ffmpeg 解码视频小例子

心已赠人 2022-07-21 05:53 177阅读 0赞

原：http://blog.csdn.net/flyfight88/article/details/8541068

ffmpeg是编解码的利器，用了很久，以前看过[dranger][] 的教程，非常精彩，受益颇多，是学习ffmpeg api很好的材料。可惜的是其针对的ffmpeg版本已经比较老了，而ffmpeg的更新又很快，有些API已经完全换掉了，导致dranger教程中的 代码已经无法编译，正好最近需要使用ffmpeg，于是就利用dranger的教程和代码，自己边学边记录，于是也就有了这个所谓的 New FFmpeg Tutorial，希望对学习ffmpeg的人有所帮助。

source code：[videoframe.c][]

### 视频播放过程 ###

首先简单介绍以下视频文件的相关知识。我们平时看到的视频文件有许多格式，比如 avi， mkv， rmvb， mov， mp4等等，这些被称为[容器][Link 1]（[Container][]）， 不同的容器格式规定了其中音视频数据的组织方式（也包括其他数据，比如字幕等）。容器中一般会封装有视频和音频轨，也称为视频流（stream）和音频 流，播放视频文件的第一步就是根据视频文件的格式，解析（demux）出其中封装的视频流、音频流以及字幕（如果有的话），解析的数据读到包 （packet）中，每个包里保存的是视频帧（frame）或音频帧，然后分别对视频帧和音频帧调用相应的解码器（decoder）进行解码，比如使用 H.264编码的视频和MP3编码的音频，会相应的调用H.264解码器和MP3解码器，解码之后得到的就是原始的图像(YUV or RGB)和声音(PCM)数据，然后根据同步好的时间将图像显示到屏幕上，将声音输出到声卡，最终就是我们看到的视频。

FFmpeg的API就是根据这个过程设计的，因此使用FFmpeg来处理视频文件的方法非常直观简单。下面就一步一步介绍从视频文件中解码出图片的过程。

### 声明变量 ###

首先定义整个过程中需要使用到的变量：

<table> 
 <tbody> 
  <tr> 
   <td><code>01</code></td> 
   <td><code>int</code>&nbsp;<code>main(</code><code>int</code>&nbsp;<code>argc,&nbsp;</code><code>const</code>&nbsp;<code>char</code>&nbsp;<code>*argv[])</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>03</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>AVFormatContext *pFormatCtx = NULL;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>04</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>int</code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<code>i, videoStream;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>05</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>AVCodecContext&nbsp; *pCodecCtx;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>06</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>AVCodec&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; *pCodec;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>07</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>AVFrame&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; *pFrame;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>08</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>AVFrame&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; *pFrameRGB;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>09</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>AVPacket&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; packet;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>10</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>int</code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<code>frameFinished;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>11</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>int</code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<code>numBytes;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>12</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>uint8_t&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; *buffer;</code></td> 
  </tr> 
 </tbody> 
</table>

*  [AVFormatContext][]：保存需要读入的文件的格式信息，比如流的个数以及流数据等
 *  [AVCodecCotext][]：保存了相应流的详细编码信息，比如视频的宽、高，编码类型等。
 *  [pCodec][]：真正的编解码器，其中有编解码需要调用的函数
 *  [AVFrame][]：用于保存数据帧的数据结构，这里的两个帧分别是保存颜色转换前后的两帧图像
 *  [AVPacket][]：解析文件时会将音/视频帧读入到packet中

### 打开文件 ###

接下来我们打开一个视频文件。

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>av_register_all();</code></td> 
  </tr> 
 </tbody> 
</table>

[av\_register\_all][av_register_all] 定义在 [libavformat][] 里，调用它用以注册所有支持的文件格式以及编解码器，从其[实现代码][Link 2]里可以看到它会调用 avcodec\_register\_all，因此之后就可以用所有ffmpeg支持的codec了。

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>if</code><code>( avformat_open_input(&amp;pFormatCtx, argv[1], NULL, NULL) != 0 )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>2</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>-1;</code></td> 
  </tr> 
 </tbody> 
</table>

