Stabilize Module
Table of Contents
Note: This section only relates to mocha Pro. This feature is not available in mocha AE. For a full comparison of features, please refer to the comparison chart online.
The stabilize feature in uses the data you have tracked to lock down a moving shot. You can think of it as the inverse of what tracking does: It moves the footage around an area rather than an area around the footage. Stabilization is useful for:
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Removing camera jitter and bumps
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Locking off a shot so it is easier to work with, before restoring the motion back into the final composition
Stabilization is a fairly straightforward operation. Once you have selected the tracked layer you wish to work with you have options to restrict the stabilization to key details.
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Input Tab
Select the clip that you wish to use to stabilize here.
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Range Tab
Select the frame range for the stabilization.
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Fixed Frames
Here you can enter the frames you want to be unaffected by stabilization. Mocha will adjust the stabilization between these frames. You can either enter them into the field, or go to a frame and press the + key.
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Fixed frames can be useful when you want stabilization across a shot but would like to keep the general motion of the original shot intact.
Smooth
This is the main section for controlling how you want the shot to stabilize.
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All Motion
This checkbox sets all the options below it.
X Translation
Stabilize translation in X
Y Translation
Stabilize translation in Y
Rotation
Stabilize rotation
Zoom
Stabilize the scale/zoom
X Shear
Distort the footage according to the tracked surface’s shear data in X
Y Shear
Distort the footage according to the tracked surface’s shear data in Y
X Perspective
Distort the footage according to the tracked surface’s perspective data in X
Y Perspective
Distort the footage according to the tracked surface’s perspective data in Y
Shear and Perspective stabilization can be useful when you want to straighten out a plane in your footage to work on it flat before restoring it to its original perspective and motion.
Maximum Smoothing
Stabilize across the entire track. Setting this value will override the #Frames value beneath it.
# Frames
Stabilize variation across a certain amount of frames. Setting this to a low value will focus the stabilization to only pick up motion that occurs in short bursts (such as a bump in the road). A higher value will try to adjust longer movements.
This tool helps automate removing the black edges you gain from the footage being stabilise.
Centre
This centres the footage around the stabilised area.
Zoom
This zooms into the footage to push the edges out of frame.
Crop
This crops down the edges and makes the footage smaller.
You can use Auto Fill to help fill in the black edges with previously tracked layers, similar to how mocha’s remove tool uses tracked background layers to remove foreground objects. If you have sufficient usable background available, you can avoid reducing the quality or resolution of footage, which is a common problem in stabilisation.
For a better understanding of background fills, please refer to the Remove documentation.
Auto Fill
This turns on the auto fill function. You will not see the effect of fill however until you render the result.
Search Range
The range of frames to look for possible fill frames.
Model Illumination
Like the Illumination modelling in the remove tool, this tries to calculate the correct lighting for a filled-in edge.
Dissolve
This gives the option of dissolving the edge of frame into the filled frame to reduce obvious mismatches.
Fill from Background
If you haven’t set up a tracked background layer to use to help fill the edges, you can let mocha attempt to fill by analysing the footage. This is mostly useful for filling in frames where there is only position and rotation jitter.
One of the most common reasons to stabilise is to remove jitter from a shaky camera shot. With shaky camera footage you are primarily concerned with removing position and rotation data. This means you do not have to use the shear or perspective options when tracking. Here is the common method:
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Track a static area of the shot using Translation, Scale and Rotation only. You don’t want to track a moving object within the shot as this will throw off the stabilisation.
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Once tracked, switch to the Stabilization tool.
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Choose which fields of motion you wish to stabilise in the Smooth parameters. By default, translation is automatically selected. In many cases you may only be interested in position stabilisation, but hand-held cameras can introduce scale and rotation jitter as well.
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Adjust the number of frames you want to look for jitter over. A small amount of frames will look for tiny adjustments in the overall motion, whereas bigger values in this field will adjust larger ranges of motion.
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If there is a significant amount of motion being stabilised and you are losing a lot of your picture in some frames, try fixing those frames by adding them to the Frame List on the left. Mocha will then interpolate the stabilisation between these fixed frames.
Sometimes you want to be able to completely lock down a section of the footage so that it stays in one place and everything else moves around it. For this you can use more aggressive stabilisation:
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Track the area you want to lock down using whichever of the motion paramters you require. Tracking perspective also works for this technique.
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Once tracked, switch to the Stabilization tool.
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Choose which fields of motion you wish to lock down in the Smooth parameters. By default, translation is automatically selected. If you want to completely lock down everything, just choose the “All Motion” checkbox.
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Adjust the number of frames you want to use to look for stabilization. A small amount of frames will look for tiny adjustments in the overall motion, whereas bigger values in this field will adjust larger ranges of motion. Again, if you want to completely lock down everything for all motion, choose the “Maximum Smoothing” option.
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When you play back the timeline you will see the rest of the footage warp and move around your locked off area.
