[kdenlive] 16.04 UI audio gain curve adjustment and other thoughts

[Karl Kiniger]

Hi,

just a few observations/comments about adjusting keyframeable audio
gain in the time line :

* How to quickly get rid of the adjustment handles (dont know a better
  name) ? Perhaps by dragging up or down out of the track.

* When you put more than one  handle to the same position (can happen by
  accident) then it is difficult to pick it up again. The selection algo
  will pick some circle and you have to move it somewhere else in order to be
  able to select the desired one.

* Gain curves are now dB-linear, however the gain range goes up to 60dB which
  one will almost never use IMHO (amplitude factor of 1000). I think 20dB or
  even less amplification should be enough for any practical purpose which would
  use the available track height more efficiently w.r.t the dB scale.

* From my (amateurish) experience most of the time audio gain will have to be
  adjusted by, say -30dB (old scale: 3%) up to +10dB (about 300%), perhaps
  up to 15 or 20 dB. Gain below -30 dB will be used only when doing fade
  out or fade in - especially with music material. So the "interesting"
  dB range should perhaps be zoomed vertically in the time line to make
  the interesting gain range better visible.

* When adjusting gain for adjacent clips you have to separately adjust
  the gain at the end of the first clip and the gain at the beginning
  of the second clip. There are circumstances where you want to
  adjust those gains individually but there are also be situations
  where you will want to adjust them in parallel.
  (e.g you want to increase/decrease gain on a few adjacent clips by a few dB)

* It would be nice to be able to vertically zoom tracks individually on
  the time line, especially for the purpose of fine adjusting audio gain.

* When working on split video/audio it is sometimes necessary to adjust
  in/out points for video and audio separately. Currently you have to
  ungroup, adjust, re-group with the chance that you move one clip a
  little by accident and lose video/audio sync. If you dont notice
  this immediately and undo then you will have use the clip properties
  windows to get them back to original a/v sync - very cumbersome.

* Please add user interface for creating audio cross-fades. *please*
  There are two kinds of cross fades (in my projects):
  * very short, just to avoid some audible click or to avoid the
    new audio "jumping" in.
  * longer ones which most likely occur at the same time as a
    corresponding video cross-fade.

* It would be nice to quickly see in the time line if the in/out points
  of a clip are at the very beginning and very end or that there
  is some (a few frames duration?) slack space left.

Opinions are very welcome.

Manipulating the audio was the most time-consuming task on our last
travel movies so these thoughts have accumulated over time in my head
and available as written e-mail from now:-)

Nevertheless, I think that Kdenlive is already the most advanced
video editor in open source world and I never considered switching to
commercial products.

In despair one can always write some python script to manipulate the
xml project files like in the situation when I discoverd that my
mpegts 1080p50 files from Pananasonic camera (dont remember exact
model name, something with 900) and discovered frozen video images
(up to almost one second!) in the final render output and had to
re-mux to h264/pcm_16le in mov container. then I transformed the project
file with python script to use the new file names andproperties.

Suddenly no more problems and at the same time usable timeline
display without using proxy clips on quad core i5 processor +
some medium level nvidia card.

Congrats to all who read that far, :-)

Best regards,
Karl