使用新的API [avformat\_open\_input][avformat_open_input]来打开一个文件，第一个参数是一个AVFormatContext指针变量的地址，它会根据打开的文件信息填充AVFormatContext，***需要注意的是，此处的pFormatContext必须为NULL或由[avformat\_alloc\_context][avformat_alloc_context]分配得到***，这也是上一节中将其初始化为NULL的原因，否则此函数调用会出问题。第二个参数是打开的文件名，通过argv\[1\]指定，也就是命令行的第一个参数。后两个参数分别用于指定特定的输入格式（[AVInputFormat][]）以及指定文件打开额外参数的[AVDictionary][]结构，这里均留作NULL。

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>if</code><code>( avformat_find_stream_info(pFormatCtx, NULL ) &lt; 0 )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>2</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>-1;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>4</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>av_dump_format(pFormatCtx, -1, argv[1], 0);</code></td> 
  </tr> 
 </tbody> 
</table>

[avformat\_open\_input][avformat_open_input 1]函数只是读文件头，并不会填充流信息，因此我们需要接下来调用[avformat\_find\_stream\_info][avformat_find_stream_info]获取文件中的流信息，此函数会读取packet，并确定文件中所有的流信息，设置pFormatCtx->streams指向文件中的流，但此函数并不会改变文件指针，读取的packet会给后面的解码进行处理。  
最后调用一个帮助函数[av\_dump\_format][av_dump_format]，输出文件的信息，也就是我们在使用ffmpeg时能看到的文件详细信息。第二个参数指定输出哪条流的信息，-1表示给ffmpeg自己选择。最后一个参数用于指定dump的是不是输出文件，我们dump的是输入文件，因此一定要是0。

现在 pFormatCtx->streams 中已经有所有流了，因此现在我们遍历它找到第一条视频流:

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>videoStream = -1;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>2</code></td> 
   <td><code>for</code><code>( i = 0; i &lt; pFormatCtx-&gt;nb_streams; i++ )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>3</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>if</code><code>( pFormatCtx-&gt;streams[i]-&gt;codec-&gt;codec_type == AVMEDIA_TYPE_VIDEO) { </code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>4</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>videoStream = i;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>5</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>break</code><code>;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>8</code></td> 
   <td><code>if</code><code>( videoStream == -1 )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>9</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>-1;</code></td> 
  </tr> 
 </tbody> 
</table>

codec\_type 的宏定义已经由以前的 CODEC\_TYPE\_VIDEO 改为 AVMEDIA\_TYPE\_VIDEO 了。接下来我们通过这条 video stream 的编解码信息打开相应的解码器：

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>pCodecCtx = pFormatCtx-&gt;streams[videoStream]-&gt;codec;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>3</code></td> 
   <td><code>pCodec = avcodec_find_decoder(pCodecCtx-&gt;codec_id);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>4</code></td> 
   <td><code>if</code><code>( pCodec == NULL )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>5</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>-1;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>7</code></td> 
   <td><code>if</code><code>( avcodec_open2(pCodecCtx, pCodec, NULL) &lt; 0 )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>8</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>-1;</code></td> 
  </tr> 
 </tbody> 
</table>

### 分配图像缓存 ###

接下来我们准备给即将解码的图片分配内存空间。

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>pFrame = avcodec_alloc_frame();</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>2</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>if</code><code>( pFrame == NULL )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>3</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>-1;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>5</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>pFrameRGB = avcodec_alloc_frame();</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>6</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>if</code><code>( pFrameRGB == NULL )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>7</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>-1;</code></td> 
  </tr> 
 </tbody> 
</table>

调用 [avcodec\_alloc\_frame][avcodec_alloc_frame] 分配帧，因为最后我们会将图像写成 24-bits RGB 的 PPM 文件，因此这里需要两个 AVFrame，pFrame用于存储解码后的数据，pFrameRGB用于存储转换后的数据:

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>numBytes = avpicture_get_size(PIX_FMT_RGB24, pCodecCtx-&gt;width,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>2</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>pCodecCtx-&gt;height);</code></td> 
  </tr> 
 </tbody> 
</table>

这里调用 [avpicture\_get\_size][avpicture_get_size]，根据 pCodecCtx 中原始图像的宽高计算 RGB24 格式的图像需要占用的空间大小，这是为了之后给 pFrameRGB 分配空间:

