Implemented 'on disk editing'

MANUAL

@@ -174,6 +174,52 @@ Video Disk Recorder User's Manual
             used to easily delete a recording after watching it, or to switch
             to a different recording.
 
+* Editing a Recording
+
+  While in Replay mode, the following keys can be used to manipulate editing
+  marks:
+
+  - 0       Toggles an editing mark. If the mark indicator shows a red triangle,
+            the current mark is deleted. Otherwise a new mark is set at the
+            current position.
+  - 4, 6    Move an editing mark back and forward. You need to first jump to
+            an editing mark for this to work.
+  - 7, 9    Jump back and forward between editing marks. Replay goes into still
+            mode after jumping to a mark.
+  - 8       Positions replay at a point 3 seconds before the current or next
+            "start" mark and starts replay.
+  - 2       Start the actual cutting process.
+
+  Editing marks are represented by black, vertical lines in the progress display.
+  A small black triangle at the top of the mark means that this is a "start"
+  mark, and a triangle at the bottom means that this is an "end" mark.
+  The cutting process will save all video data between "start" and "end" marks
+  into a new file (the original recording remains untouched). The new file will
+  have the same name as the original recording, preceeded with a '%' character
+  (imagine the '%' somehow looking like a pair of scissors ;-). Red bars in the
+  progress display indicate which video sequences will be saved by the cutting
+  process.
+
+  The video sequences to be saved by the cutting process are determined by an
+  "even/odd" algorithm. This means that every odd numbered editing mark (i.e.
+  1, 3, 5,...) represents a "start" mark, while every even numbered mark (2, 4,
+  6,...) is an "end" mark. Inserting or toggling a mark on or off automatically
+  adjusts the sequence to the right side of that mark.
+
+  Use the keys described under "Replay Control" to position to, e.g., the
+  beginning and end of commercial breaks and press the '0' key to set the
+  necessary editing marks. After that you may want to use the '7' and '9'
+  keys to jump to each mark and maybe use the '4' and '6' keys to fine tune
+  them. Once all marks are in place, press '2' to start the actual cutting
+  process, which will run as a background process. When replaying the edited
+  version of the recording you can use the '8' key to jump to a point just
+  before the next cut and have a look at the resulting sequence.
+
+  Currently editing marks can only be set at I-frames, which typically is
+  every 12th frame. So editing can be done with a resolution of roughly half
+  a second. A "start" mark marks the first frame of a resulting video
+  sequence, and an "end" mark marks the last frame of that sequence.
+
 * Programming the Timer
 
   Use the "Timer" menu to maintain your list of timer controlled recordings.