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 <p>本备忘清单是 <a href="https://ffmpeg.org/">FFmpeg</a> 中常见视频处理操作的备忘清单</p>
 </div></header><div class="menu-tocs"><div class="menu-btn"><svg aria-hidden="true" fill="currentColor" height="1em" width="1em" viewBox="0 0 16 16" version="1.1" data-view-component="true">
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-</svg></div><div class="menu-modal"><a aria-hidden="true" class="leve2 tocs-link" href="#参数参考">参数参考</a><a aria-hidden="true" class="leve3 tocs-link" href="#常用开关">常用开关</a><a aria-hidden="true" class="leve3 tocs-link" href="#音频">音频</a><a aria-hidden="true" class="leve3 tocs-link" href="#比特率">比特率</a><a aria-hidden="true" class="leve4 tocs-link" href="#视频">视频</a><a aria-hidden="true" class="leve2 tocs-link" href="#视频编辑">视频编辑</a><a aria-hidden="true" class="leve3 tocs-link" href="#裁剪">裁剪</a><a aria-hidden="true" class="leve3 tocs-link" href="#缩放">缩放</a><a aria-hidden="true" class="leve3 tocs-link" href="#视频帧速率">视频帧速率</a><a aria-hidden="true" class="leve3 tocs-link" href="#剪切视频部分">剪切视频部分</a><a aria-hidden="true" class="leve3 tocs-link" href="#h265-2-pass-编码">H265 2-pass 编码</a><a aria-hidden="true" class="leve3 tocs-link" href="#视频比特率设置">视频比特率设置</a><a aria-hidden="true" class="leve3 tocs-link" href="#固定旋转">固定旋转</a><a aria-hidden="true" class="leve3 tocs-link" href="#放慢视频速度">放慢视频速度</a><a aria-hidden="true" class="leve3 tocs-link" href="#缩放到特定宽度">缩放到特定宽度</a><a aria-hidden="true" class="leve2 tocs-link" href="#重新包装">重新包装</a><a aria-hidden="true" class="leve3 tocs-link" href="#提取音频流">提取音频流</a><a aria-hidden="true" class="leve3 tocs-link" href="#创建缩略图">创建缩略图</a><a aria-hidden="true" class="leve3 tocs-link" href="#处理-id3-标签">处理 id3 标签</a><a aria-hidden="true" class="leve3 tocs-link" href="#重新采样转换音频">重新采样/转换音频</a><a aria-hidden="true" class="leve3 tocs-link" href="#切换容器转换类型">切换容器(转换类型)</a><a aria-hidden="true" class="leve3 tocs-link" href="#音视频同步">音视频同步</a><a aria-hidden="true" class="leve3 tocs-link" href="#图片中的视频">图片中的视频</a><a aria-hidden="true" class="leve3 tocs-link" href="#将视频拆分为图像">将视频拆分为图像</a><a aria-hidden="true" class="leve3 tocs-link" href="#转换为-gif">转换为 Gif</a><a aria-hidden="true" class="leve3 tocs-link" href="#移除音频">移除音频</a><a aria-hidden="true" class="leve3 tocs-link" href="#字幕">字幕</a><a aria-hidden="true" class="leve3 tocs-link" href="#音量">音量</a><a aria-hidden="true" class="leve2 tocs-link" href="#另见">另见</a></div></div><div class="h1wrap-body"><div class="wrap h2body-exist"><div class="wrap-header h2wrap"><h2 id="参数参考"><a aria-hidden="true" tabindex="-1" href="#参数参考"><span class="icon icon-link"></span></a>参数参考</h2><div class="wrap-body">
-</div></div><div class="h2wrap-body"><div class="wrap h3body-not-exist"><div class="wrap-header h3wrap"><h3 id="常用开关"><a aria-hidden="true" tabindex="-1" href="#常用开关"><span class="icon icon-link"></span></a>常用开关</h3><div class="wrap-body">
+</svg></div><div class="menu-modal"><a aria-hidden="true" class="leve2 tocs-link" href="#ffmpeg-参考">FFmpeg 参考</a><a aria-hidden="true" class="leve3 tocs-link" href="#安装">安装</a><a aria-hidden="true" class="leve3 tocs-link" href="#示例">示例</a><a aria-hidden="true" class="leve3 tocs-link" href="#常用开关">常用开关</a><a aria-hidden="true" class="leve3 tocs-link" href="#音频">音频</a><a aria-hidden="true" class="leve3 tocs-link" href="#比特率">比特率</a><a aria-hidden="true" class="leve4 tocs-link" href="#视频">视频</a><a aria-hidden="true" class="leve2 tocs-link" href="#视频编辑">视频编辑</a><a aria-hidden="true" class="leve3 tocs-link" href="#裁剪">裁剪</a><a aria-hidden="true" class="leve3 tocs-link" href="#缩放">缩放</a><a aria-hidden="true" class="leve3 tocs-link" href="#视频帧速率">视频帧速率</a><a