<table> 
 <tbody> 
  <tr> 
   <td><code>1</code></td> 
   <td><code>buffer = av_malloc(numBytes);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>3</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>avpicture_fill( (AVPicture *)pFrameRGB, buffer, PIX_FMT_RGB24,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>4</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>pCodecCtx-&gt;width, pCodecCtx-&gt;height);</code></td> 
  </tr> 
 </tbody> 
</table>

接着上面的，首先是用 [av\_malloc][av_malloc] 分配上面计算大小的内存空间，然后调用 [avpicture\_fill][avpicture_fill] 将 pFrameRGB 跟 buffer 指向的内存关联起来。

### 获取图像 ###

OK，一切准备好就可以开始从文件中读取视频帧并解码得到图像了。

<table> 
 <tbody> 
  <tr> 
   <td><code>02</code></td> 
   <td><code>while</code><code>( av_read_frame(pFormatCtx, &amp;packet) &gt;= 0 ) { </code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>03</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>if</code><code>( packet.stream_index == videoStream ) { </code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>04</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>avcodec_decode_video2(pCodecCtx, pFrame, &amp;frameFinished, &amp;packet);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>06</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>if</code><code>( frameFinished ) { </code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>07</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>struct</code>&nbsp;<code>SwsContext *img_convert_ctx = NULL;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>08</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>img_convert_ctx =</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>09</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>sws_getCachedContext(img_convert_ctx, pCodecCtx-&gt;width,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>10</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>pCodecCtx-&gt;height, pCodecCtx-&gt;pix_fmt,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>11</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>pCodecCtx-&gt;width, pCodecCtx-&gt;height,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>12</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>PIX_FMT_RGB24, SWS_BICUBIC,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>14</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>if</code><code>( !img_convert_ctx ) { </code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>15</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>fprintf</code><code>(stderr,&nbsp;</code><code>"Cannot initialize sws conversion context\n"</code><code>);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>18</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>sws_scale(img_convert_ctx, (</code><code>const</code>&nbsp;<code>uint8_t*&nbsp;</code><code>const</code><code>*)pFrame-&gt;data,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>19</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>pFrame-&gt;linesize, 0, pCodecCtx-&gt;height, pFrameRGB-&gt;data,</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>20</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>pFrameRGB-&gt;linesize);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>22</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>SaveFrame(pFrameRGB, pCodecCtx-&gt;width, pCodecCtx-&gt;height, i);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>25</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>av_free_packet(&amp;packet);</code></td> 
  </tr> 
 </tbody> 
</table>

[av\_read\_frame][av_read_frame] 从文件中读取一个packet，对于视频来说一个packet里面包含一帧图像数据，音频可能包含多个帧（当音频帧长度固定时），读到这一帧后，如果是视频帧，则使用 [avcodec\_decode\_video2][avcodec_decode_video2] 对packet中的帧进行解码，有时候解码器并不能从一个packet中解码得到一帧图像数据（比如在需要其他参考帧的情况下），因此会设置 frameFinished，如果已经得到下一帧图像则设置 frameFinished 非零，否则为零。所以这里我们判断 frameFinished 是否为零来确定 pFrame 中是否已经得到解码的图像。注意在每次处理完后需要调用 [av\_free\_packet][av_free_packet] 释放读取的packet。

解码得到图像后，很有可能不是我们想要的 RGB24 格式，因此需要使用 [swscale][] 来做转换，调用 [sws\_getCachedContext][sws_getCachedContext] 得到转换上下文，使用[sws\_scale][sws_scale] 将图形从解码后的格式转换为 RGB24，最后将前50帧写人 ppm 文件。最后释放图像以及关闭文件：

