Add wave playback example

Author: santiagolizardo

examples/WaveFileReader.php

@@ -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);
+ }
+}

examples/example.php

@@ -0,0 +1,30 @@
+<?php declare(strict_types=1);
+
+dl('openal.so');
+
+require 'WaveFileReader.php';
+
+// https://freesound.org/people/Ironi%20Alef/sounds/32226/
+$wave = WaveFileReader::ReadFile('sound.wav', true);
+$waveData = $wave['subchunk2']['data'];
+$waveSampleRate = $wave['subchunk1']['samplerate'];
+$waveLength = ceil(strlen($waveData) / ($waveSampleRate * $wave['subchunk1']['numchannels'] * $wave['subchunk1']['bitspersample'] /8));
+
+$device = openal_device_open();
+$context = openal_context_create($device);
+openal_context_current($context);
+
+$source = openal_source_create();
+$buffer = openal_buffer_create();
+openal_buffer_data($buffer, AL_FORMAT_STEREO16, $waveData, $waveSampleRate);
+
+openal_source_set($source, AL_BUFFER, $buffer);
+openal_source_set($source, AL_LOOPING, true);
+
+openal_source_play($source);
+sleep((int)$waveLength);
+openal_source_stop($source);
+
+openal_context_destroy($context);
+openal_device_close($device);
+