本文实例讲述了PHP从FLV文件获取视频预览图的方法。分享给大家供大家参考。具体实现方法如下：

复制代码 代码如下:<?php

// references http://www.longtailvideo.com/support/forum/Modules/12661/External-PHP-with-FFmpeg-using-readfile-

// generate a preview image from an FLV file on-the-fly, or to save

// call with: ffmpeg_image.php?file=video.flv&time=00:00:05&browser=true

// call with: ffmpeg_image.php?file=video.flv&percent=75.3&browser=true

// no time defaults to "00:00:01" (one second), no browser defaults to "true"

$videofile = (isset($_GET['file'])) ? strval($_GET['file']) : 'video.flv';

$image = substr($videofile, 0, strlen($videofile) - 4);

$time = (isset($_GET['time'])) ? strval($_GET['time']) : '00:00:01';

// debug (" File: ", $videofile);

// debug (" Image: ", $image);

// debug (" Time: ", $time);

// check time format

if (!preg_match('/dd:dd:dd/', $time))

{

$time = "00:00:00";

}

if (isset($_GET['percent']))

{

$percent = $_GET['percent'];

// debug (" Percent: ", $percent);

ob_start();

exec("/usr/bin/ffmpeg -i "". $videofile . "" 2>&1");

$duration = ob_get_contents();

ob_end_clean();

// debug ("Duration: ", $duration);

preg_match('/Duration: (.*?),/', $duration, $matches);

$duration = $matches[1];

// debug ("Duration: ", $duration);

$duration_array = split(':', $duration);

$duration = $duration_array[0] * 3600 + $duration_array[1] * 60 + $duration_array[2];

$time = $duration * $percent / 100;

// debug (" Time: ", $time);

$time = intval($time/3600) . ":" . intval(($time-(intval($time/3600)*3600))/60) . ":" . sprintf("%01.3f", ($time-(intval($time/60)*60)));

// debug (" Time: ", $time);

}

$browser = (isset($_GET['browser'])) ? strval($_GET['browser']) : 'true';

// debug (" Browser: ", $browser);

if ($browser == "true")

{

header('Content-Type: image/png');

exec("/usr/bin/ffmpeg -vcodec png -i "" . $videofile . "" -ss " . $time . " -vframes 1 -f image2 -");

//header('Content-Type: image/jpeg');

//exec("/usr/bin/ffmpeg -vcodec mjpeg -i "" . $videofile . "" -ss " . $time . " -vframes 1 -f image2 -");

}

else

{

exec("/usr/bin/ffmpeg -vcodec png -i "" . $videofile . "" -ss " . $time . " -vframes 1 -f image2 "" . $image . ""%d.png");

//exec("/usr/bin/ffmpeg -vcodec mjpeg -i "" . $videofile . "" -ss " . $time . " -vframes 1 -f image2 "" . $image . ""%d.jpg");

}

?>

希望本文所述对大家的php程序设计有所帮助。