SWFMovie::streamMP3

(PHP 5 < 5.3.0, PECL ming SVN)

SWFMovie::streamMP3 — Streams a MP3 file

说明

SWFMovie::streamMP3 ( mixed $mp3file [, float $skip = 0 ] ) : int
Warning

此函数是实验性的。此函数的表象，包括名称及其相关文档都可能在未来的 PHP 发布版本中未通知就被修改。使用本函数风险自担 。

Streams the given MP3 file mp3file.

This method is not very robust in dealing with oddities (can skip over an initial ID3 tag, but that's about it).

Note that the movie isn't smart enough to put enough frames in to contain the entire mp3 stream- you'll have to add (length of song * frames per second) frames to get the entire stream in.

参数

mp3file

Can be a file pointer returned by fopen() or the MP3 data, as a binary string.

skip

Number of seconds to skip.

返回值

Return number of frames.

更新日志

版本 说明
5.2.0 skip added

范例

Example #1 Streaming example

<?php
$m = new SWFMovie();
$m->setRate(12.0);
$m->streamMp3(file_get_contents("distortobass.mp3"));
// use your own MP3

// The file is 11.85 seconds at 12.0 fps = 142 frames
$m->setFrames(142);

header('Content-type: application/x-shockwave-flash');
$m->output();
?>

User Contributed Notes

aaronmason85 at gmail dot com 18-May-2009 09:44
Hey all,

For those using Ming 0.3 (like me), there is a way to calculate the length of the MP3 you are using.  It might be a bit iffy for VBR files, but it seems to work well for the files I've tested thus far.  The process of calculating the frame length (and size) is detailed at http://www.mpgedit.org/mpgedit/mpeg_format/mpeghdr.htm

<?php

function get_mp3_len ($file) {

        $rate1=array(0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, "bad");
        $rate2=array(0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, "bad");
        $rate3=array(0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, "bad");
        $rate4=array(0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, "bad");
        $rate5=array(0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, "bad");

        $bitrate=array(
                '1'  => $rate5,
                '2'  => $rate5,
                '3'  => $rate4,
                '9'  => $rate5,
                '10' => $rate5,
                '11' => $rate4,
                '13' => $rate3,
                '14' => $rate2,
                '15' => $rate1
        );

        $sample=array(
                '0'  => 11025,
                '1'  => 12000,
                '2'  => 8000,
                '8'  => 22050,
                '9'  => 24000,
                '10' => 16000,
                '12' => 44100,
                '13' => 48000,
                '14' => 32000
        );

        $fd=fopen($file, 'rb');
        $header=fgets($fd, 5);
        fclose($fd);

        $bits="";
        while (strlen($header) > 0) {

                //var_dump($header);
                $bits.=str_pad(base_convert(ord($header{0}), 10, 2), 8, '0', STR_PAD_LEFT);
                $header=substr($header, 1);
        }

        $bits=substr($bits, 11); // lets strip the frame sync bits first.

        $version=substr($bits, 0, 2); // this gives us the version
        $layer=base_convert(substr($bits, 2, 2), 2, 10); // this gives us the layer
        $verlay=base_convert(substr($bits, 0, 4), 2, 10); // this gives us both

        $rateidx=base_convert(substr($bits, 5, 4), 2, 10); // this gives us the bitrate index
        $sampidx=base_convert($version.substr($bits, 9, 2), 2, 10); // this gives the sample index
        $padding=substr($bits, 11, 1); // are we padding frames?

        $rate=$bitrate[$verlay][$rateidx];
        $samp=$sample[$sampidx];

        $framelen=0;
        $framesize=384; // Size of the frame in samples
        if ($layer == 3) { // layer 1?
                $framelen=(12 * ($rate * 1000) / $samp + $padding) * 4;
        } else { // Layer 2 and 3
                $framelen=144 * ($rate * 1000) / $samp + $padding;
                $framesize=1152;
        }

        $headerlen=4 + ($bits{4} == 0 ? '2' : '0');

        return (filesize($file) - $headerlen) / $framelen / ($samp / $framesize);
}

?>
Richard Trigaux 25-Feb-2009 09:30
Seems that this function only handles some MP3 files with specified sample rates and not others. 44100 and 21050 work. With the lame MP3 converter, this is obtained with setting the "bit rate" at 112 (average compression/quality), mono or stereo. Other values may work, probably multiples, I did not tried all.
diana 07-Mar-2008 03:05
If you need to play an mp3 fully you need to do something like:

<?php
$len = $m->streamMp3(fopen("sound.mp3", "r"));
$m->setFrames($len);
?>

This works only in Ming 0.4. I'm not 100% sure but it doesn't sound to work on Ming 0.3
boreckiwebs at gmail dot com 24-Aug-2006 09:54
if you want to control the sound use these functions like this:

<?php

$m -> add(new SWFAction('
 stop(); // pauses the song
 goToAndStop(1); // stops the song, and goes back to the beginning
 play(); // plays the song from current position
'));

?>

i hope this is helpful
boo at php dot net 20-Sep-2002 03:02
Don't forget to use fopen function in example above !

Use

<?php
$m->streamMp3(fopen("distortobass.mp3", "rb"));
instead of
$m->streamMp3("distortobass.mp3");
?>

I hope this is useful for you :)
mued at muetdhiver dot org 17-May-2001 09:39
a nice feature to handle Id3tag is to get support from Unix mp3info command into a returning exec parsing