PHP实现获取FLV文件的时间

PHP如何获取FLV文件时间呢,答案是fopen文件后查看FLV文件是HEX数据,并转换为number。

<?php

functionBigEndian2Int($byte_word,$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;

}

 

functiongetTime($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;

}

 

functionget_flv_file_time($time)

{

$time=getTime($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;

}

 

?>

直接使用get_flv_file_time(“你的FLV.flv”)即可。