $profile = $this->getBits(8); // read profile if ($profile > 0) { $this->skipBits(8); $level_idc = $this->getBits(8); // level_idc $this->expGolombUe(); // seq_parameter_set_id // sps $this->expGolombUe(); // log2_max_frame_num_minus4 $picOrderType = $this->expGolombUe(); // pic_order_cnt_type if ($picOrderType == 0) { $this->expGolombUe(); // log2_max_pic_order_cnt_lsb_minus4 } elseif ($picOrderType == 1) { $this->skipBits(1); // delta_pic_order_always_zero_flag $this->expGolombSe(); // offset_for_non_ref_pic $this->expGolombSe(); // offset_for_top_to_bottom_field $num_ref_frames_in_pic_order_cnt_cycle = $this->expGolombUe(); // num_ref_frames_in_pic_order_cnt_cycle for ($i = 0; $i < $num_ref_frames_in_pic_order_cnt_cycle; $i++) { $this->expGolombSe(); // offset_for_ref_frame[ i ] } } $this->expGolombUe(); // num_ref_frames $this->skipBits(1); // gaps_in_frame_num_value_allowed_flag $pic_width_in_mbs_minus1 = $this->expGolombUe(); // pic_width_in_mbs_minus1 $pic_height_in_map_units_minus1 = $this->expGolombUe(); // pic_height_in_map_units_minus1 $frame_mbs_only_flag = $this->getBits(1); // frame_mbs_only_flag if ($frame_mbs_only_flag == 0) { $this->skipBits(1); // mb_adaptive_frame_field_flag } $this->skipBits(1); // direct_8x8_inference_flag $frame_cropping_flag = $this->getBits(1); // frame_cropping_flag $frame_crop_left_offset = 0; $frame_crop_right_offset = 0; $frame_crop_top_offset = 0; $frame_crop_bottom_offset = 0; if ($frame_cropping_flag) { $frame_crop_left_offset = $this->expGolombUe(); // frame_crop_left_offset $frame_crop_right_offset = $this->expGolombUe(); // frame_crop_right_offset $frame_crop_top_offset = $this->expGolombUe(); // frame_crop_top_offset $frame_crop_bottom_offset = $this->expGolombUe(); // frame_crop_bottom_offset } $this->skipBits(1); // vui_parameters_present_flag // etc $this->width = (($pic_width_in_mbs_minus1 + 1) * 16) - ($frame_crop_left_offset * 2) - ($frame_crop_right_offset * 2); $this->height = ((2 - $frame_mbs_only_flag) * ($pic_height_in_map_units_minus1 + 1) * 16) - ($frame_crop_top_offset * 2) - ($frame_crop_bottom_offset * 2); } } /** * @param int $bits */ public function skipBits($bits) { $newBits = $this->currentBits + $bits; $this->currentBytes += (int)floor($newBits / 8); $this->currentBits = $newBits % 8; } /** * @return int */ public function getBit() { $result = (getid3_lib::BigEndian2Int(substr($this->sps, $this->currentBytes, 1)) >> (7 - $this->currentBits)) & 0x01; $this->skipBits(1); return $result; } /** * @param int $bits * * @return int */ public function getBits($bits) { $result = 0; for ($i = 0; $i < $bits; $i++) { $result = ($result << 1) + $this->getBit(); } return $result; } /** * @return int */ public function expGolombUe() { $significantBits = 0; $bit = $this->getBit(); while ($bit == 0) { $significantBits++; $bit = $this->getBit(); if ($significantBits > 31) { // something is broken, this is an emergency escape to prevent infinite loops return 0; } } return (1 << $significantBits) + $this->getBits($significantBits) - 1; } /** * @return int */ public function expGolombSe() { $result = $this->expGolombUe(); if (($result & 0x01) == 0) { return -($result >> 1); } else { return ($result + 1) >> 1; } } /** * @return int */ public function getWidth() { return $this->width; } /** * @return int */ public function getHeight() { return $this->height; } }