<table> 
 <tbody> 
  <tr> 
   <td><code>01</code></td> 
   <td><code>av_free(buffer);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>02</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>av_free(pFrameRGB);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>03</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>av_free(pFrame);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>04</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>avcodec_close(pCodecCtx);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>05</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>avformat_close_input(&amp;pFormatCtx);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>07</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>return</code>&nbsp;<code>0;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>10</code></td> 
   <td><code>static</code>&nbsp;<code>void</code>&nbsp;<code>SaveFrame(AVFrame *pFrame,&nbsp;</code><code>int</code>&nbsp;<code>width,&nbsp;</code><code>int</code>&nbsp;<code>height,&nbsp;</code><code>int</code>&nbsp;<code>iFrame)</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>12</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>FILE</code>&nbsp;<code>*pFile;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>13</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>char</code>&nbsp;<code>szFilename[32];</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>16</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>sprintf</code><code>(szFilename,&nbsp;</code><code>"frame%d.ppm"</code><code>, iFrame);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>17</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>pFile =&nbsp;</code><code>fopen</code><code>(szFilename,&nbsp;</code><code>"wb"</code><code>);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>18</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>if</code><code>( !pFile )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>19</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>return</code><code>;</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>20</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>fprintf</code><code>(pFile,&nbsp;</code><code>"P6\n%d %d\n255\n"</code><code>, width, height);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>22</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>for</code><code>( y = 0; y &lt; height; y++ )</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>23</code></td> 
   <td><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>fwrite</code><code>(pFrame-&gt;data[0] + y * pFrame-&gt;linesize[0], 1, width * 3, pFile);</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <td><code>25</code></td> 
   <td><code>&nbsp;&nbsp;</code><code>fclose</code><code>(pFile);</code></td> 
  </tr> 
 </tbody> 
</table>

