php - 用php生成mp3波形

Question

我需要构建一个将 mp3 文件转换为波形图像的 Web 脚本，并且我 came across this website .

我已经将 PHP 文件以及 .dll 和 .exe 文件从 LAMB 上传到我的网站(由 host monster 托管)。

但是当我尝试在网站上上传 MP3 文件时，它只会生成黑色图像而不是波形图像。

我对 PHP 了解不多，所以我不太清楚哪里出了问题，但我猜它与程序的上传部分有关。

谁能告诉我哪里出了问题，我该如何克服它？

以下是原样的 php 代码(也可用 in this repository on GitHub )。

  <?php

  ini_set("max_execution_time", "30000");

  // how much detail we want. Larger number means less detail
  // (basically, how many bytes/frames to skip processing)
  // the lower the number means longer processing time
  define("DETAIL", 5);

  define("DEFAULT_WIDTH", 500);
  define("DEFAULT_HEIGHT", 100);
  define("DEFAULT_FOREGROUND", "#FF0000");
  define("DEFAULT_BACKGROUND", "#FFFFFF");

  /**
   * GENERAL FUNCTIONS
   */
  function findValues($byte1, $byte2){
    $byte1 = hexdec(bin2hex($byte1));                        
    $byte2 = hexdec(bin2hex($byte2));                        
    return ($byte1 + ($byte2*256));
  }

  /**
   * Great function slightly modified as posted by Minux at
   * http://forums.clantemplates.com/showthread.php?t=133805
   */
  function html2rgb($input) {
    $input=($input[0]=="#")?substr($input, 1,6):substr($input, 0,6);
    return array(
     hexdec(substr($input, 0, 2)),
     hexdec(substr($input, 2, 2)),
     hexdec(substr($input, 4, 2))
    );
  }   

  if (isset($_FILES["mp3"])) {

/**
 * PROCESS THE FILE
 */

// temporary file name
$tmpname = substr(md5(time()), 0, 10);

// copy from temp upload directory to current
copy($_FILES["mp3"]["tmp_name"], "{$tmpname}_o.mp3");

    // support for stereo waveform?
$stereo = isset($_POST["stereo"]) && $_POST["stereo"] == "on" ? true : false;

    // array of wavs that need to be processed
$wavs_to_process = array();

/**
 * convert mp3 to wav using lame decoder
 * First, resample the original mp3 using as mono (-m m), 16 bit (-b 16), and 8 KHz (--resample 8)
 * Secondly, convert that resampled mp3 into a wav
 * We don't necessarily need high quality audio to produce a waveform, doing this process reduces the WAV
 * to it's simplest form and makes processing significantly faster
 */
if ($stereo) {
        // scale right channel down (a scale of 0 does not work)
  exec("lame {$tmpname}_o.mp3 --scale-r 0.1 -m m -S -f -b 16 --resample 8 {$tmpname}.mp3 && lame -S --decode {$tmpname}.mp3 {$tmpname}_l.wav");
        // same as above, left channel
  exec("lame {$tmpname}_o.mp3 --scale-l 0.1 -m m -S -f -b 16 --resample 8 {$tmpname}.mp3 && lame -S --decode {$tmpname}.mp3 {$tmpname}_r.wav");
  $wavs_to_process[] = "{$tmpname}_l.wav";
  $wavs_to_process[] = "{$tmpname}_r.wav";
} else {
  exec("lame {$tmpname}_o.mp3 -m m -S -f -b 16 --resample 8 {$tmpname}.mp3 && lame -S --decode {$tmpname}.mp3 {$tmpname}.wav");
  $wavs_to_process[] = "{$tmpname}.wav";
}

// delete temporary files
unlink("{$tmpname}_o.mp3");
unlink("{$tmpname}.mp3");

// get user vars from form
$width = isset($_POST["width"]) ? (int) $_POST["width"] : DEFAULT_WIDTH;
$height = isset($_POST["height"]) ? (int) $_POST["height"] : DEFAULT_HEIGHT;
$foreground = isset($_POST["foreground"]) ? $_POST["foreground"] : DEFAULT_FOREGROUND;
$background = isset($_POST["background"]) ? $_POST["background"] : DEFAULT_BACKGROUND;
$draw_flat = isset($_POST["flat"]) && $_POST["flat"] == "on" ? true : false;

$img = false;

// generate foreground color
list($r, $g, $b) = html2rgb($foreground);

// process each wav individually
for($wav = 1; $wav <= sizeof($wavs_to_process); $wav++) {

  $filename = $wavs_to_process[$wav - 1];

  /**
   * Below as posted by "zvoneM" on
   * http://forums.devshed.com/php-development-5/reading-16-bit-wav-file-318740.html
   * as findValues() defined above
   * Translated from Croation to English - July 11, 2011
   */
  $handle = fopen($filename, "r");
  // wav file header retrieval
  $heading[] = fread($handle, 4);
  $heading[] = bin2hex(fread($handle, 4));
  $heading[] = fread($handle, 4);
  $heading[] = fread($handle, 4);
  $heading[] = bin2hex(fread($handle, 4));
  $heading[] = bin2hex(fread($handle, 2));
  $heading[] = bin2hex(fread($handle, 2));
  $heading[] = bin2hex(fread($handle, 4));
  $heading[] = bin2hex(fread($handle, 4));
  $heading[] = bin2hex(fread($handle, 2));
  $heading[] = bin2hex(fread($handle, 2));
  $heading[] = fread($handle, 4);
  $heading[] = bin2hex(fread($handle, 4));

