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August 29, 2012 17:22
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RobThree revised this gist
Aug 30, 2012 . 1 changed file with 67 additions and 28 deletions.There are no files selected for viewing
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -13,7 +13,7 @@ */ class WaveFileReader { private static $HEADER_LENGTH = 44; //Header size is at least 44 bytes (and possibly more...) /** * ReadFile reads the headers (and optionally the data) from a wave file @@ -34,36 +34,61 @@ public static function ReadFile($filename, $readdata = false) { //Read the header and stuff all info in an array $handle = fopen($filename, 'rb'); $riff = array( 'chunkid' => self::readString($handle, 4), 'chunksize' => self::readLong($handle), 'format' => self::readString($handle, 4) ); $fmt = array( 'id' => self::readString($handle, 4), 'size' => self::readLong($handle), 'audioformat' => self::readWord($handle), 'numchannels' => self::readWord($handle), 'samplerate' => self::readLong($handle), 'byterate' => self::readLong($handle), 'blockalign' => self::readWord($handle), 'bitspersample' => self::readWord($handle), 'extraparamsize'=> 0, 'extraparams' => null ); if ($fmt['audioformat'] != 1) { //NON-PCM? $fmt['extraparamsize'] = self::readWord($handle); $fmt['extraparams'] = self::readString($handle, $fmt['extraparamsize']); } $data = array( 'id' => self::readString($handle, 4), 'size' => self::readLong($handle), 'data' => null ); //Do we need to read the data and, if so, does the specified size in subchunk2 match the actual size? $totalhdrssize = self::$HEADER_LENGTH + $fmt['extraparamsize']; if ($readdata && ($filesize - $totalhdrssize) == $data['size']) $data['data'] = fread($handle, $filesize - $totalhdrssize); //...aaaaand we're done! fclose($handle); //Do some checks... if (($fmt['numchannels'] * $fmt['samplerate'] * floor($fmt['bitspersample'] / 8)) != $fmt['byterate']) throw new Exception('Byterate field mismatch'); if (($fmt['numchannels'] * floor($fmt['bitspersample'] / 8)) != $fmt['blockalign']) throw new Exception('Blockalign field mismatch'); if ($riff['chunkid'] != 'RIFF') throw new Exception('RIFF chunk ID invalid'); if ($fmt['id'] != 'fmt ') throw new Exception('SubChunk1 chunk ID invalid'); if ($data['id'] != 'data') throw new Exception('SubChunk2 chunk ID invalid'); return array('header' => $riff, 'subchunk1' => $fmt, 'subchunk2' => $data); } //File is not readable or doesn't exist return false; @@ -81,10 +106,24 @@ public static function GetAudioFormat($audiofmtid) { switch($audiofmtid) { case 1: return 'PCM'; case 2: return 'Microsoft ADPCM'; case 6: return 'ITU G.711 a-law'; case 7: return 'ITU G.711 µ-law'; case 17: return 'IMA ADPCM'; case 20: return 'ITU G.723 ADPCM (Yamaha)'; case 49: return 'GSM 6.10'; case 64: return 'ITU G.721 ADPCM'; case 80: return 'MPEG'; case 65536: return 'Experimental'; default: return null; } -
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,140 @@ <?php /** * WaveFileReader; a simple class to read/parse WAVE file * (c)2012 Rob Janssen / https://github.com/RobThree * * Based on https://ccrma.stanford.edu/courses/422/projects/WaveFormat/ * * USAGE: * * $wav = WaveFileReader::ReadFile('/path/to/test.wav'); * var_dump($wav); * var_dump(WaveFileReader::GetAudioFormat($wav['subchunk1']['audioformat'])); */ class WaveFileReader { private static $HEADER_LENGTH = 44; //Header size is fixed /** * ReadFile reads the headers (and optionally the data) from a wave file * * @param string $filename The wave file to read the header from * @param bool $readdata (OPTIONAL) Pass TRUE to read the actual audio data from the file; defaults to FALSE * * @return mixed Information parsed from the file; FALSE when file doesn't exists or not readable */ public static function ReadFile($filename, $readdata = false) { //Make sure file is readable and exists if (is_readable($filename)) { $filesize = filesize($filename); //Make sure filesize is sane; e.g. at least the headers should be able to fit in it if ($filesize<self::$HEADER_LENGTH) return false; //Read the header and stuff all info in an array $handle = fopen($filename, 'rb'); $wav = array( 'header' => array( 'chunkid' => self::readString($handle, 4), 'chunksize' => self::readLong($handle), 'format' => self::readString($handle, 4) ), 'subchunk1' => array( 'id' => self::readString($handle, 4), 'size' => self::readLong($handle), 'audioformat' => self::readWord($handle), 'numchannels' => self::readWord($handle), 'samplerate' => self::readLong($handle), 'byterate' => self::readLong($handle), 'blockalign' => self::readWord($handle), 'bitspersample' => self::readWord($handle) ), 'subchunk2' => array( 'id' => self::readString($handle, 4), 'size' => self::readLong($handle), 'data' => null ) ); //Do we need to read the data and, if so, does the specified size in subchunk2 match the actual size? if ($readdata && ($filesize - self::$HEADER_LENGTH) == $wav['subchunk2']['size']) $wav['subchunk2']['data'] = fread($handle, $filesize - self::$HEADER_LENGTH); //...aaaaand we're done! fclose($handle); return $wav; } //File is not readable or doesn't exist return false; } /** * Returns a string representation of an audioformat "id" * * @param int $audiofmtid The audioformat "id" to get the string representation of * * @return string The audioformat as a string (e.g. "PCM", "ALAW", "ULAW", ...), NULL when an * unknown audioformat "id" is passed */ public static function GetAudioFormat($audiofmtid) { switch($audiofmtid) { case 1: return 'PCM'; case 6: return 'ALAW'; case 7: return 'ULAW'; default: return null; } } /** * Reads a string from the specified file handle * * @param int $handle The filehandle to read the string from * @param int $length The number of bytes to read * * @return string The string read from the file */ private static function readString($handle, $length) { return self::readUnpacked($handle, 'a*', $length); } /** * Reads a 32bit unsigned integer from the specified file handle * * @param int $handle The filehandle to read the 32bit unsigned integer from * * @return int The 32bit unsigned integer read from the file */ private static function readLong($handle) { return self::readUnpacked($handle, 'V', 4); } /** * Reads a 16bit unsigned integer from the specified file handle * * @param int $handle The filehandle to read the 16bit unsigned integer from * * @return int The 16bit unsigned integer read from the file */ private static function readWord($handle) { return self::readUnpacked($handle, 'v', 2); } /** * Reads the specified number of bytes from a specified file handle and unpacks it accoring to the specified type * * @param int $handle The filehandle to read the data from * @param int $type The type of data being read (see PHP's Pack() documentation) * @param int $length The number of bytes to read * * @return mixed The unpacked data read from the file */ private static function readUnpacked($handle, $type, $length) { $r = unpack($type, fread($handle, $length)); return array_pop($r); } }