Showstopper: timeline playhead positioning delays. Is it a bug? Anything user can do?

[DogFilm]

I am using MP4 files, however the described delay is unique to Kdenlive
(compare to several different video editing softwares on the same hardware).

On Mon, Sep 23, 2019 at 1:24 PM Alistair Riddoch <alriddoch at googlemail.com>
wrote:

> I am not a developer, but I am interested in better understanding your
> issues.
>
> On Mon, Sep 23, 2019 at 12:10 PM DogFilm <videobrain at gmail.com> wrote:
>
>> Many editors do lots of manual micro-movement in the timeline to find
>> good cut points, what seems to be possible with Kdenlive using [shift |
>> alt] left / right arrows to position the playhead.
>>
>> The playhead unfortunately always has some significant delay in following
>> these keyboard movements, what adds up to the level of "not usable in real
>> life" for "real" editing.
>>
>> One [shift] left action takes between one and two seconds, moving right
>> seems to be a bit quicker, but still far away from the expected immediate
>> positioning. What makes it worse: it adds up. So if you press seven times
>> left arrow because you want to position exactly seven frames before the
>> actual playhead position, it takes even longer. Looks like some positioning
>> calculation could be optimized.
>>
>
> Seeking left in kdenlive can be very dependent on the video file format
> being used. For example with AVCHD files (which are fairly well known to be
> poorly suited to editing) stepping left works very poorly, but with
> Matroska Video or MP4 files it works much more fluidly.
>
> What format of video files are you using?
>
>
>>
>> This is especially annoying when positioning while the timeline is
>> playing - this must of course be possible without any perceived delay.
>>
>> I understand that the timeline code is new, however this delay is a show
>> stopper. If I show this to friends with many years of experience in editing
>> they will just look at me with a big question mark ini their eyes -
>> "seriously???"...
>>
>> To understand how this feels to someone editing videos every day, imagine
>> your text editor would delay every cursor movement, you can then understand
>> which level of "not acceptable" this is.
>>
>> Is this is bug?
>> Can the user do anything to enhance that timeline positioning?
>>
>> This is an extremely basic thing and very important to get it right.
>> Timeline positioning of course must work or at least feel like an
>> immediate action.
>>
>> I guess it feels somehow strange to explain this to programmers of a
>> video editing app, but I came to the conclusion that you may not have that
>> on top of your testing list, otherwise the app would not have been released
>> with that basic problem, so somebody needs to make you aware of that
>> elephant-in-the-room that you do not seem to be relevant - it is very much!
>>
>> Thanks again!
>>
>>
>>
>
> --
> Alistair Riddoch
> alriddoch at googlemail.com
> http://alistairriddoch.org/
>
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