The compensation of movements in an image results in borders.
For instance, when an image is repositioned 10 pixels to the left to compensate for camera shake to the right, a border or rather a gap in the data will appear on the right of the image. This will generally be shown as no content, or a black image area. In this section of the Mercalli dialog, you can decide how to deal with the border data, so you can optimise the stabilised video footage for further use.
Without border (upscaled)
With this setting selected, Mercalli will first stabilise the image and then upscale it as much as is required by all the stabilisation movements and the resulting borders, to generally avoid the border effect.
Advantage: the border is still, without any movement.
Disadvantage: depending on the level of stabilisation, you may have to upscale the image a lot, which will result in a loss of focus.
With this setting selected, Mercalli will create a static border around the image. The border width is as large as required by all the stabilisation movements to avoid a flickering border.
Advantage: very still border, no scaling (you can add scaling later in your video editing program)
Disadvantage: if a lot of movement has to be compensated, the border may be quite wide.
With this setting selected, Mercalli adapts the border for each frame of a video sequence.
Advantage: the border can be generally less wide, only strong movement compensation will require wider borders.
Disadvantage: the border may appear to flicker, particularly with more intense stabilisation.
Level of scaling
Use the slider control to set a level of scaling for a
- “static border”
- “dynamic border”
This lets you slightly reduce the border effect (optional).
Fill up border area
With this checkbox selected, the black borders are coloured in.
The colour used depends on the image content of the original video signal. To reduce strong image noise in the border area, the image is blurred towards the video border area.
You should select this option whenever the pixels closest to the border area have a relatively uniform colouring, such as in footage of water or the sky (e.g. when filming animals in water or planes in the sky; these would generally be in the centre of an image).