获取音频文件的长度 php
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Get the length of an audio file php
提问by Belgin Fish
How I can get the length of an audio file in php.
如何在 php.ini 中获取音频文件的长度。
If it's too hard to do in php then any other way should work alright.
如果在 php 中很难做到，那么任何其他方式都可以正常工作。
采纳答案by Radek Suski
What kind of audio file? mp3? wav? Anyway you will probably need some specific library. See: http://de.php.net/manual/en/refs.utilspec.audio.php
什么样的音频文件？mp3？哇？无论如何，您可能需要一些特定的库。请参阅：http: //de.php.net/manual/en/refs.utilspec.audio.php
回答by Stephen Fuhry
If you're using linux / unix and have ffmpeg installed, just do this:
如果您使用的是 linux / unix 并安装了 ffmpeg，请执行以下操作：
$time = exec("ffmpeg -i " . escapeshellarg($path) . " 2>&1 | grep 'Duration' | cut -d ' ' -f 4 | sed s/,//");
list($hms, $milli) = explode('.', $time);
list($hours, $minutes, $seconds) = explode(':', $hms);
$total_seconds = ($hours * 3600) + ($minutes * 60) + $seconds;
回答by Tobias P.
PHP has no standard audio support, you'll have to recompile PHP yourself, or you can use a tool to get the information:
PHP 没有标准的音频支持，您必须自己重新编译 PHP，或者您可以使用工具来获取信息：
You could use ffmpeg. Running ffmpeg as follows:
你可以使用 ffmpeg。运行ffmpeg如下：
ffmpeg -i someAudio.mp3
will produce this output:
将产生这个输出：
Input #0, mp3, from 'someAudio.mp3':
Duration: 00:00:34.03, start: 0.000000, bitrate: 127 kb/s
Stream #0.0: Audio: mp3, 48000 Hz, mono, s16, 128 kb/s
now you'll only need a regexp to parse the result.
现在你只需要一个正则表达式来解析结果。
回答by Licson
If you're dealing with wave files, you just need to divide the wave sample length with the sample rate and you can get the length of the audio in seconds.
如果您正在处理波形文件，则只需将波形样本长度除以采样率即可获得音频的长度（以秒为单位）。
回答by Dariusz Majchrzak
If you/somebody want to measure mp3 duration, I found some piece of code, works nice and no extensions are needed
如果您/某人想测量 mp3 持续时间，我找到了一些代码，效果很好，不需要扩展
http://www.zedwood.com/article/php-calculate-duration-of-mp3
http://www.zedwood.com/article/php-calculate-duration-of-mp3
ctrl+v
Ctrl+V
<?php
$mp3file = new MP3File("npr_304314290.mp3");//http://www.npr.org/rss/podcast.php?id=510282
$duration1 = $mp3file->getDurationEstimate();//(faster) for CBR only
$duration2 = $mp3file->getDuration();//(slower) for VBR (or CBR)
echo "duration: $duration1 seconds"."\n";
echo "estimate: $duration2 seconds"."\n";
echo MP3File::formatTime($duration2)."\n";
?>
class:
班级：
<?php
class MP3File
{
protected $filename;
public function __construct($filename)
{
$this->filename = $filename;
}
public static function formatTime($duration) //as hh:mm:ss
{
//return sprintf("%d:%02d", $duration/60, $duration%60);
$hours = floor($duration / 3600);
$minutes = floor( ($duration - ($hours * 3600)) / 60);
$seconds = $duration - ($hours * 3600) - ($minutes * 60);
return sprintf("%02d:%02d:%02d", $hours, $minutes, $seconds);
}
//Read first mp3 frame only... use for CBR constant bit rate MP3s
public function getDurationEstimate()
{
return $this->getDuration($use_cbr_estimate=true);
}
//Read entire file, frame by frame... ie: Variable Bit Rate (VBR)
public function getDuration($use_cbr_estimate=false)
{
$fd = fopen($this->filename, "rb");
$duration=0;
$block = fread($fd, 100);
$offset = $this->skipID3v2Tag($block);
fseek($fd, $offset, SEEK_SET);
while (!feof($fd))
{
$block = fread($fd, 10);
if (strlen($block)<10) { break; }
//looking for 1111 1111 111 (frame synchronization bits)
else if ($block[0]=="\xff" && (ord($block[1])&0xe0) )
{
$info = self::parseFrameHeader(substr($block, 0, 4));
if (empty($info['Framesize'])) { return $duration; } //some corrupt mp3 files
fseek($fd, $info['Framesize']-10, SEEK_CUR);
$duration += ( $info['Samples'] / $info['Sampling Rate'] );
}
else if (substr($block, 0, 3)=='TAG')
{
fseek($fd, 128-10, SEEK_CUR);//skip over id3v1 tag size
}
else
{
fseek($fd, -9, SEEK_CUR);
}
if ($use_cbr_estimate && !empty($info))
{
return $this->estimateDuration($info['Bitrate'],$offset);
}
}
return round($duration);
}
private function estimateDuration($bitrate,$offset)
{
$kbps = ($bitrate*1000)/8;
$datasize = filesize($this->filename) - $offset;
return round($datasize / $kbps);
}
private function skipID3v2Tag(&$block)
{
if (substr($block, 0,3)=="ID3")
{
$id3v2_major_version = ord($block[3]);
$id3v2_minor_version = ord($block[4]);
