Php-ffmpeg“未知编码器libfaac”在Windows上

我使用的是laravel 4.2。

我正在做一个项目，用户可以上传视频，我需要对其进行转码，以便在所有类型的设备上播放。

对于代码转换，我在项目中添加了来自github的php-fmpeg包。根据说明，我已从http://ffmpeg.zeranoe.com/builds并将ffmpeg.exe的路径设置为环境变量path。

现在，我尝试了以下代码来对上传的视频进行转码：

$ffmpeg = FFMpeg'FFMpeg::create();
$video = $ffmpeg->open($video_path);
$format = new FFMpeg'Format'Video'X264();
$format->setKiloBitrate(1000)
        ->setAudioChannels(2)
        ->setAudioKiloBitrate(256);
$video->save($format, public_path().$path.$save_filename);

但它给出的错误如下：

[ERROR] ffmpeg version N-70767-gd24af70 Copyright (c) 2000-2015 the FFmpeg developers
[ERROR]   built with gcc 4.9.2 (GCC)
[ERROR]   configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
[ERROR]   libavutil      54. 20.100 / 54. 20.100
[ERROR]   libavcodec     56. 28.100 / 56. 28.100
[ERROR]   libavformat    56. 25.101 / 56. 25.101
[ERROR]   libavdevice    56.  4.100 / 56.  4.100
[ERROR]   libavfilter     5. 12.100 /  5. 12.100
[ERROR]   libswscale      3.  1.101 /  3.  1.101
[ERROR]   libswresample   1.  1.100 /  1.  1.100
[ERROR]   libpostproc    53.  3.100 / 53.  3.100
[ERROR] 
[ERROR] Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'http://localhost/ohvideo-ftp/public/temp/5ZPlIuU1AIgz8RR4p0bs.mp4':
[ERROR]   Metadata:
[ERROR]     major_brand     : mp42
[ERROR]     minor_version   : 0
[ERROR]     compatible_brands: mp42mp41isomavc1
[ERROR]     creation_time   : 2013-11-09 00:29:52
[ERROR]   Duration: 00:00:30.12, start: 0.000000, bitrate: 417 kb/s
[ERROR]     Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 320x240 [SAR 1:1 DAR 4:3], 381 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
[ERROR]     Metadata:
[ERROR]       creation_time   : 2013-11-09 00:29:52
[ERROR]       handler_name    : L-SMASH Video Handler
[ERROR]       encoder         : AVC Coding
[ERROR]     Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 32 kb/s (default)
[ERROR]     Metadata:
[ERROR]       creation_time   : 2013-11-09 00:29:52
[ERROR]       handler_name    : L-SMASH Audio Handler
[ERROR] Unknown encoder 'libfaac'
[ERROR] 
{"error":{"type":"FFMpeg''Exception''RuntimeException","message":"Encoding failed","file":"F:''wamp''www''ohvideo-ftp''vendor''php-ffmpeg''php-ffmpeg''src''FFMpeg''Media''Video.php","line":168}}

在搜索了很多之后，我在这里找到了解决方案的链接，并注意到

Zeranoe的ffmpeg不包含libfaac支持，因为该编码器required-enable nonfree，这将导致不可再分发建筑

我不知道答案。有人能帮我克服这个吗？

编辑：（工作代码如下）

我创建了一个CustomVideo类，与FFMpeg'Format'Video'X264()类相同，如下所示：

class CustomVideo extends FFMpeg'Format'Video'DefaultVideo
{
    /** @var boolean */
    private $bframesSupport = true;
    public function __construct($audioCodec = 'libmp3lame', $videoCodec = 'libx264')
    {
        $this
            ->setAudioCodec($audioCodec)
            ->setVideoCodec($videoCodec);
    }
    /**
     * {@inheritDoc}
     */
    public function supportBFrames()
    {
        return $this->bframesSupport;
    }
    /**
     * @param $support
     *
     * @return X264
     */
    public function setBFramesSupport($support)
    {
        $this->bframesSupport = $support;
        return $this;
    }
    /**
     * {@inheritDoc}
     */
    public function getAvailableAudioCodecs()
    {
        return array('libmp3lame');
    }
    /**
     * {@inheritDoc}
     */
    public function getAvailableVideoCodecs()
    {
        return array('libx264');
    }
    /**
     * {@inheritDoc}
     */
    public function getPasses()
    {
        return 2;
    }
    /**
     * @return int
     */
    public function getModulus()
    {
        return 2;
    }
}

并更新代码以将视频转码如下：

$ffmpeg = FFMpeg'FFMpeg::create();
$video = $ffmpeg->open($video_path);
$format = new CustomVideo();
$format->setKiloBitrate(1000)
       ->setAudioChannels(2)
       ->setAudioKiloBitrate(256);
$video->save($format, public_path().$path.$save_filename); 

解决了Unknown encoder libfaac错误。