aria-hidden="true" class="leve3 tocs-link" href="#剪切视频部分">剪切视频部分</a><a aria-hidden="true" class="leve3 tocs-link" href="#h265-2-pass-编码">H265 2-pass 编码</a><a aria-hidden="true" class="leve3 tocs-link" href="#视频比特率设置">视频比特率设置</a><a aria-hidden="true" class="leve3 tocs-link" href="#固定旋转">固定旋转</a><a aria-hidden="true" class="leve3 tocs-link" href="#放慢视频速度">放慢视频速度</a><a aria-hidden="true" class="leve3 tocs-link" href="#缩放到特定宽度">缩放到特定宽度</a><a aria-hidden="true" class="leve2 tocs-link" href="#重新包装">重新包装</a><a aria-hidden="true" class="leve3 tocs-link" href="#提取音频流">提取音频流</a><a aria-hidden="true" class="leve3 tocs-link" href="#创建缩略图">创建缩略图</a><a aria-hidden="true" class="leve3 tocs-link" href="#处理-id3-标签">处理 id3 标签</a><a aria-hidden="true" class="leve3 tocs-link" href="#重新采样转换音频">重新采样/转换音频</a><a aria-hidden="true" class="leve3 tocs-link" href="#切换容器转换类型">切换容器(转换类型)</a><a aria-hidden="true" class="leve3 tocs-link" href="#音视频同步">音视频同步</a><a aria-hidden="true" class="leve3 tocs-link" href="#图片中的视频">图片中的视频</a><a aria-hidden="true" class="leve3 tocs-link" href="#将视频拆分为图像">将视频拆分为图像</a><a aria-hidden="true" class="leve3 tocs-link" href="#转换为-gif">转换为 Gif</a><a aria-hidden="true" class="leve3 tocs-link" href="#移除音频">移除音频</a><a aria-hidden="true" class="leve3 tocs-link" href="#字幕">字幕</a><a aria-hidden="true" class="leve3 tocs-link" href="#音量">音量</a><a aria-hidden="true" class="leve2 tocs-link" href="#另见">另见</a></div></div><div class="h1wrap-body"><div class="wrap h2body-exist"><div class="wrap-header h2wrap"><h2 id="ffmpeg-参考"><a aria-hidden="true" tabindex="-1" href="#ffmpeg-参考"><span class="icon icon-link"></span></a>FFmpeg 参考</h2><div class="wrap-body">
+</div></div><div class="h2wrap-body"><div class="wrap h3body-not-exist"><div class="wrap-header h3wrap"><h3 id="安装"><a aria-hidden="true" tabindex="-1" href="#安装"><span class="icon icon-link"></span></a>安装</h3><div class="wrap-body">
+<p>Linux</p>
+<pre><code class="code-highlight"><span class="code-line">$ apt-get install ffmpeg
+</span><span class="code-line">$ yum install ffmpeg
+</span></code></pre>
+<p>MacOS</p>
+<pre class="language-bash"><code class="language-bash code-highlight"><span class="code-line">$ brew <span class="token function">install</span> ffmpeg
+</span></code></pre>
+</div></div></div><div class="wrap h3body-not-exist"><div class="wrap-header h3wrap"><h3 id="示例"><a aria-hidden="true" tabindex="-1" href="#示例"><span class="icon icon-link"></span></a>示例</h3><div class="wrap-body">
+<p>mp4 转 avi:</p>
+<pre class="language-bash"><code class="language-bash code-highlight"><span class="code-line">$ ffmpeg <span class="token parameter variable">-i</span> input.mp4 output.avi
+</span></code></pre>
+<p>webm 转 mp4:</p>
+<pre class="language-bash"><code class="language-bash code-highlight"><span class="code-line">$ ffmpeg <span class="token parameter variable">-i</span> movie.webm movie.mp4
+</span></code></pre>
+</div></div></div><div class="wrap h3body-not-exist"><div class="wrap-header h3wrap"><h3 id="常用开关"><a aria-hidden="true" tabindex="-1" href="#常用开关"><span class="icon icon-link"></span></a>常用开关</h3><div class="wrap-body">
 <pre class="language-bash"><code class="language-bash code-highlight"><span class="code-line"><span class="token parameter variable">-codecs</span>   <span class="token comment"># 列出编解码器</span>
 </span><span class="code-line"><span class="token parameter variable">-c:v</span>      <span class="token comment"># 视频编解码器(-vcodec)-'copy'复制流</span>
 </span><span class="code-line"><span class="token parameter variable">-c:a</span>      <span class="token comment"># 音频编解码器(-acodec)</span>