the Setting of chapter button

the setting button, is the setting for current(last) chapter you select.
- so when more than one chapter in the layer, you should select before click me.
the dialog
function for (from top)
- you can upor downthe layer or the chapter
  - when chapter up to upper layer, will change the time to after all the chapters in the upper layer, for example
    - layer0 duration time is 05:00
    - chapterB at layer1 you move up to layer0
    - the chapterB attime will is 05:00, after the all chapters of layer0
  - to split as new layer, you need change the track number to "New", see below.
- or change the track number, for example:
  - join as seconds layer, this only available when other layers with same type are exist, the example:
    - chapterA in layer0(the track numer 0), chapterB in layer1, both are video chapter.
    - export now you will got two video track, the layer1 never work with the layer0.
    - you can select the chapterB, click the "setting" button, in dialog(see above) you can change the track to 0.
    - now you will see the layer1 track number change to + flag, it mean second layer, same the track number as above.
    - as second layer, always work as lower level layer, see known v2Mixer Layer
    - you can never change track 0 to 1, only can change 1 (or more) to 0. this mean only lower level layer can join to upper.
  - split as "New", you can select this to split with new track number if the layer you selected is the second layer.
- copy Marker, this mean copy the markers from the chapter you select to current Edtior target(the left player target by edit button).
- clear Marker, do clear all the markers of chapter you select(may be not Edtior target, just last chapter you click)
- at, is the offset (of the layer/movie) time of the chapter. by, is the start time of the chapter. to, is the end time of the chapter.
  - the format is hours:minutes:seconds.milliseconds
  - atmean the time for chapter start, for example 00:02:00.000
  - bymean the time for media start(offset), for example 00:03:00.000
    - at is the resource when to startup, by is the time of media offset.
    - in this example, the media will seek to 03:00 as start point, then play back for layer 02:00, the to is the time end
    - so you can cut with marker A,B as clips then join to project, or you can set (maker A) time here let resource seek to right time, and use to do control the end(marker B).
  - tomean the time for chapter should be stop, for example 00:30:00.000
    - tocan out of the media(video, audio and subtitle) duration, will turn as loop mode, just click "Yes" this dialog
  - in this example the video resource 02:00 the chapter will output the image for layer, before 02:00 do nothing.
    the first image come from it's media time 03:00, and will end for media time 31:00.
    - atis the final video time 02:00, until tois the final video time 30:00, so chapter duration 28:00
    - because byis 03:00, so the end time 28:00 is media time 31:00
    - final is the media time 03:00 start play back to layer as 02:00,
      end time 31:00 to layer as 30:00
  - time here is exact match, whatever key-frame its of video, or samples packet size of audio.
    - the audio example, packet 1024 bytes per frame, but time check is per sample(not per packet).
      so if the time tois in the 128 bytes will stop in 128 bytes, not after 1024 bytes.
    - so you don't need to care about the codec packet size/key-frame.
improve
- chapterA and chapterB both in the layer0, or in different layers but same track number, they have no difference. for example:
  
  same as
note
- join as seconds layer let you layer many video as one. also very important for synthetic audio, with Effect Channel Map
- the at, by, to is the value you have to input, not a drag and drop operation, which can be imprecise and cause uneven timing.
- the "by"/"to" time always is it's media time, even with Effect Play Speed, only "at" needs to consider the time after the change, but that's not current chapter problem.