https://www.mawenqian.com/zh/tags/ffmpeg/ Recent content in Ffmpeg on 极客Vinkey https://www.mawenqian.com/images/papermod-cover.png https://www.mawenqian.com/images/papermod-cover.png Hugo zh-CN MA Wenqian · mawenqian.com Mon, 23 May 2022 21:26:01 +0000 https://www.mawenqian.com/zh/ffmpeg-tool-share/ Mon, 23 May 2022 21:26:01 +0000 https://www.mawenqian.com/zh/ffmpeg-tool-share/ <h1 id="ffmpeg使用说明">FFmpeg使用说明</h1> <h2 id="简介">简介</h2> <p><a href="https://ffmpeg.org">FFmpeg</a>是一个跨平台可录制、转换、流式传输音视频工具。（自已从官网翻译的）</p> <p><a href="https://ffmpeg.org/ffmpeg.html">用户文档</a></p> <h2 id="图片处理">图片处理</h2> <h3 id="查看图像信息">查看图像信息</h3> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">ffprobe image_source </span></span><span class="line"><span class="cl"><span class="c1">#查看图像尺寸等信息</span> </span></span></code></pre></div><h3 id="图片压缩">图片压缩</h3> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">ffmpeg -i image_source -q compress_level out_source </span></span><span class="line"><span class="cl"><span class="c1">#compress_level：压缩等级为正整数，数值越大压缩等级越高</span> </span></span></code></pre></div><h3 id="约束比例压缩">约束比例压缩</h3> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">ffmpeg -i image_source -vf <span class="nv">scale</span><span class="o">=</span>width:height out_source </span></span><span class="line"><span class="cl"><span class="c1">#width为压缩后的图片宽度</span> </span></span><span class="line"><span class="cl"><span class="c1">#height为压缩后的图片高度</span> </span></span><span class="line"><span class="cl"><span class="c1">#当width或height其中有一个数值为-1时将保持原来图片尺寸比例压缩</span> </span></span></code></pre></div><h3 id="图片裁剪">图片裁剪</h3> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">ffmpeg -i image_source -vf <span class="nv">crop</span><span class="o">=</span>width:height:from_x:from_y out_source </span></span><span class="line"><span class="cl"><span class="c1">#width是要裁剪出的图片的宽度</span> </span></span><span class="line"><span class="cl"><span class="c1">#height是要裁剪出的图片的高度</span> </span></span><span class="line"><span class="cl"><span class="c1">#from_x是裁剪的起始X轴的位置</span> </span></span><span class="line"><span class="cl"><span class="c1">#from_y是裁剪的起始Y轴的位置</span> </span></span><span class="line"><span class="cl"><span class="c1">#如果不指定from_x和from_y表示从原始图片中心位置开始裁剪</span> </span></span></code></pre></div><h2 id="示例">示例</h2> <p>这个场景来源于我在课题组做推送，我进行视频分享时会录制gif动图，因为文案每次都是轮流写的，不同人有不同的录制方式，导致有时录屏转的文件格式很大（可能有15MB），但微信推送图片最大是10MB，所以必须进行压缩。</p> <p>最简单的办法就是，直接转换录制的视频或者已经压缩后的超大gif文件，附件给了2个mov文件。</p> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">ffmpeg -i 1.mov 1-1.gif </span></span><span class="line"><span class="cl">ffmpeg -i 1.mov -vf <span class="nv">scale</span><span class="o">=</span>500:-1 1-2.gif </span></span></code></pre></div><p><strong>附件下载</strong></p> <p><a href="https://www.mawenqian.com/download/2022/ffmpeg-test202207.zip">ffmpeg-test202207.zip</a></p> <p><strong>参考资料</strong></p> <ol> <li><a href="https://www.jianshu.com/p/b53943fc3819">FFmpeg&mdash;-图片处理</a></li> </ol>