<table style="color:rgb(0,0,0); font-family:Arial; font-size:14px; line-height:26px"> 
 <tbody> 
  <tr> 
   <td><code>26</code></td> 
   <td> <p style="margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px"> <code>}</code></p> <p style="margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px"> <br> <code></code></p> <p style="margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px"> <br> <code></code></p> <p style="margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px"> <br> <code></code></p> <p style="margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px"> <br> <code></code></p> <p style="margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px"> <code></code></p> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit"><span style="margin:0px; padding:0px; border:none; color:gray; background-color:inherit">#include&nbsp;&lt;libavcodec/avcodec.h&gt;</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit"><span style="margin:0px; padding:0px; border:none; color:gray; background-color:inherit">#include&nbsp;&lt;libavutil/avutil.h&gt;</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;</span></span></li> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit"><span style="margin:0px; padding:0px; border:none; color:gray; background-color:inherit">#include&nbsp;&lt;stdio.h&gt;</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit"><span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">static</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;</span><span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">void</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;SaveFrame(AVFrame&nbsp;*pFrame,&nbsp;</span><span style="margin:0px; padding:0px; border:none; color:rgb(255,153,51); font-weight:bold; background-color:inherit">int</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;width,&nbsp;</span><span style="margin:0px; padding:0px; border:none; color:rgb(255,153,51); font-weight:bold; background-color:inherit">int</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;height,&nbsp;</span><span style="margin:0px; padding:0px; border:none; color:rgb(255,153,51); font-weight:bold; background-color:inherit">int</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;iFrame)&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">{&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(255,153,51); font-weight:bold; background-color:inherit">FILE</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;*pFile;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(255,153,51); font-weight:bold; background-color:inherit">char</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;szFilename[32];&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(255,153,51); font-weight:bold; background-color:inherit">int</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;y;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;sprintf(szFilename,&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(137,211,54); background-color:inherit">"frame%d.ppm"</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">,&nbsp;iFrame);&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;pFile&nbsp;=&nbsp;fopen(szFilename,&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(137,211,54); background-color:inherit">"wb"</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">);&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(!pFile)&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">;&nbsp;&nbsp;</span></span></li> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;</span></li> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">{&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit"><span style="margin:0px; padding:0px; border:none; color:gray; background-color:inherit">#if&nbsp;1&nbsp;</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;AVFormatContext&nbsp;*pFormatCtx&nbsp;=&nbsp;NULL;&nbsp;&nbsp;</span></li> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;AVCodecContext&nbsp;*pCodecCtx;&nbsp;&nbsp;</span></li> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;AVFrame&nbsp;*pFrame;&nbsp;&nbsp;</span></li> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;AVPacket&nbsp;packet;&nbsp;&nbsp;</span></li> 
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      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;uint8_t&nbsp;*buffer;&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit"><span style="margin:0px; padding:0px; border:none; color:gray; background-color:inherit">#endif&nbsp;&nbsp;</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;av_register_all();&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(avformat_open_input(&amp;pFormatCtx,&nbsp;argv[1],&nbsp;NULL,&nbsp;NULL)&nbsp;!=&nbsp;0)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;-1;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(avformat_find_stream_info(pFormatCtx,&nbsp;NULL)&nbsp;&lt;&nbsp;0)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;-1;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;av_dump_format(pFormatCtx,&nbsp;-1,&nbsp;argv[1],&nbsp;0);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;videoStream&nbsp;=&nbsp;-1;&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">for</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(i=0;&nbsp;i&lt;pFormatCtx-&gt;nb_streams;&nbsp;i++)&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(pFormatCtx-&gt;streams[i]-&gt;codec-&gt;codec_type&nbsp;==&nbsp;AVMEDIA_TYPE_VIDEO)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;videoStream&nbsp;=&nbsp;i;&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">break</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(videoStream&nbsp;==&nbsp;-1)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;-1;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;pCodecCtx&nbsp;=&nbsp;pFormatCtx-&gt;streams[videoStream]-&gt;codec;&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;pCodec&nbsp;=&nbsp;avcodec_find_decoder(pCodecCtx-&gt;codec_id);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(pCodec&nbsp;==&nbsp;NULL)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;-1;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(avcodec_open2(pCodecCtx,&nbsp;pCodec,&nbsp;NULL)&nbsp;&lt;&nbsp;0)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;-1;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;pFrame&nbsp;=&nbsp;avcodec_alloc_frame();&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(pFrame&nbsp;==&nbsp;NULL)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;-1;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;pFrameRGB&nbsp;=&nbsp;avcodec_alloc_frame();&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(pFrameRGB&nbsp;==&nbsp;NULL)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;-1;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;numBytes&nbsp;=&nbsp;avpicture_get_size(PIX_FMT_RGB24,&nbsp;pCodecCtx-&gt;width,&nbsp;pCodecCtx-&gt;height);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;buffer&nbsp;=&nbsp;av_malloc(numBytes);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;avpicture_fill((AVPicture&nbsp;*)pFrameRGB,&nbsp;buffer,&nbsp;PIX_FMT_RGB24,&nbsp;pCodecCtx-&gt;width,&nbsp;pCodecCtx-&gt;height);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;i&nbsp;=&nbsp;0;&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">while</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(av_read_frame(pFormatCtx,&nbsp;&amp;packet)&nbsp;&gt;=0)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(packet.stream_index&nbsp;==&nbsp;videoStream)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;avcodec_decode_video2(pCodecCtx,&nbsp;pFrame,&nbsp;&amp;frameFinished,&nbsp;&amp;packet);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(frameFinished)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">struct</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;SwsContext&nbsp;*img_convert_ctx&nbsp;=&nbsp;NULL;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;img_convert_ctx&nbsp;=&nbsp;sws_getCachedContext(img_convert_ctx,&nbsp;pCodecCtx-&gt;width,&nbsp;pCodecCtx-&gt;height,&nbsp;pCodecCtx-&gt;pix_fmt,&nbsp;pCodecCtx-&gt;width,&nbsp;pCodecCtx-&gt;height,&nbsp;PIX_FMT_RGB24,&nbsp;SWS_BICUBIC,&nbsp;NULL,&nbsp;NULL,&nbsp;NULL);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(!img_convert_ctx)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;fprintf(stderr,&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(137,211,54); background-color:inherit">"Cannot&nbsp;initialize&nbsp;sws&nbsp;conversion&nbsp;context\n"</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">);&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;exit(1);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;sws_scale(img_convert_ctx,(<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">const</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;uint8_t&nbsp;*&nbsp;</span><span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">const</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;*)pFrame-&gt;data,&nbsp;pFrame-&gt;linesize,&nbsp;0&nbsp;,&nbsp;pCodecCtx-&gt;height,&nbsp;pFrameRGB-&gt;data,&nbsp;pFrameRGB-&gt;linesize);&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">if</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">(i++&nbsp;&lt;&nbsp;50)&nbsp;{&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;SaveFrame(pFrameRGB,&nbsp;pCodecCtx-&gt;width,&nbsp;pCodecCtx-&gt;height,&nbsp;i);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;av_free_packet(&amp;packet);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;av_free(buffer);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;av_free(pFrameRGB);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;av_free(pFrame);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;avcodec_close(pCodecCtx);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;avformat_close_input(&amp;pFormatCtx);&nbsp;&nbsp;</span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px; color:inherit"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;&nbsp;&nbsp;&nbsp;<span style="margin:0px; padding:0px; border:none; color:rgb(51,153,255); font-weight:bold; background-color:inherit">return</span><span style="margin:0px; padding:0px; border:none; background-color:inherit">&nbsp;0;&nbsp;&nbsp;</span></span></li> 
      <li style="margin:0px!important; padding:0px 3px 0px 10px!important; border:none; list-style:decimal-leading-zero outside; line-height:13.199999809265137px"> <span style="margin:0px; padding:0px; border:none; background-color:inherit">} &nbsp;</span></li> 
     </ol> 
    </div> </td> 
  </tr> 
 </tbody> 
</table>

