Kdenlive/Руководство/меню Проект/Стабилизация
Стабилизация
Этот пункт меню доступен из контекстного меню клипа, находящегося в дереве проекта или в меню Проект, когда клип выделен в дереве проекта.
Эта функция применяет для клипа, алгоритм стабилизации изображения, который может уменьшить дрожание кадра, обусловленное нестабильным положением камеры (например съёмка с рук и т.п.)
Есть два различных методов стабилизации доступны в 'Kdenlive' - vstab и transcode (перекодировать).
Это видео показывает, рядом сравнение методов стабилизации vstab и transcode .
стабилизация ( vstab)
Основано на этой работе.
В этом учебнике показано, как использовать функцию стабилизации - vstab версии:
Настройки "shutter angle" - расказчик говорит что не знает что это такое (1:35) ... Shutter angle - это угол съёмки - максимальный угол на который может быть повернуто изображение, подлежащее стабилизации. См. здесь.
стабилизация (transcode)
На основании этих советов и документов here значение всех опций:
optzoom = use optimal zoom (calculated from transforms). Causes video to zoom until 90% of transformations are hidden. default - checked. Hint: You can further zoom in with the zoom option
accuracy = accuracy of shakiness detection. Should be >=shakiness factor. 1: low (fast processing) 15: high (slow processing) - default 4. Recommended 8
algo (= algorithm used) checked= small measurement fields - default = checked. Unchecked means use brute force algorithm. The brute force algorithm is deprecated.
maxangle = maximum angle to rotate - in radians. default = -1 which means no limit
relative unchecked = absolute transform (don't use this), checked = relative transform. Default is checked.
zoom - Additional zoom during transform. Percentage to zoom > 0 = zoom in, <0 = zoom out. The zoom specified here is additional to the optimum zoom calculated by the program when optzoom is checked. default = 0
shakiness - how shaky is the video. and how quick is the camera? 1: little (fast processing) 10: very strong/quick (slow processing) Default = 4. Note: large values may also reduce the accuracy. This is due to the internals of the movement-detection. Typically you don't need a value greater than 7.
invert - invert the transform. default = unchecked. Inverting the transform is pointless - leave unchecked.
sharpen - sharpen transformed image. amount of sharpening: 0: no sharpening. uses filter unsharp with 5x5 matrix Default = 0.8
stepsize - step size of search process, region around minimum is scanned with 1 pixel resolution- default = 6
show 0= draw nothing, 1 or 2 = show fields and transforms. Use 1 or 2 to preview what the process is going to do. example default = 0. Non-zero values of this parameter are not relevant in the Kdenlive implementation - use zero.
mincontrast below this contrast - the field is discarded. Range 0-1 default =0.3. You may want to used a smaller value for a really low contrast clip.
smoothing Controls the amount of smoothing/stabilization. The larger the value for smoothing the more camera movements are compensated. The resulting clip has a lower change in camera speed.
Technically it is the number of frames for lowpass filtering = smoothing * 2 + 1.
Eg with a with 25 fps clip, a value of 12 for the smoothing factor means we would smooth over one second - 12 frames behind the current frame + the current frame (1) + 12 frames after the current frame. default =10
Demo of the difference here (top:3, bottom: 30)
maxshift maximal number of pixels to translate image. (default = -1 no limit)
crop unchecked = The border of the transformed frames contains the pixels from previous frames. Checked = black background. default = unchecked
Example of the effect of running stabilize - transcode from the original author - Georg Martius
Side by side
Deshaked
Original