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--- c3tracker:cutting [2026/03/25 16:28] – andi
+++ c3tracker:cutting [2026/07/26 22:17] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
-= Tracker Cutting Howto
+# Tracker Cutting Howto
 When we talk about "cutting a video", we mean a highly automated process how the intro and outro get added to a recorded lecture using the [[c3tracker:start|]].
@@ Line 9: / Line 9: @@
-== Cutting with FUSE
+## Cutting with FUSE
 There are two main ways of cutting a video: Using the KDEnlive or Shotcut open source video editors or by manually writing frame numbers to obtained from a video player like mpv the in- and outframe files.
@@ Line 20: / Line 20: @@
   * Have VLC installed
   * On Linux: Install ''cifs-utils'' (or similar) to mount the SMB share
-  * On Linux: Install KDEnlive (versino 17.x or 18.x) or Shotcut (version 22.12.21 is known to work)
+  * On Linux: Install Shotcut (version 22.12.21 is known to work) or KDEnlive (version 17.x or 18.x)
   * On Windows/ macOS: Install Shotcut as described at [[https://shotcut.org/download/|their website]] (Version 22.12.21 is known to work)
-=== General Workflow
+### General Workflow
 <bootnote>The following commands will use //storage.lan.c3voc.de// as a placeholder for the machine with the FUSE mounts. Small events may use //encoderX.lan.c3voc.de// or //minionX.lan.c3voc.de// as storage share.</bootnote>
@@ Line 55: / Line 55: @@
     * click "finish"
-=== Notes on Using KDEnlive
+### Notes on Using KDEnlive
 Open the ''project.kdenlive'' project file to start cutting:
@@ Line 65: / Line 65: @@
 If you have a poor connection to the storage, deactivate the video and audio thumbnails using the buttons on the right side of the lower window border.
-=== Notes on Using Shotcut
+### Notes on Using Shotcut
 Open the ''project_shotcut.mlt'' project file to start cutting:
@@ Line 87: / Line 87: @@
     * <code>apt-get install libQt5Gui</code> (see http://stackoverflow.com/questions/17106315/failed-to-load-platform-plugin-xcb-while-launching-qt5-app-on-linux-without)
-=== Notes on Using mpv
+### Notes on Using mpv
-If you like the command line, you can also configure mpv to show frame numbers by adding these settings in ''~/.config/mpv/mpv.conf'':
+''mpv'' is a command line media player, which can also be used in our cutting workflow.  [[user:nicoo]] wrote [[https://forgejo.c3voc.de/voc/mpv-scripts|an mpv script]] which automates our cutting workflow.
+See [[https://mpv.io/manual/master/#keyboard-control|the ''mpv'' manual]] for the default keybinds.
+#### Setup
+Install the script, typically by copying ''c3voc-cutter.lua'' to ''~/.config/mpv/scripts/''.  If using a mountpoint other than ''/video'', it needs to be set in ''~/.config/mpv/script-opts/c3voc.conf''.
+The script does not add keybindings by default, and those must be configured in ''~/.config/mpv/input.conf'' like so:
+<code>
+% script-binding c3voc-cutter-jump-in
+^ script-binding c3voc-cutter-jump-out
+Ctrl+5 script-binding c3voc-cutter-set-in
+Ctrl+6 script-binding c3voc-cutter-set-out
+</code>
+mpv can also be configured to show frame numbers by adding these settings in ''~/.config/mpv/mpv.conf'':
 <code>
 osd-level=3
 osd-status-msg=${playback-time/full} / ${duration} (${percent-pos}%)\nframe: ${estimated-frame-number} / ${estimated-frame-count}
 </code>
+If using nix / home-manager, the script repository is a flake providing the necessary configuration as NixOS and HM modules; just add the following to your (NixOS) imports, replacing ''nicoo'' with your local username:
+<code>
+{
+  imports = [ c3voc-scripts.nixosModules.default ];
+  home-manager.users.nicoo.imports = [ c3voc-scripts.homeModules.default ];
+  c3voc.user = "nicoo";
+}
+</code>
+#### Usage (with script)
+* Open ''uncut.ts'' in mpv to start cutting
+* Skim through the video to find the start
+  * mark it by hitting ''Ctrl+5'' (or whichever keybind you set)
+  * jump back to it with ''Shift+5''
+  * you can hit ''Ctrl+5'' again at any point to set a new startpoint
+* Same for the end
+* ''mpv'' will write the ''inframe'' and ''outframe'' file when exiting or switching to a new file.
+#### Usage (manual)
 Open the ''uncut.ts'' in mpv to start cutting:
@@ Line 100: / Line 137: @@
   * Do the same for the end using the ''outframe'' file
-Using "echo" works best since some text editors like to create temporary lock files which isn't allowed on the FUSE file system.
+Using ''echo'' works best since some text editors like to create temporary lock files which isn't allowed on the FUSE file system.
-Additional keyboard shortcuts: See https://mpv.io/manual/master/#keyboard-control
+#### Tips
+  * [[https://github.com/po5/thumbfast|thumbfast]] can generate thumbnails live, for instance when hovering over a seek bar, which can help find the start and end of a talk faster. (Note: it needs to be used with a UI script, and supports most MPV UIs)
+  * [[https://github.com/po5/evafast|evafast]] gives fast-forward and seeking on the same key, which is rather convenient.
+  * [[https://github.com/CounterPillow/mpv-quack|quack]] reduces the volume when seeking, to avoid torturing one's ears during cutting
+For nix users: those are all packaged, and can be added with
+<code>
+programs.mpv.scripts = with pkgs.mpvScripts; [
+  evafast
+  quack
+  thumbfast # NOTE: useless on its own, combine with its builtin osc.lua, or with alt. OSCs like uosc
+];
+</code>
-== Known Issues and Solutions
+## Known Issues and Solutions
   * Shotcut or VLC don't show a time during playback:
@@ Line 115: / Line 166: @@
-== Remote Cutting using a Proxy File
+## Remote Cutting using a Proxy File
 The ''uncut.ts'' can get quite large as we're still recording using the MPEG2 codec.