knpwrs's questions

给定输入视频，input.mp4以下命令会生成一个out文件夹，其中包含一堆 HLS 视频片段和m3u8多种分辨率的播放列表文件：

ffmpeg -hide_banner -y -i input.mp4 \
  -vf scale=w=640:h=360:force_original_aspect_ratio=decrease -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4 -hls_playlist_type vod  -b:v 800k -maxrate 856k -bufsize 1200k -b:a 96k -hls_segment_filename out/360p_%03d.ts out/360p.m3u8 \
  -vf scale=w=842:h=480:force_original_aspect_ratio=decrease -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4 -hls_playlist_type vod -b:v 1400k -maxrate 1498k -bufsize 2100k -b:a 128k -hls_segment_filename out/480p_%03d.ts out/480p.m3u8 \
  -vf scale=w=1280:h=720:force_original_aspect_ratio=decrease -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4 -hls_playlist_type vod -b:v 2800k -maxrate 2996k -bufsize 4200k -b:a 128k -hls_segment_filename out/720p_%03d.ts out/720p.m3u8 \
  -vf scale=w=1920:h=1080:force_original_aspect_ratio=decrease -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4 -hls_playlist_type vod -b:v 5000k -maxrate 5350k -bufsize 7500k -b:a 192k -hls_segment_filename out/1080p_%03d.ts out/1080p.m3u8

运行上述命令时，输出如下所示：

[hls @ 0x12be06030] Opening 'out/360p_000.ts' for writing
[hls @ 0x12be088d0] Opening 'out/480p_000.ts' for writing
[hls @ 0x12be0b810] Opening 'out/720p_000.ts' for writing
[hls @ 0x12be0e790] Opening 'out/1080p_000.ts' for writing
[hls @ 0x12be06030] Opening 'out/360p_001.ts' for writing
[hls @ 0x12be088d0] Opening 'out/480p_001.ts' for writing
[hls @ 0x12be0b810] Opening 'out/720p_001.ts' for writing
[hls @ 0x12be0e790] Opening 'out/1080p_001.ts' for writing
[hls @ 0x12be06030] Opening 'out/360p_002.ts' for writing
[hls @ 0x12be088d0] Opening 'out/480p_002.ts' for writing
[hls @ 0x12be0b810] Opening 'out/720p_002.ts' for writing
[hls @ 0x12be0e790] Opening 'out/1080p_002.ts' for writing
[hls @ 0x12be06030] Opening 'out/360p_003.ts' for writing
[hls @ 0x12be088d0] Opening 'out/480p_003.ts' for writing
[hls @ 0x12be0b810] Opening 'out/720p_003.ts' for writing
[hls @ 0x12be0e790] Opening 'out/1080p_003.ts' for writing
etc

如您所见，ffmpeg 的输出告诉我它正在打开哪些文件进行写入。当关闭文件以进行写入时，ffmpeg 有什么方法可以输出，或者知道何时以编程方式与这些文件交互是安全的？我专门在 Unix 系统上运行它，所以如果答案涉及一些 unix 技巧来监视正在运行的 ffmpeg 进程，那很好，但我宁愿 ffmpeg 在完成写入文件时直接告诉我。

我想:map从 vim cli 将输出写入标准输出，这样我就可以从脚本中读取我的 vim 键盘映射并用它们做一些事情。我怎样才能做到这一点？

我试过vim -c map > out.txt和vim -c "map|q" > out.txt作为文本案例，但都不起作用。:map在 vim 中打开一个寻呼机，我想我可能需要一种方法来绕过它。

当我突出显示一行并gq在可视模式下按下时，我通常希望 (neo)vim 以特定长度换行该行；但是，今天 neovim 开始用以下文本覆盖该行：

zsh:1: unknown file attribute: v

这在今天之前没有发生过。gq通常会调用外壳吗？我怎样才能确定什么gq是呼叫以及为什么zsh不喜欢它？