create: 下载 fMP4 时要带上 init.mp4

MemRelay-Operation: memory-save:rapt-hls-init-mp4-20260927
MemRelay-Resource: 39637cf5-8f58-487f-aea2-6a11244396d3

projects/280dd2a0-d23d-4a71-91e1-dce4353163be/下载 fMP4 时要带上 init.mp4.md

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+---
+title: 下载 fMP4 时要带上 init.mp4
+type: experience
+permalink: main/projects/280dd2a0-d23d-4a71-91e1-dce4353163be/下载-f-mp4-时要带上-init.mp4
+stable_id: 39637cf5-8f58-487f-aea2-6a11244396d3
+scope: project
+memory_type: experience
+project_id: 280dd2a0-d23d-4a71-91e1-dce4353163be
+usage_profile_id: 0c9feb46-d06e-43cd-9ef0-c5813c84a998
+status: active
+revision: 1
+request_id: rapt-hls-init-mp4-20260927
+created_at: '2026-09-27T07:11:47.412845+00:00'
+updated_at: '2026-09-27T07:11:47.412845+00:00'
+tags:
+- downloads
+- hls
+---
+
+fMP4 播放列表的 init.mp4 写在 #EXT-X-MAP:URI 里，不在分片行上。下载若只保存非注释行，ffmpeg 转 MP4 会报 Opening init.mp4 / video1.m4s No such file or directory。localize_media 会把 MAP 和 EXT-X-KEY 的 URI 一并下载，并改写成本地文件名。失败的那一集要在重启桌面端后继续下载才会走新逻辑。