php获取flv视频时间方法

php获取flv时间!有源码！拿来就可以使用！超级简单。 

<?php
function BigEndian2Int($byte_word, $signed = false) {
$int_value = 0;

$byte_wordlen = strlen($byte_word);

for ($i = 0; $i < $byte_wordlen; $i++)
{

$int_value += ord($byte_word{$i}) * pow(256, ($byte_wordlen - 1 - $i));

}
if ($signed)
{

$sign_mask_bit = 0x80 << (8 * ($byte_wordlen - 1));

if ($int_value & $sign_mask_bit)
{

$int_value = 0 - ($int_value & ($sign_mask_bit - 1));

}

}

return $int_value;

}

function getTime($name){

if(!file_exists($name)){

return;

}

$flv_data_length=filesize($name);

$fp = @fopen($name, 'rb');

$flv_header = fread($fp, 5);

fseek($fp, 5, SEEK_SET);

$frame_size_data_length =BigEndian2Int(fread($fp, 4));

$flv_header_frame_length = 9;

if ($frame_size_data_length > $flv_header_frame_length) {

fseek($fp, $frame_size_data_length - $flv_header_frame_length, SEEK_CUR);

}

$duration = 0;

while ((ftell($fp) + 1) < $flv_data_length) {

$this_tag_header = fread($fp, 16);

$data_length = BigEndian2Int(substr($this_tag_header, 5, 3));

$timestamp = BigEndian2Int(substr($this_tag_header, 8, 3));

$next_offset = ftell($fp) - 1 + $data_length;

if ($timestamp > $duration) {

$duration = $timestamp;

}

fseek($fp, $next_offset, SEEK_SET);

}

fclose($fp);

return $duration;

}

function fn($time){

$num = $time;

$sec = intval($num / 1000);

$h = intval($sec / 3600);

$m = intval(($sec % 3600) / 60);

$s = intval(($sec % 60 ));

$tm = $h . ':' . $m . ':' . $s ;

return $tm;

}

echo getTime("27729.flv");//显示数字时间如236722

echo fn(236722); //显示时间格式0:03:56

?>