$id3v2_flags = ord($block[5]);
$flag_unsynchronisation = $id3v2_flags & 0x80 ? 1 : 0;
$flag_extended_header = $id3v2_flags & 0x40 ? 1 : 0;
$flag_experimental_ind = $id3v2_flags & 0x20 ? 1 : 0;
$flag_footer_present = $id3v2_flags & 0x10 ? 1 : 0;
$z0 = ord($block[6]);
$z1 = ord($block[7]);
$z2 = ord($block[8]);
$z3 = ord($block[9]);
if ( (($z0&0x80)==0) && (($z1&0x80)==0) && (($z2&0x80)==0) && (($z3&0x80)==0) )
{
$header_size = 10;
$tag_size = (($z0&0x7f) * 2097152) + (($z1&0x7f) * 16384) + (($z2&0x7f) * 128) + ($z3&0x7f);
$footer_size = $flag_footer_present ? 10 : 0;
return $header_size + $tag_size + $footer_size;//bytes to skip
}
}
return 0;
}
public static function parseFrameHeader($fourbytes)
{
static $versions = array(
0x0=>'2.5',0x1=>'x',0x2=>'2',0x3=>'1', // x=>'reserved'
);
static $layers = array(
0x0=>'x',0x1=>'3',0x2=>'2',0x3=>'1', // x=>'reserved'
);
static $bitrates = array(
'V1L1'=>array(0,32,64,96,128,160,192,224,256,288,320,352,384,416,448),
'V1L2'=>array(0,32,48,56, 64, 80, 96,112,128,160,192,224,256,320,384),
'V1L3'=>array(0,32,40,48, 56, 64, 80, 96,112,128,160,192,224,256,320),
'V2L1'=>array(0,32,48,56, 64, 80, 96,112,128,144,160,176,192,224,256),
'V2L2'=>array(0, 8,16,24, 32, 40, 48, 56, 64, 80, 96,112,128,144,160),
'V2L3'=>array(0, 8,16,24, 32, 40, 48, 56, 64, 80, 96,112,128,144,160),
);
static $sample_rates = array(
'1' => array(44100,48000,32000),
'2' => array(22050,24000,16000),
'2.5' => array(11025,12000, 8000),
);
static $samples = array(
1 => array( 1 => 384, 2 =>1152, 3 =>1152, ), //MPEGv1, Layers 1,2,3
2 => array( 1 => 384, 2 =>1152, 3 => 576, ), //MPEGv2/2.5, Layers 1,2,3
);
//$b0=ord($fourbytes[0]);//will always be 0xff
$b1=ord($fourbytes[1]);
$b2=ord($fourbytes[2]);
$b3=ord($fourbytes[3]);
$version_bits = ($b1 & 0x18) >> 3;
$version = $versions[$version_bits];
$simple_version = ($version=='2.5' ? 2 : $version);
$layer_bits = ($b1 & 0x06) >> 1;
$layer = $layers[$layer_bits];
$protection_bit = ($b1 & 0x01);
$bitrate_key = sprintf('V%dL%d', $simple_version , $layer);
$bitrate_idx = ($b2 & 0xf0) >> 4;
$bitrate = isset($bitrates[$bitrate_key][$bitrate_idx]) ? $bitrates[$bitrate_key][$bitrate_idx] : 0;
$sample_rate_idx = ($b2 & 0x0c) >> 2;//0xc => b1100
$sample_rate = isset($sample_rates[$version][$sample_rate_idx]) ? $sample_rates[$version][$sample_rate_idx] : 0;
$padding_bit = ($b2 & 0x02) >> 1;
$private_bit = ($b2 & 0x01);
$channel_mode_bits = ($b3 & 0xc0) >> 6;
$mode_extension_bits = ($b3 & 0x30) >> 4;
$copyright_bit = ($b3 & 0x08) >> 3;
$original_bit = ($b3 & 0x04) >> 2;
$emphasis = ($b3 & 0x03);
$info = array();
$info['Version'] = $version;//MPEGVersion
$info['Layer'] = $layer;
//$info['Protection Bit'] = $protection_bit; //0=> protected by 2 byte CRC, 1=>not protected
$info['Bitrate'] = $bitrate;
$info['Sampling Rate'] = $sample_rate;
//$info['Padding Bit'] = $padding_bit;
//$info['Private Bit'] = $private_bit;
//$info['Channel Mode'] = $channel_mode_bits;
//$info['Mode Extension'] = $mode_extension_bits;
//$info['Copyright'] = $copyright_bit;
//$info['Original'] = $original_bit;
//$info['Emphasis'] = $emphasis;
$info['Framesize'] = self::framesize($layer, $bitrate, $sample_rate, $padding_bit);
$info['Samples'] = $samples[$simple_version][$layer];
return $info;
}
private static function framesize($layer, $bitrate,$sample_rate,$padding_bit)
{
if ($layer==1)
return intval(((12 * $bitrate*1000 /$sample_rate) + $padding_bit) * 4);
else //layer 2, 3
return intval(((144 * $bitrate*1000)/$sample_rate) + $padding_bit);
}
}
回答by Ryan
An improvement of Stephen Fuhry's answer:
斯蒂芬富里的答案的改进：
/**
* https://stackoverflow.com/a/7135484/470749
* @param string $path
* @return int
*/
function getDurationOfWavInMs($path) {
$time = getDurationOfWav($path);
list($hms, $milli) = explode('.', $time);
list($hours, $minutes, $seconds) = explode(':', $hms);
$totalSeconds = ($hours * 3600) + ($minutes * 60) + $seconds;
return ($totalSeconds * 1000) + $milli;
}
/**
*
* @param string $path
* @return string
*/
function getDurationOfWav($path) {
$cmd = "ffmpeg -i " . escapeshellarg($path) . " 2>&1 | grep 'Duration' | cut -d ' ' -f 4 | sed s/,//";
return exec($cmd);
}
Thanks, Stephen! This is working well for me (although it is slow for hundreds of files).
谢谢，斯蒂芬！这对我来说效果很好（尽管数百个文件很慢）。
