contrib/audio.php

   1 <?php
   2 $GLOBALS['options'] = [
   3         'analyze_input' => FALSE,
   4         'reduce_noise'  => FALSE,
   5         'ignore_noise'  => FALSE,
   6         'keep_noise'    => FALSE,
   7         'buffer_size'   => 8,
   8 ];
   9
  10 if (isset($_SERVER['argv'][1]) && $_SERVER['argv'][1] == 'a') {
  11         $GLOBALS['options']['analyze_input'] = TRUE;
  12 } elseif (isset($_SERVER['argv'][1]) && $_SERVER['argv'][1] == 'r') {
  13         $GLOBALS['options']['reduce_noise'] = TRUE;
  14 } elseif (isset($_SERVER['argv'][1]) && $_SERVER['argv'][1] == 'k') {
  15         $GLOBALS['options']['keep_noise'] = TRUE;
  16 }
  17
  18 if (isset($_SERVER['argv'][1]) && $_SERVER['argv'][1] == 'i') {
  19         $GLOBALS['options']['ignore_noise'] = TRUE;
  20 } elseif (isset($_SERVER['argv'][2]) && $_SERVER['argv'][2] == 'i') {
  21         $GLOBALS['options']['ignore_noise'] = TRUE;
  22 } elseif (isset($_SERVER['argv'][2]) && $_SERVER['argv'][2] == 'k') {
  23         $GLOBALS['options']['keep_noise'] = TRUE;
  24 }
  25
  26 function analyzeForNoiseOnly ($data) {
  27         $GLOBALS['analysis']['breakdown'] = [];
  28         $GLOBALS['analysis']['average']   = 0;
  29
  30         for ($i = 0; $i < strlen($data); $i++) {
  31                 $ord = ord(substr($data, $i, 1));
  32                 $GLOBALS['analysis']['breakdown'][$ord] = TRUE;
  33                 $GLOBALS['analysis']['average'] += $ord;
  34         }
  35
  36         if (!$GLOBALS['options']['keep_noise'] && !$GLOBALS['options']['ignore_noise'] && count($GLOBALS['analysis']['breakdown']) == 2 && isset($GLOBALS['analysis']['breakdown'][127]) && isset($GLOBALS['analysis']['breakdown'][128])) {
  37                 if ($GLOBALS['options']['analyze_input']) {
  38                         //echo 'NOISE1!' . PHP_EOL;
  39                 }
  40                 return NULL;
  41         } elseif (!$GLOBALS['options']['keep_noise'] && !$GLOBALS['options']['ignore_noise'] && count($GLOBALS['analysis']['breakdown']) == 1 && isset($GLOBALS['analysis']['breakdown'][127])) {
  42                 if ($GLOBALS['options']['analyze_input']) {
  43                         //echo 'NOISE2!' . PHP_EOL;
  44                 }
  45                 return NULL;
  46         } elseif (!$GLOBALS['options']['keep_noise'] && $GLOBALS['options']['ignore_noise'] && count($GLOBALS['analysis']['breakdown']) < 2) {
  47                 if ($GLOBALS['options']['analyze_input']) {
  48                         //echo 'NOISE3!' . PHP_EOL;
  49                 }
  50                 return NULL;
  51         }
  52
  53         // Return given data
  54         return $data;
  55 }
  56
  57 //$pcm = fopen('output1.pcm', 'rb') or die('Cannot read from audio');
  58 $pcm = fopen('/dev/dsp', 'rb') or die('Cannot read from audio' . PHP_EOL);
  59
  60 $empty = str_repeat(chr(128), $GLOBALS['options']['buffer_size']);
  61
  62 while (TRUE) {
  63         //usleep(100);
  64         $data = trim(fread($pcm, $GLOBALS['options']['buffer_size']));
  65         if ((empty($data)) || ($data == $empty)) {
  66                 if ($GLOBALS['options']['analyze_input']) {
  67                         //echo 'EMPTY!' . PHP_EOL;
  68                 }
  69                 continue;
  70         }
  71
  72         // Detect noise
  73         $data = analyzeForNoiseOnly($data);
  74
  75         // Empty?
  76         if (empty($data)) {
  77                 // Skip this
  78                 continue;
  79         } // END - if
  80
  81         $GLOBALS['analysis']['average'] = floor($GLOBALS['analysis']['average'] / strlen($data));
  82
  83         if ($GLOBALS['options']['analyze_input']) {
  84                 $simpleAnalysis = '';
  85                 for ($i = 0; $i < strlen($data); $i++) {
  86                         $ord = ord(substr($data, $i, 1));
  87                         $simpleAnalysis .= str_pad($ord, 3, '0', STR_PAD_LEFT) . '=0x' . str_pad(dechex($ord), 2, '0', STR_PAD_LEFT) . ',';
  88                 }
  89                 $simpleAnalysis = substr($simpleAnalysis, 0, -1) . ' (' . count($GLOBALS['analysis']['breakdown']) . ')' . PHP_EOL;
  90
  91                 echo $simpleAnalysis;
  92         } elseif ($GLOBALS['options']['reduce_noise']) {
  93                 $out = '';
  94                 for ($i = 0; $i < strlen($data); $i++) {
  95                         $ord = ord(substr($data, $i, 1));
  96                         // @TODO What do here to remove noise?
  97                         $ord -= $GLOBALS['analysis']['average'];
  98                         $out .= chr($ord);
  99                 }
 100
 101                 $out = analyzeForNoiseOnly($out);
 102
 103                 if (empty($out)) {
 104                         // Skip this
 105                         continue;
 106                 } // END - if
 107
 108                 echo $out;
 109         } else {
 110                 echo $data;
 111         }
 112
 113         if (feof($pcm)) {
 114                 if ($GLOBALS['options']['analyze_input']) {
 115                         echo 'EOF!' . PHP_EOL;
 116                 }
 117                 break;
 118         }
 119 }
 120
 121 fclose($pcm);