[dranger]: http://dranger.com/ffmpeg/ffmpeg.html
[videoframe.c]: http://justlaputa.com/wp-content/uploads/2012/01/videoframe.c
[Link 1]: http://en.wikipedia.org/wiki/Digital_container_format
[Container]: http://wiki.multimedia.cx/index.php?title=Category:Container_Formats
[AVFormatContext]: http://ffmpeg.org/doxygen/trunk/structAVFormatContext.html
[AVCodecCotext]: http://ffmpeg.org/doxygen/trunk/structAVCodecContext.html
[pCodec]: http://ffmpeg.org/doxygen/trunk/structAVCodec.html
[AVFrame]: http://ffmpeg.org/doxygen/trunk/structAVFrame.html
[AVPacket]: http://ffmpeg.org/doxygen/trunk/structAVPacket.html
[av_register_all]: http://ffmpeg.org/doxygen/trunk/group__lavf__core.html#g917265caec45ef5a0646356ed1a507e3
[libavformat]: http://ffmpeg.org/doxygen/trunk/avformat_8h.html
[Link 2]: http://ffmpeg.org/doxygen/trunk/allformats_8c-source.html#l00040
[avformat_open_input]: http://ffmpeg.org/doxygen/trunk/group__lavf__decoding.html#g10a404346c646e4ab58f4ed798baca32
[avformat_alloc_context]: http://ffmpeg.org/doxygen/trunk/group__lavf__core.html#gc7a91abf2f59648d995894711f070f62
[AVInputFormat]: http://ffmpeg.org/doxygen/trunk/structAVInputFormat.html
[AVDictionary]: http://ffmpeg.org/doxygen/trunk/structAVDictionary.html
[avformat_open_input 1]: http://ffmpeg.org/doxygen/trunk/libavformat_2utils_8c-source.html#l00660
[avformat_find_stream_info]: http://ffmpeg.org/doxygen/trunk/group__lavf__decoding.html#gd42172e27cddafb81096939783b157bb
[av_dump_format]: http://ffmpeg.org/doxygen/trunk/group__lavf__misc.html#ge2645941f2dc779c307eb6314fd39f10
[avcodec_alloc_frame]: http://ffmpeg.org/doxygen/trunk/libavcodec_2avcodec_8h.html#d5f9212dec34c9fff0124171fa684a18
[avpicture_get_size]: http://ffmpeg.org/doxygen/trunk/libavcodec_2avcodec_8h.html#c35e88cdafc18d57d131c7642615377d
[av_malloc]: http://ffmpeg.org/doxygen/trunk/group__lavu__mem.html#gcbca30ebc510a7e4156d66e7aceb2dc8
[avpicture_fill]: http://ffmpeg.org/doxygen/trunk/libavcodec_2avcodec_8h.html#54da074edd8339905bc90b75b1402d4a
[av_read_frame]: http://ffmpeg.org/doxygen/trunk/group__lavf__decoding.html#g4fdb3084415a82e3810de6ee60e46a61
[avcodec_decode_video2]: http://ffmpeg.org/doxygen/trunk/libavcodec_2avcodec_8h.html#3e4048fd6893d4a001bdaa3d251f3c03
[av_free_packet]: http://ffmpeg.org/doxygen/trunk/libavcodec_2avcodec_8h.html#e65881462e78f98b268f34661d921ee0
[swscale]: http://ffmpeg.org/doxygen/trunk/swscale_8h.html
[sws_getCachedContext]: http://ffmpeg.org/doxygen/trunk/swscale_8h.html#2e12a713a6ac7b1cf96e17c4c049ab15
[sws_scale]: http://ffmpeg.org/doxygen/trunk/swscale_8h.html#e531c9754c9205d90ad6800015046d74