In a compositing, it is frequent to remove unwanted camera movement such as jitter, roll, zoom or pan.
This exercise shows how to stabilize a shot using the Auto-Stabilizer tool.
Tools used in this exercise: Batch, Auto-Stabilizer.
Exercise: Auto-Stabilizing a shot.
Click on the icon for a quick preview of the exercise and the final result.
Video: FF_The_Castle
(click on image to open video player)
Download an archive that contains the footage as well as the setups used in this exercise.
Put these files in your Flame system: for example under the /usr/tmp directory.
To learn how to load material into the Flame Library, see the exercise:
“Loading an archive”
Footage courtesy of: Hybride, a Ubisoft division
Images are subject to copyrights: please read the Disclaimer at the end of the tutorials.
In this example, the camera is rolling on a bumpy cobble stone pathway. We need to neutralize the jitter while keeping the camera move. To achieve this we can use an Auto-Stabilizer node in Batch to stabilize the shot. Afterward the stabilized shot can be used with another Batch node.
Start in Batch.
1. Change the setup duration to 20 frames.
2. Be sure Auto Key is OFF.
3. Click and drag the Library node to the Batch schematic.
4. In the Library, select the clip “Petit_Trianon”.
5. Press Load.
6. Drag an Auto-Stabilizer node to the Batch schematic.
7. Connect the clip to the node.
8. Select the Auto-Stabilizer node and press F4 to result view.
Video: Castle_v01
(click on image to open video player)
Start by analyzing the shot and subsequently you can refine the result and modify the stabilizing settings.
In this example we track the entire frame but you could define a region of interest to analyze a smaller area of the image.
1. Verify that the Range goes from 1 to 20 frames.
2. Keep the default settings and press Analyze.
The analysis is done on the front clip.
Castle_image1
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To define a region of interest to be analyzed you need to be in front view. Enable ROI, deactivate Auto draw a selection box.
The analysis process generates trackers that are displayed as a cloud of green track points. You can improve the tracking several ways: using a matte connected to the matte tab, modifying the scene flexibility (tolerance factor), defining a ROI, using different parameters and deleting bad trackers.
1. Switch to Result view, press F4.
2. Play the clip and look at the result so far.
3. Identify poor trackers that are shaky or don’t stay there long enough.
4. Select these trackers, they turn red, and press Delete & Update.
5. Scroll the clip again to see the result.
6. In this case, we don’t need to stabilize the horizontal movement:
Deactivate the Position X Stabilization.
But Keep Position Y and Rotation.
Video: Castle_v02
(click on image to open video player)
Use the 2D Transform Offsets controls to reposition the final image.
These settings can be animated over time if needed.
1. Work in Result view, press F4.
2. Scroll to a frame where size and position adjustments are necessary.
3. Scale the image and adjust the position to your liking.
Note: Perspective Offsets controls are used for Perspective Type Analysis, which is not the case here.
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You can choose padding, Anti-Aliasing and Resize options directly in the Auto-Stabilizer node.
Depending on how much the shot is scaled up, you may improve the Anti-Aliasing options.
Video: Castle_v03
(click on image to open video player)
When you are satisfied with the result, you can render the final clip with an Output node, or connect it to another Batch node.
Castle_image2