  // wav bitrate 
  $peek = hexdec(substr($heading[10], 0, 2));
  $byte = $peek / 8;

  // checking whether a mono or stereo wav
  $channel = hexdec(substr($heading[6], 0, 2));

  $ratio = ($channel == 2 ? 40 : 80);

  // start putting together the initial canvas
  // $data_size = (size_of_file - header_bytes_read) / skipped_bytes + 1
  $data_size = floor((filesize($filename) - 44) / ($ratio + $byte) + 1);
  $data_point = 0;

  // now that we have the data_size for a single channel (they both will be the same)
  // we can initialize our image canvas
  if (!$img) {
    // create original image width based on amount of detail
            // each waveform to be processed with be $height high, but will be condensed
            // and resized later (if specified)
    $img = imagecreatetruecolor($data_size / DETAIL, $height * sizeof($wavs_to_process));

    // fill background of image
    if ($background == "") {
      // transparent background specified
      imagesavealpha($img, true);
      $transparentColor = imagecolorallocatealpha($img, 0, 0, 0, 127);
      imagefill($img, 0, 0, $transparentColor);
    } else {
      list($br, $bg, $bb) = html2rgb($background);
      imagefilledrectangle($img, 0, 0, (int) ($data_size / DETAIL), $height * sizeof($wavs_to_process), imagecolorallocate($img, $br, $bg, $bb));
    }
  }

  while(!feof($handle) && $data_point < $data_size){
    if ($data_point++ % DETAIL == 0) {
      $bytes = array();

      // get number of bytes depending on bitrate
      for ($i = 0; $i < $byte; $i++)
        $bytes[$i] = fgetc($handle);

      switch($byte){
        // get value for 8-bit wav
        case 1:
          $data = findValues($bytes[0], $bytes[1]);
          break;
        // get value for 16-bit wav
        case 2:
          if(ord($bytes[1]) & 128)
            $temp = 0;
          else
            $temp = 128;
          $temp = chr((ord($bytes[1]) & 127) + $temp);
          $data = floor(findValues($bytes[0], $temp) / 256);
          break;
      }

      // skip bytes for memory optimization
      fseek($handle, $ratio, SEEK_CUR);

      // draw this data point
      // relative value based on height of image being generated
      // data values can range between 0 and 255
      $v = (int) ($data / 255 * $height);

      // don't print flat values on the canvas if not necessary
      if (!($v / $height == 0.5 && !$draw_flat))
        // draw the line on the image using the $v value and centering it vertically on the canvas
        imageline(
          $img,
          // x1
          (int) ($data_point / DETAIL),
          // y1: height of the image minus $v as a percentage of the height for the wave amplitude
          $height * $wav - $v,
          // x2
          (int) ($data_point / DETAIL),
          // y2: same as y1, but from the bottom of the image
          $height * $wav - ($height - $v),
          imagecolorallocate($img, $r, $g, $b)
        );         

    } else {
      // skip this one due to lack of detail
      fseek($handle, $ratio + $byte, SEEK_CUR);
    }
  }

  // close and cleanup
  fclose($handle);

  // delete the processed wav file
  unlink($filename);

}

header("Content-Type: image/png");

// want it resized?
if ($width) {
  // resample the image to the proportions defined in the form
  $rimg = imagecreatetruecolor($width, $height);
  // save alpha from original image
  imagesavealpha($rimg, true);
  imagealphablending($rimg, false);
  // copy to resized
  imagecopyresampled($rimg, $img, 0, 0, 0, 0, $width, $height, imagesx($img), imagesy($img));
  imagepng($rimg);
  imagedestroy($rimg);
} else {
  imagepng($img);
}

imagedestroy($img);

  } else {

?>

  <form method="post" action="<?php print $_SERVER["REQUEST_URI"]; ?>"     enctype="multipart/form-data">

  <p>MP3 File:<br />
    <input type="file" name="mp3" /></p>

  <p>Image Width:<br />
    <input type="text" name="width" value="<?php print DEFAULT_WIDTH; ?>" /></p>

  <p>Image Height:<br />
    <input type="text" name="height" value="<?php print DEFAULT_HEIGHT; ?>" /></p>

  <p>Foreground Color: <small>(HEX/HTML color code)</small><br />
    <input type="text" name="foreground" value="<?php print DEFAULT_FOREGROUND; ?>" /></p>

  <p>Background Color: (Leave blank for transparent background) <small>(HEX/HTML color code)</small><br />
    <input type="text" name="background" value="<?php print DEFAULT_BACKGROUND; ?>" /></p>

  <p>Draw flat-line? <input type="checkbox" name="flat" /></p>

  <p>Stereo waveform? <input type="checkbox" name="stereo" /></p>

  <p><input type="submit" value="Generate Waveform" /></p>

  </form>

<?php

  }    

Answer 1

在这里看看这个，它只是一个 PHP 实现的你正在尝试做的事情:http://www.phpclasses.org/package/482-PHP-Extracts-attributes-of-audio-files-Visualization.html