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。